I just bought a lenovo ideapad and installed 14.04lts. Currently it shows the wi-fi icon as trying to connect but a few second later it shows the alert that I have been disconnected. Can anyone help? Is there any set of drivers or other software that I need to install?  My current wireless card is: Realtek Semiconductor CO.,ltd RTL8723BE PCIe wireless Network Adapter

I have installed Ubuntu 15.04 on my laptop with RTL8723BE Wi-fi card. But it is always disconnecting from network. I have tried echo "options rtl8723be fwlps=N ips=N" | sudo tee /etc/modprobe.d/rtl8723be.conf but that didn't helped. What can I do to prevent the wifi from disconnecting? If I upgrade to kernel 4.X, will it help?  ~$ lspci -knn | grep Net -A2  09:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter [10ec:b723]     Subsystem: Hewlett-Packard Company Device [103c:2231]     Kernel driver in use: rtl8723be   ~$ rfkill list 0: hci0: Bluetooth     Soft blocked: yes     Hard blocked: no 1: phy0: Wireless LAN     Soft blocked: no     Hard blocked: no   ~$ ifconfig && iwconfig && route -n && ping -c 1 google.com eth0      Link encap:Ethernet  HWaddr 38:63:bb:cd:4a:7e             UP BROADCAST MULTICAST  MTU:1500  Metric:1           RX packets:3 errors:0 dropped:0 overruns:0 frame:0           TX packets:53 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:752 (752.0 B)  TX bytes:8445 (8.4 KB)  lo        Link encap:Local Loopback             inet addr:127.0.0.1  Mask:255.0.0.0           inet6 addr: ::1/128 Scope:Host           UP LOOPBACK RUNNING  MTU:65536  Metric:1           RX packets:3870 errors:0 dropped:0 overruns:0 frame:0           TX packets:3870 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:0            RX bytes:314613 (314.6 KB)  TX bytes:314613 (314.6 KB)  wlan0     Link encap:Ethernet  HWaddr c0:38:96:6d:c4:83             inet addr:192.168.1.205  Bcast:192.168.1.255  Mask:255.255.255.0           inet6 addr: fe80::c238:96ff:fe6d:c483/64 Scope:Link           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1           RX packets:15240 errors:0 dropped:0 overruns:0 frame:0           TX packets:14627 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:14410285 (14.4 MB)  TX bytes:2192744 (2.1 MB)  eth0      no wireless extensions.  wlan0     IEEE 802.11bgn  ESSID:"DIR-615"             Mode:Managed  Frequency:2.437 GHz  Access Point: 00:90:4C:08:00:0D              Bit Rate=150 Mb/s   Tx-Power=20 dBm              Retry short limit:7   RTS thr=2347 B   Fragment thr:off           Power Management:off           Link Quality=70/70  Signal level=-22 dBm             Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0           Tx excessive retries:0  Invalid misc:186   Missed beacon:0  lo        no wireless extensions.  Kernel IP routing table Destination     Gateway         Genmask         Flags Metric Ref    Use Iface 0.0.0.0         192.168.1.1     0.0.0.0         UG    400    0        0 wlan0 169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 wlan0 192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 wlan0 PING google.com.Dlink (172.26.136.19) 56(84) bytes of data. 64 bytes from 19.136.26.172.in-addr.arpa (172.26.136.19): icmp_seq=1 ttl=249 time=102 ms  --- google.com.Dlink ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 102.547/102.547/102.547/0.000 ms


when running Software Updater from my Ubuntu 14.04 Desktop install, I get the following errors:  W:Failed to fetch http://archive.ubuntu.com/ubuntu/dists/$(lsb_release/-sc)/binary-i386/Packages  404  Not Found [IP: 91.189.88.153 80],  W:Failed to fetch http://archive.ubuntu.com/ubuntu/dists/$(lsb_release/universe/binary-i386/Packages  404  Not Found [IP: 91.189.88.153 80], W:Failed to fetch http://it.archive.ubuntu.com/ubuntu/dists/trusty-updates/main/binary-i386/Packages  Hash Sum mismatch,  W:Failed to fetch http://it.archive.ubuntu.com/ubuntu/dists/trusty-updates/universe/binary-i386/Packages  Hash Sum mismatch   How may I fix this? Thank you. Regards

There are now errors when updating and I cannot install most software due to a corrupted  /etc/apt/sources.list   file. Is there a copy I can download to replace it?  The file would be for Ubuntu 12.04 (Final Beta) in the United States.


I really wanted to try out something different then Windows 7. So I installed Ubuntu and I have no clue on how to work it. I’m totally lost and have been trying to go back to windows by using the windows disc I made my recovery of, and its not working like Im trying. I have a Toshiba Satellite L655-S5096 windows 7 64 bit.  I have been trying to run different disc also like the rescue cd,dban 2.2.8, Dariks Boot and Nuke, to name a few..I guess Im so use to windows commands and cant get a grip on how to delete this so I can do a clean install of my Windows 7.   Could anyone please help walk me through deleting Ubuntu and installing windows back on here.

I have absolutely no experience with Linux, and I desperately need to get my computer back up and running again with Windows.  How do I remove Ubuntu and reinstall Windows?    Editor's note: many of the answers are about removing Ubuntu from dual-boot but keeping Windows (which is a bit complicated), while other answers are about removing Ubuntu from single-boot (which is easy: basically just format the disk while installing Windows). The question as written is ambiguous between dual-boot or single-boot.


I am dual booting Ubuntu 19.10 and windows 10 and I keep getting notifications that my / directory has low space. The size of / is 8GB. I have run sudo apt clean but it did not free up much space.  I have been trying to understand if I need to extend that partition and some guides I have found have not helped me. Is there no easy way to just add to it from the free disk space I have? Or do I have to create a new root partition and move everything there?  Any help appreciated.

Previously, I have installed Windows 7 on my 320 GB laptop with three partitions 173, 84 and 63 GB each. The 63 GB partition was where the Windows was installed. The rest were for file containers.  Now I changed my OS to Ubuntu 12.04 LTS. I installed Ubuntu by replacing the entire Windows 7 on the 63 GB partition. The rest of the partitions remain as an NTFS Windows partition and I can still access them both (the 173 and 84 GB partitions).  Now I want to change the two partitions of Windows into an Ubuntu format partitions plus most importantly, I want to extend the 63 GB partition to more than a 100 GB because at the moment I am running out of disk space. Whenever I try to install any application, especially using wine, it always complains for a shortage of disk space.  How do I do the extending activity before I entirely format my laptop again and lose all the important files on my partitions?


Hopefully just a quick one, I can see various answers to my problem but finding it difficult to implement into my code. As the title says, looking to allow apostrophes when posting data to MySQL using ajax and javascript. When submitting data just now, it doesn't work.   Hoping someone can finalise the code to make this work.   HTML

             <button type="button" class="close" data-dismiss="modal" aria-label="Close">&times;</button>
Add some useful information

                 Add Info                 <input type="text" id="info" class="form-control"/>

             <button type="button" class="btn btn-default" data-dismiss="modal">Cancel</button>             <button type="button" class="btn btn-primary" onclick="addRecord()">Add Record</button>

    Javascript  // Add Record function addRecord() {     // get values     var info = $("#info").val();      // Add record     $.post("ajax/addRecord.php", {         info: info     }, function (data, status) {         // close the popup         $("#add_new_record_modal").modal("hide");          // read records again         readRecords();          // clear fields from the popup         $("#info").val("");     }); }   Ajax - addRecord.php  <?php     if(isset($_POST['info']))     {             // include Database connection file             include("db_connection.php");              // get values             $info = $_POST['info'];              $query = "INSERT INTO useful_info(info) VALUES('$info')";             if (!$result = mysql_query($query)) {             exit(mysql_error());         }         echo "1 Record Added!";     } ?>   From reading other questions on the site, I can either use get_magic_quotes_gpc or by creating a JSON object and use JSON.stringify. Just wondering how best to achieve this.  Any help would be appreciated.

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


Since the Social Media is pivotal to building and maintaining interpersonal relationships - hence, central to human existence - it becomes imperative to investigate the current trend in language use on this principal communication media.   I want to know if this sentence is grammatical and unambiguous. Thank you.

I have noticed that some native english speakers use the "-" sign to explain some additional things in a sentence: eg     Sophie is going to the shop - which happened to be around the corner -   to buy some groceries.   Before knowing this notation I would write the same sentence as follows:     Sophie is going to the shop, which happened to be around the corner,    to buy some groceries.   To me the "-"-sign seems much  clearer than a comma. Am I using the "-" correctly. If so what is the difference between a "," and a "-".


I know what a reverse transcriptase is but I'm not sure why it is suggesting that the central dogma may be wrong -- RNA first then DNA instead of the well-known sequence of DNA -> RNA -> protein

I was recently reading about non-coding RNAs being a counter example to Central Dogma of Biology. Can someone add more cases which violate the Central Dogma? Thanks!  UPDATE - Reference of lncRNAs violating Central Dogma:     Although the central dogma remains a core tenet of cellular and     molecular biology, the appreciation of lncRNAs as functional genomic     elements that defy the central dogma may be essential for fully under-    standing biology and disease. []


I've built a project with several shapefiles and Google Satellite as a background. Everything seems to be perfectly fine, I manage to prepare the Print Layout but when I finally save as image or PDF, the Google Satellite imagery becomes misaligned with the shapefiles.  I've tried reprojecting all SHPs to EPSG 3857, with no change in the final result. How can I solve this?

I'm having trouble with the OpenLayers Plugin of Qgis and the map composer:  If I create an OSM-background layer and if I want to export this, the OSM-Layer looks perfectly all right in the normal qgis program window. But in the map composer and after export the layer has shifted relatively to my other shape layers (EPSG:32633 - WGS 84 / UTM zone 33N).  The second thing is that the output resolution of the exported osm-layer is very, very poor.   A really bad way of getting around this whole trouble would be to increase the screen resolution and make a screenshot of the map composition window of qgis. But I don't think this would be very professional. It also would cause a lot of pain :)   I'm using Qgis 1.8.0-Lisboa under Linux. The openlayers plugin is version 0.92.


So, I'm on my friends Realm and we're trying to make a Nether hub, which we did in a previous Realm about a year ago (hers expired and didn't get a new one). She built up a portal that's 5 across, and 6 up and lighted it. She jumped through and then came back, so she could start getting coordinates of my portal so she could make one in the Nether that would make you go directly from there to my portal in the Overworld. Now, here's the problem: She came out of the portal, and ended up in a new place. I went through my own portal, then back, and ended up coming out of the same portal she went through coming back. She had to go, so I destroyed the portal that we kept coming out of. Then, I went through the big portal she made and then back, and it spawned another portal again. Both portals are close to the big portal she made, but we're still confused on why it keeps spawning new portals and not letting us come back through the one we already made.

On our minecraft server, I've built a Nether portal in my basement. Which connected two-way (tested) to a location in the Nether.    This nether portal took me to an area in the nether which was a small cave. I dug upwards and surfaced close to a Nether Fortress. After clearing the fortress of Blaze spawners, I decided to 'move in'. So I went back to the portal, dismantled it, and reactivated in in a location in the Fortress.    The fortress would be within the same 128m radius I would assume as it's really close to the original place. Literally some steps to the surface, then a ladder up the nearest Nether Fortress bridge support.  Now, taking this portal back to my original doesn't work, I spawn deep underground in an Abandoned Mine Shaft.  I read somewhere that my Nether portal has found a 'better match' and this could be remedied by disabling the 'wrong' portal in the mine shaft.  However, upon multiple attempts, a new nether portal is dynamically created in the same area. See screenie for example. You'll see two 'stacked' portals on the left (from my different attempts at disabling) and then the current active one on the right.    My question is, how can I make sure these portals go to the correct place. Is it a matter of returning the portal to it's original location or am I stuck for returning to the basement?


I face the problem of writing a good question in Stack-overflow sites.  What is the best way to write a good question?

The title of  of  is, "Is it posible [sic]?"  This doesn't provide any information at all. It should be mandatory for everyone asking questions on the Internet to read , which says:     Help your community learn from the question. When you field a good question, ask yourself "How would the relevant documentation or FAQ have to change so that nobody has to answer this again?"


In 1940 there were $245,300$ immigrants admitted to a country. In 2006 there were $1,060,431$. Write a linear equation expressing the number of immigrants, $y$, in terms of $t$, the number of years after 1900. What is the estimate of immigrants in 2015?

Find the equation of the line that passes through the points $(2, 9)$ and $(8, 6)$. Write the equation in standard form.


I always used to think that monthly mortgage payments had fixed proportion of interest payments and house payments (determined by rate and term). But, I recently heard that you start off with making most of your payments on interest and slowly more of it becomes house payment.   Why is this so? Is it to force people to stick to their mortgage? And, is there a method to calculate the proportions over time?  Any help would be appreciated. Thanks!

When you take out a traditional mortgage the first payment you make to a bank pays off mostly interest and then later payments start paying off principal.   What is the reason for this?   Is it just a historical accounting/industry convention? Or is there some reason why it happens this way?


What do I say for somebody keeps bringing up and talking into somebody's ear about the same topic again and again till he is fed up and finally agrees to it?   Example: Mary's been [word or idiom] to John till he finally bought it for her.

What is the word for act of "demanding for something (many be a toy) repeatedly along with a monotonous sound (not very loudly and not crying)"?  I guess 'whine', 'whimper', or, 'solicit' would not be applicable.  Is that 'nagging'?


How would one make a symbol, say \circ in a symbol separated set of letters i.e. A_{\circ} B appear at the top between the letters i.e. A^{\circ} B, but to an arbitrary height (not just using _ or ^)?  Thanks.

I have a small nitpicking query  I have:  $S\sqsubset\mathbf{P}$   and noticed that the \sqsubset symbol is a bit too low (off centered) for my liking. Is it possible to shift it up slightly?


So I'm currently working on applying for my UK Tier 5 Youth Moblility Visa. I am a 21 year old from Canada.  I am worried that a past experience in the UK will be a problem, let me explain.  A few months ago I was backpacking across Europe and spent a lot of time in the UK as I lived with some friends there. I was only there under the ordinary 6 month tourist visa. I stayed for around three months and then went back to Canada. Then around three weeks later went back to pass through Gatwick Airport to Stansted Airport to catch a flight to Norway. The woman was a bit suspicious that I was back so soon but I explained I had a flight to Oslo in two days.  Then around a month and a half later, I came back to the UK for the birthday of my friend and her son. Their birthdays are close together. Frankly, when I got there UK immigration was very suspicious because I was back for a third time and soon. Also, as I backpack and hitchhike a lot, couchsurf and do all I can to save money, I have little funds and they were suspicious about that as well.  They detained me, took my fingerprints and interviewed me under recording.  After a few hours, they phoned my friend and then decided I was ok to be let into the UK. They then let me into the UK but put a special stamp in my passport. From what I understand, the stamp signifies that I need to be asked additional questions.  I stayed for around two months as we all made plans to go to Portugal together which I didn't expect. Then we did and later I went to Ireland by myself.  During my time in the UK, my friend paid for my food and let me stay at her place. I got funds from my parents but not through my own bank account. (should I mention this on my application?)  So I was not refused entry, so I've already decided that I don't need to say that I've ever been refused entry into the UK on my application.  But they will be taking my fingerprints when I send the application to the visa center in my city. So I will probably show up on their records. I don't want them to look at me in any bad way whatsoever. I loved the UK and I very much want to live there for two years. Will this hurt my chances?  Should I mention this incident on my application so it doesn't seem like I'm trying to hide it?  I'm thinking if I don't mention it, when they're processing my application and do research they might see me show up on the system and automatically deny me because they're assuming I'm not trustworthy.  Also, will my history in the UK as a tourist and not spending money be suspicious? How can I counteract this? I will have enough money in my bank account to apply but during my time in the UK this bank account was mostly empty as I got help from my parents. I spent very very little money anyways. Around 100 pounds per month.  I could really use support on this. Thank you.

I am a Canadian applying for a UK Tier 5 Youth Mobility Visa.  At one point during the application process, it asks if I have ever been denied entry into the UK, but I am not sure what to answer with.  A few months ago I was returning to the UK again after visiting it recently on a tourist visa. I was coming for the birthday of my friend and her son (their birthdays are close together).  Immigration was wondering why I was back again so soon and were a bit suspicious about my funds so they detained me for around 3-4 hours. They took my fingerprints and interviewed me. Afterwards they phoned my friend and after talking to her on the phone (she explained everything) they let me go through and enter the UK.  So in the end, they let me enter the UK.  So was I technically refused entry? Should I say that I was refused entry on my application? I'm afraid that it looks bad and might automatically get me denied, even though I was let through in the end.


Hestu, as in the guy you give Korok seeds to. After I first met him and completed his quest, he's no longer in that same spot. Where can I find him?

In Zelda: Breath of the Wild, where in Hyrule can I hand in my Korok Seeds to gain rewards?


I have the following:  <iframe src="ACRBusinessCL.pdf" id="PDFtoPrint" height="800" width="800"> </iframe> <form> <input type="button" value="Print" onclick="document.getElementById('PDFtoPrint').focus(); document.getElementById('PDFtoPrint').contentWindow.print();"> </form>   What's driving me crazy is: I thought I had this working at one point. The pdf file is showing up in the iframe, but when I click Print, nothing happens.

Can someone please help me out with printing the contents of an IFrame via a javascript call in Safari/Chrome.  This works in firefox:  $('#' + id)[0].focus(); $('#' + id)[0].contentWindow.print();   this works in IE:  window.frames[id].focus(); window.frames[id].print();   But I can't get anything to work in Safari/Chrome.  Thanks  Andrew


i'm very new to Blender so keep in mind that this could completely be my fault ;).    What am I doing wrong, i can't seem to fix this problem. To me it looks like it is a rendering problem, and not a model issue.  I'm using blender on a macbook pro 2016, blender version 2.79b.

Zooming in to inspect texture details in 3D view clips some closer faces like shown in the image. It's not the camera view so changing camera settings doesn't help.   Where can the distance to the clipping plane be adjusted?


the survey is for different online payment methods from which replies for which different methods they are satisfied, not satisfied , can't say.which test is to be done in this question.

I have some  gained from survey questions.  In my case they are  responses (Strongly Disagree-Disagree-Neutral-Agree-Strongly Agree).  In my data they are coded as 1-5.  I  don't think means would mean much here, so what basic summary statistics are considered usefull?


If $(S,.,+)$ is a ring with the property that $a^2 = a$ for all a an element of $S$, which of the following must be true, given:  I $a + a = 0$ for all $a\in{  S}$.  II $(a + b)^2 = a^2 + b^2 $ for all $a, b \in{ S}.$  III S is commutative.   A. III only  B. I and II only  C. I and III only  D. II, and III only  E. I, II, and III   Help please I know that it is not only III so A. is out.

The question is motivated by the following multiple-choice problem:  If $R$ is a ring with the property that $r=r^2$ for each $r\in R$, which of the following must be true? I. $r+r=0$ for each $r\in R$. II. $(r+t)^2=r^2+t^2$ for each $r,t\in R$. III. $R$ is commutative.  Here are my questions:  What theorems do I need to solve the problem above? Why is a ring with the property that $r=r^2$ for each $r\in R$ so special? Is there a name for such rings?


I am visiting Paris from India. The flight is via Munich. There is only a 40 minute gap before departing to Paris from there. So my question is 40 minutes a sufficient time to get the immigration and customs check and still manage to get the Paris flight? Is it possible to do the immigration service check in Paris airport so that I would have sufficient time?

I bought a single ticket from Lufthansa, of Mumbai to Paris. My first flight (LH765) lands at 5:55am at Munich, from where I have another Lufthansa flight (LH2226) to Paris at 6:40am. This is a single ticket so I guess its responsibility of the airline to get me on the second flight, but since it's Non-Schengen to Schengen, will customs etc. be a problem? I am assuming the checked-in luggage would transferred automatically by the airline. Will I be able to make it?


I'm writing a FIR filter that is supposed to calculate  of an input sequence.  class RunningAverager {     public:         RunningAverager(uint64_t FilterOrder)         {             for (uint64_t i=0; i<FilterOrder; i++)             {                 Registers.push(0);             }         }         uint64_t GetAverage(uint64_t NewInput)         {             Registers.push(NewInput);             Registers.pop();             return GetAverage();         }         uint64_t GetAverage() const         {             uint64_t Sum = 0;             //for (uint64_t i=0; i<Registers.size(); i++)       <-- Works             for (std::stack<uint64_t>::const_reference ref=Registers.begin(); ref!=Registers.end(); ???)             {   // begin() and end() methods do not exist for std::stack                 //Sum += Registers[i];      Doesn't work, because the [] operator is not overloaded.                 Sum += ref;             }             return Sum / Registers.size();         }     private:         std::stack<uint64_t> Registers; };   I am having trouble iterating the std::stack object Registers. Unlike other STL containers, it doesn't give an iterator or random access operator.  How do I loop and std::stack object?  An example usage:  RunningAverager ra(10);  while(...) {     FilteredSpeed = ra.GetAverage(ActualSpeed); }

Does the std::stack in the C++ STL expose any iterators of the underlying container or should I use that container directly?


According to Your Dictionary¹:  Abbreviations: St. for Street and Saint, Mr. for mister Acronyms: radar for radio detection and ranging Initialisms: aka for also known as, FBI for Federal Bureau of Investigation  The difference between acronymns and initialisms is that acromyms form new words, while initialisms are pronounces letter-by-letter. People who are familiar with programming, databases, or library science are well familiar with the ID abbreviation, which stands for identifier. But there is another one "thing", UID, which stands for unique identifier. It doesn't look as a pure abbreviation (because there are two words) or a pure initialism (because the first words is trimmed to two letters). So what it is? ¹

IOU stands for I owe you and we pronounce each letter separately. But how do we classify that construction"?   abbreviation: a shortened form of a word or phrase acronym: an abbreviation formed from the initial letters of other words and pronounced as a word Initialism: an abbreviation consisting of initial letters pronounced separately back-formation: a word that is formed from an existing word which looks as though it is a derivative, typically by removal of a suffix      All definitions provided by Oxford Dictionaries Online  It can't be an abbreviation because there is no shortening, clipping or back-formation. Take for example phone which is an abbreviation of telephone, or edit which is a back-formation of editorship and editor. I would argue that abbreviations are words that have been shortened, a faster way of writing or saying something. Another example would be Prof for professor.  It can't be an acronym because we don't pronounce IOU as one word, whereas we do with NATO and RAM.  It can't be an initialism because if it was, it should be written as IOY (I Owe You)  Other examples that spring to mind is CU for see you and YRU for why are you, where initialism would dictate that the proper forms be SY and WAY.   How do linguists define this structure? Is there a more specific term than abbreviation?


I have a table called activation. In here I want to move records older than 30 days to another table. How to do this?   SELECT * DATE_FORMAT(datetime, '%m/%d/%Y')   FROM   tablename   WHERE datetime <= DATE_SUB(SYSDATE(), INTERVAL 30 DAY)   I tried this query but it returns me an error:     You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DATE_FORMAT(datetime, '%m/%d/%Y') FROM activation WHERE datetime <= DATE_SUB(SYS' at line 1

I'm trying to write a query that extracts and transforms data from a table and then insert those data into another table. Yes, this is a data warehousing query and I'm doing it in MS Access. So basically I want some query like this:  INSERT INTO Table2(LongIntColumn2, CurrencyColumn2) VALUES   (SELECT LongIntColumn1, Avg(CurrencyColumn) as CurrencyColumn1 FROM Table1 GROUP BY LongIntColumn1);   I tried but get a syntax error message.  What would you do if you want to do this?


I am using nature class file. In that class, \includegraphics was not working. Which I solved with some modification in the .cls file. However, the captions and labels are not working. Could anyone suggest what is the problem?  Thanks

I wonder how could I modify the nature.cls file to include figures. I comment the last two lines in the nature.cls file, but the compilation returns errors. I submit my .tex, .bib and figures separately to Nature. Now I just want to include figures in my draft and then I can upload my draft in Arxiv. Thank you very much.


The stack exchange sites chose a unique approach regarding who can post answers vs. who can post comments. This occasionally leads to anonymous / low-rep users leaving answers-which-should-have-been-comments simply because adding answers is easy and accessible while adding comments is unexplained on a question page.  I propose to make it clearer to anonymous and low-rep users visiting just the question page that commenting is only available to registered and higher-rep users.  I'm not quite sure how this could be done; I guess it's a good question for . A couple of ideas I've thought about:   Make the "add comment" visible to these users, but make clicking it show a friendly "you have to be registered and with over X rep to add a comment" message. Add a grey "you must be registered and have over X rep to comment on this answer" line in the comment area of each answer.   Optionally, make one of the above visible only when the user hovers over the question/answer area, in a similar way to how the "useful for me" link is displayed.

I just went to comment on , saying something like "hey thanks that solution worked for me; You know anything about extending it to ?"  I was confused why I couldn't find any sort of "add comment* button, and it took me an annoying bit of searching just to find out why. :/  So could us new users see a notification like:     you need a minimum of X reputation to comment on questions that are not your own, and on answers that are not to your own questions   in the space where the add comment button would be?


Making my website responsive I've faced the challenge - I need to move AdSense block, for examlpe: in desktop version of website AdSense adblock is located below the first post of my blog, but in the mobile version - above the first post of my blog.  Usually it's easily solved by using css @media queries  for hiding/showing one of blocks (the one above or the one below). But can I make it with AdSense blocks?  These blocks will have the same slot-id. I think that is breaking the adsense google policy. What alternatives are there to fix this?

I have a responsive blog where ads are displayed in the sidebar. On mobile devices however, the sidebar is pushed to the bottom below the posts.   So what I'd like to do is move the ads from the sidebar and insert them into the post itself on mobile devices   I do this using javascript:

     The ads are always loaded in the sidebar, but if the screen width is below 768px, they will be moved somewhere else.  I wonder if this would violate AdSense terms of service?


Is there any way in which I can either hide the 5.1 and 5.1.1? So I can directly use what I set to the right I would need to do this hiding only for specific subsections /subsubsections

I'm using the report document class for a thesis, and I need to add things like "Acknowledgements" and an "Introduction". I noticed that there is an \abstract command which would have been wonderful if applied similarly. How do I add these without messing up the chapters' numbering while being picked up by the ToC in proper order and page numbering?


I find myself (probably like many others) somewhat unclear on the implications of the postulate of quantum mechanics that "measurements of a value leave the system in an eigenstate". The interpretation of this is clear (if philisophically muddled) for measurements of discrete values such as the energy of an harmonic oscillator in a superposition of energy eigenstates: a single eigenvalue is obtained, and the system is left in the eigenstate corresponding to that eigenvalue, with the probabilities determined by the mod-squared amplitudes of the superposed eigenstates. I find myself unclear, though, on the interpretation of this for the measurement of a continuous value such as position. Clearly, the system cannot be left after measurement in an eigenstate of the position operator, both on the grounds that this would leave it in a complete superpostion of momentum states (which appears to me completely unphysical and not observed in experiment), and that a dirac delta function, while useful conceptually, is not a well behaved and well defined mathematical function that could serve as the physical distribution of some form of real matter. It seems apparent to me that some part of my reasoning here is flawed - either the understanding that measurment leaves a system in an egienstate, or in my understanding of what it would physically mean for a particle to be in an eigenstate of a continuous variable. Help finding the hole would be appreciated!

The way I've understood it is that eigenfunction of an operator are the different states which the actual wavefunction can take when the property/observable corresponding to the given operator is being observed.   For the Hamiltonian operator, the eigenfunctions are forms the wavefunction will take when energy is being measured. The probability that we get a specific state corresponds to the coefficient from fourier decomposition of the wavefunction.   I've also read/interpreted/misinterpreted that upon measurement of position, a wavefunction will collapse to a single spike with a specific value of position (determinate state of the position observable).  With all of the above in mind, is it correct to think that the eigenstates of the position operator are continuous, because the probability density function is continuous and we can get a spike anywhere?  Also, does this mean that the wavefunction takes the form of a spike when position is being observed, but a sine wave when the energy is being observed?  Edit: by continuous eigenstates I want to say that there is an infinite number of them.


The question is, "Fay ------ from her holiday tomorrow evening." Fill the blank with "is returning" or "returns".  Which one would be true if used?

Is there a semantic difference between the following two sentences?     In the future, we are planning to migrate our tool to the Z3 solver.         In the future, we plan to migrate our tool to the Z3 solver.


Original Question  In scrreprt the distance between title and content of a TOC is larger than the distance between a regular chapter title and the text body. Does this make sense in terms of typography? And—if not—how can I prevent this from happening?  Thank you!  Minimal Example    \documentclass{scrreprt} \usepackage{blindtext}  \begin{document} \tableofcontents \chapter{Lorem} \blindtext \end{document}   Edit 1  Well, okay ... I should have looked a bit harder before posting this. According to the answer to , all I need to add is:  \addtocontents{toc}{\vskip -1.0em}   But still: Would you go with the extra vertical space, or would you try to even things out?

With the following example, I get a different vertical distance between "Contents" and "1 bar 5" and "foo" and "Lorem". How do I get the first entry of the TOC to the same height as "Lorem ipsum", that is the base line should be the red rule in the image below:    \documentclass{book} \begin{document} \tableofcontents  \chapter*{foo} Lorem ipsum  \chapter{bar} Lorem ipsum   \end{document}


I want to stretch a DIV-Container inside a div to the height of 100%. The DIV-Container i want to stretch has a image inside via     I also want to center the Image vertically afterwards. I prepared a picture which makes my wishes more clear:    This is my Code right now:

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How can I horizontally center a
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I have to solve the following problem by prooving using Contradiction. The problem is:  Show that for any nonnegative real numbers $a$ and $b$ we have: $\frac {a+b}2 ≥ \sqrt {ab}$  (Sadly, i dont even know where to start for this question)

I am having trouble with this problem from my latest homework.  Prove the arithmetic-geometric mean inequality. That is, for two positive real numbers $x,y$, we have $$ \sqrt{xy}≤ \frac{x+y}{2} .$$ Furthermore, equality occurs if and only if $x = y$.  Any and all help would be appreciated.


I play Minecraft 1.12.2 Java edition. I made a command block that basically shows a welcome intro (ex: Welcome to the world! Please ask  for creative mode.) I want it to repeat about every 30 seconds. I made a HUGE chain of redstone repeaters that takes up A LOT of space. It works, but I was wondering if there was any other easier way.

I tried:  /tp @e[type=ArmorStand,T=100] ~ ~1 ~   Then:  /tp @e[type=ArmorStand,Time=100] ~ ~1 ~   I'm stuck.  I am looking for a command-block only solution.


I've been finding answers on SO for some years now.  However, I always found answers to my questions, so a quick look at SO was always enough. I never felt the need to create an account. Now after these years I thought "give something back", let's upvote good stuff and downvote bad stuff and comment maybe.  However, I can't write comments, I can't upvote, I can't downvote. I can ask questions, but they would be duplicates and give downvotes, bringing me even further from being able to do something. I could try to answer a question, but most of the questions I wouldn't know and the ones I can answer are answered so fast - I would seriously have to sit in front of the screen for hours and hunt for this stuff.  And I am NOT gonna do that. For me SO is a tool to get some work done, not some game to use up some hours of my life.  So, am I missing something or is this account thing really more for a game-like experience? I mean, can't you even answer or ask questions without such an account? I wouldn't need it at all then. Am I actually in the target group for accounts, the way I am using it, or should I just forget about it and go on?  PS Sorry if I may seem upset, but it felt like this to me:   SO: Hey I can help you! Do this and then that.   Me: Ok kewl, thx.   SO: You can also help me, by doing very small things.   Me: Nice, maybe later.   Me: Ok now, let's do it. I thought I owe you a little.   SO: Well I hope you brought lunch, we'll be out there all day.

I have been reading Stack Exchange for years - mostly not logged in, and have never posted (this is my first). I'm simply not very talkative, and very good at googling.  Recently a few occasions have come up when I've wanted to comment on a question.  I wanted either to ask for, or provide, clarification which did not warrant a new answer.  How do I gain enough reputation to comment without:   asking questions which have already been answered or that I can figure out on my own, or posting my comment like as an answer (i.e. being  rude)?


I am writing the makefile of my own code and I realised that when I make the list of my source files I don't include some of them. In fact, what I do is the following:  SRCS = $(wildcard $(SRCS_DIR)*.c) OBJS = $(SRCS:$(SRCS_DIR)%.c=$(OBJS_DIR)%.o)   and them:  $(TARGET): $(OBJS) @echo -e "\n\n\t\t*** Compiled $(TARGET) successfully! ***\n" ; $(FL) $(LFLAGS) -o $(BUILDS_DIR)$@ \     $(OBJS) \     $(LIBS) @echo -e "\n\n\t\t*** Linking $(TARGET) completed! ***\n"  $(OBJS): $(OBJS_DIR)%.o : $(SRCS_DIR)%.c $(CC) $(CFLAGS) $(INCLUDES) \     -c $<\     -o $@   However, some of these files have not the .c but only the header one, ie:     ...common_functions.h     common_macros.h     common_variables.c     common_variables.h     configure.c     configure.h     connectivity.c     connectivity.h     enumerations.h     error_warning_table.c     error_warning_table.h     estimation.c     estimation.h     inout.c     inout.h     ...structures.h  So, of course, when I change something inside of them, they are not compiled again as they are not present in the SRCS list. How can I add them into the SRCS variable? or, how can I create a COMMONS variable with only these files and then compile them?  thanks a lot in advance,  Stefano

I have the following makefile that I use to build a program (a kernel, actually) that I'm working on. Its from scratch and I'm learning about the process, so its not perfect, but I think its powerful enough at this point for my level of experience writing makefiles.  AS  =   nasm CC  =   gcc LD  =   ld  TARGET      =   core BUILD       =   build SOURCES     =   source INCLUDE     =   include ASM         =   assembly  VPATH = $(SOURCES)  CFLAGS  =   -Wall -O -fstrength-reduce -fomit-frame-pointer -finline-functions \             -nostdinc -fno-builtin -I $(INCLUDE) ASFLAGS =   -f elf  #CFILES     =   core.c consoleio.c system.c CFILES      =   $(foreach dir,$(SOURCES),$(notdir $(wildcard $(dir)/*.c))) SFILES      =   assembly/start.asm  SOBJS   =   $(SFILES:.asm=.o) COBJS   =   $(CFILES:.c=.o) OBJS    =   $(SOBJS) $(COBJS)  build : $(TARGET).img  $(TARGET).img : $(TARGET).elf     c:/python26/python.exe concat.py stage1 stage2 pad.bin core.elf floppy.img  $(TARGET).elf : $(OBJS)     $(LD) -T link.ld -o $@ $^  $(SOBJS) : $(SFILES)     $(AS) $(ASFLAGS) $< -o $@  %.o: %.c     @echo Compiling $<...     $(CC) $(CFLAGS) -c -o $@ $<  #Clean Script - Should clear out all .o files everywhere and all that. clean:     -del *.img     -del *.o     -del assembly\*.o     -del core.elf   My main issue with this makefile is that when I modify a header file that one or more C files include, the C files aren't rebuilt. I can fix this quite easily by having all of my header files be dependencies for all of my C files, but that would effectively cause a complete rebuild of the project any time I changed/added a header file, which would not be very graceful.  What I want is for only the C files that include the header file I change to be rebuilt, and for the entire project to be linked again. I can do the linking by causing all header files to be dependencies of the target, but I cannot figure out how to make the C files be invalidated when their included header files are newer.  I've heard that GCC has some commands to make this possible (so the makefile can somehow figure out which files need to be rebuilt) but I can't for the life of me find an actual implementation example to look at. Can someone post a solution that will enable this behavior in a makefile?  EDIT: I should clarify, I'm familiar with the concept of putting the individual targets in and having each target.o require the header files. That requires me to be editing the makefile every time I include a header file somewhere, which is a bit of a pain. I'm looking for a solution that can derive the header file dependencies on its own, which I'm fairly certain I've seen in other projects.


I just commented on a question and I tried to add @BDuelz: in front of it but it got truncated.  How come?

I just posted a comment beginning with @username, and my @username part of the comment disappeared (it was the first word in the comment).  Is there a lolcat inside the Stack Exchange database nomming on notifications? May I suggest you feed it?    P.S. I'm guessing this is a brand spanking new feature, but I can see this coming up a lot


I am making a program where I am inputting the number of cows that I am going to input on the first line. Then I am inputting the cow name, a space, and then a     number (ie:Bessie 4) on each successive line, where I am using a delimiter to parse the string into     the name and the number, then putting it into an array. After that, if the     first cow name is Bessie, then I am adding the associated number value to     the first position of another array, called amountOfMilk, thereby changing     the array value. But when I input Bessie 4, Bessie 5, and Bessie 6 on three    different lines the amountOfMilk array is [0,0,0,0,0,0,0] when it should be    [15,0,0,0,0,0,0].            int[] amountOfMilk = new int[7];         Scanner s = new Scanner(System.in);         int numberOfLogInputs = s.nextInt();         s.nextLine();         for(int i = 0; i < numberOfLogInputs; i++) {            String cowName = s.nextLine();            String delimiter = "[ ]";            String[] tokens = cowName.split(delimiter);            if(tokens[0] == "Bessie") {                amountOfMilk[0] += Integer.parseInt(tokens[1]);            }         }         System.out.println(Arrays.toString(amountOfMilk));

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


Here is the question: Given a fair die rolled $n$ times, what is the probability of having an even number of $6$s?  My approach:  $$\Omega = \{(x_{1}, x_{2}, ..., x_{n}) :1 \le  x_{i} \le 6\}$$ So $$|\Omega| = 6^{n}$$ Since the probability is space is a finite uniform one, $$P(A) = \frac{|A|}{|\Omega|}$$ Let $A_{i}$ be the event that there are exactly $i$ sixes in the $n$-tuple. Then, $$A = \bigcup\limits_{i=0}^{\lceil{(n-1)/2}\rceil} A_{2*i}$$ Since these events are disjoint, $$P(A) = P(\bigcup\limits_{i=0}^{\lceil{(n-1)/2}\rceil} A_{2*i}) = \sum\limits_{i=0}^{\lceil{(n-1)/2}\rceil} P(A_{2*i})$$ Now, $|A_{i}| = \binom{n}{i} * 5^{n-i}$. Hence, $$P(A) = \frac{1}{6^n} \sum\limits_{i=0}^{\lceil{(n-1)/2}\rceil} \binom{n}{2i} * 5^{n-2i}$$ As a side note, when I fed this sum into wolfram alpha engine, it couldn't compute it.  The book however says the anwer is $$\frac{1}{2}(1 + (\frac{2}{3})^{n})$$ Any suggestions?

We throw a fair die $n$ times, show that the probability that there are an even number of sixes is $\frac{1}{2}[1+(\frac{2}{3})^n]$. For the purpose of this question, 0 is even.   I tried doing this problem with induction, but I have problem with induction so I was wondering if my solution was correct:   The base case: For $n=0$, our formula gives us $\frac{1}{2}[1+(\frac{2}{3})^0] =1$. This is true, because if we throw the die zero times, we always get zero sixes.  Suppose it's true for $n=k$. Then the odds of an even number of sixes is $\frac{1}{2}[1+(\frac{2}{3})^n]$, and thus the odds of an odd number of sixes is $1 - \frac{1}{2}[1+(\frac{2}{3})^n]$.    For $n=k+1$, there are two ways the number of sixes are even:  a. The number of sixes for $n=k$ was even, and we do not throw a six for $n=k+1$: $ \frac{5}{6} \cdot  \frac{1}{2}[1+(\frac{2}{3})^n]$  b. The number of sixes for $n=k$ was odd, and we throw a six for $n=k+1$: $\frac{1}{6}(1 - \frac{1}{2}[1+(\frac{2}{3})^n])$  So the probability $p$ for an even number of sixes at $n=k+1$ is $ \frac{5}{6} \cdot  \frac{1}{2}[1+(\frac{2}{3})^n] + \frac{1}{6}(1 - \frac{1}{2}[1+(\frac{2}{3})^n])$  I have two questions   How do I get from $ \frac{5}{6} \cdot  \frac{1}{2}[1+(\frac{2}{3})^n] + \frac{1}{6}(1 - \frac{1}{2}[1+(\frac{2}{3})^n])$ to $\frac{1}{2}[1+(\frac{2}{3})^n]$? I seem to have done something wrong, I can't get the algebra correct, I get $p = \frac{1}{3}[1+(\frac{2}{3})^n] + \dfrac{1}{6}$ Other than that, is my use of induction correct? Is it rigorous enough to prove the formula?


I need to write the following sentence in a description of a book's binding: "Printer's wrappers, housed in a cloth-backed and cloth-edged card slipcase." This seems clunky to me, and I would rather write "cloth-backed and -edged card slipcase." Is the hyphen necessary before "edged?" I know that in the opposite situation (in which the second component is shared between two compound words) one can simply list the first components and follow each with a hyphen. An example I saw in another question was "ground- and sea-based forces." Can the same concept be applied to this situation? Thank you!

If multiple hyphenated terms share the same latter half, and I wish to list them without repeating that latter half, how should the hyphens be placed?  For example:     I will be investigating control issues in ground-based, water-based, and air-based robots.   If I do not want to repeat based, could I write:     I will be investigating control issues in ground-, water-, and air-based robots.   Is it correct to just leave a hyphen dangling after ground and water?  If not, how should it be written? I know the original sentence doesn't sound too bad, but I really just want to know the punctuation rule (or the convention in American English if there is no rule).


I soaked some great northern soup beans for 48 + hours,I started cooking them and they smell  bad,what happened ?

It strikes me as an unsafe food practice to follow Cook's Illustrated's advice for soaking dried beans for 24 hours unrefrigerated.  I've also seen them suggest you soak steel-cut oats unrefrigerated overnight.    Is there some reason why these practices are okay?  Would there be any harm in refrigerating them, particularly the beans, while soaking?  From Cook's Illustrated:     Dissolve 3 tablespoons salt in 4 quarts cold water in large bowl or   container. Add [one pound] beans and soak at room temperature for at least 8 hours   and up to 24 hours. Drain and rinse well.


I'm given that x, y, and A, B are sets, and must prove that the Cartesian product   A x B := {(x, y) | x $\in$ A and y $\in$ B} is a set.  I'm certain that I need to use AC somehow, but I'm having trouble understanding what exactly it would even mean for me to apply it, or how I should go about it.   Here is what believe to understand about AC: if I have a set, say Z = {a, b, c} then applying AC means that I have a function:  f:Z $\mapsto$ $\cup$Z, i.e., f:{a, b, c} $\mapsto$ {{a}, {b}, {c}}   And we have that $\forall$z $\in$ Z (f(z) $\in$ z)  Unfortunately I'm having trouble seeing the consequences of this and how I can extend it to prove that the Cartesian product between A and B is indeed a set. But it could be as well that I've totally misinterpreted the axiom and so obviously can't draw any meaningful conclusions. I would really appreciate if someone could clear the air for me and hopefully set me in the right direction.

In ZFC set theory, every element object is a set. We know or feel that if $X$ and $Y$ are sets, their cartesian product $X\times Y$ is a set.  My question is: Why if $X$ and $Y$ are sets, their cartesian product $X\times Y$ is a set?


Let $R$ be a local commutative Noetherian ring and $M$ a finitely generated $R$-module. We denote by $ \operatorname{Assh}(M)=\{ \mathfrak{p}\in  \operatorname{Ass}(M) \mid \dim R/\mathfrak{p}=\dim M\}.$ Assume that $\operatorname{Ass}(M)=\operatorname{Assh}(M).$ Can we conclude that $M$ is a Cohen-Macaulay $R$-module?   Thank you very much.

Let $R$ be a commutative Noetherian ring with unit and let $I$ be a fixed ideal. I am sorry if the following turns out to be a very silly question.  1) Suppose $\operatorname{Ass}(R/I)$ are all minimal, then what can we say about $R/I$?  One conclusion is that $I$ has a unique primary decomposition. If $R/I$ is CM, then $\operatorname{Ass}(R/I)$ are all minimal, but I don't think the converse is true. Can someone provide a counterexample?  2) Suppose $\operatorname{Ass}(R/I)$ are all minimal and have the same height. I still dont think we can conclude that $R/I$ is CM. Can someone provide a counterexample? Theorem 2.1.6 of Bruns and Herzog, CM Rings, gives a result in this direction but it needs additional hypothesis. It says that if every ideal $I$ is generated by height $I$ elements and $\operatorname{Ass}(R/I)$ are all minimal, then $R$ is CM.  It would be nice if someone can say something nice about the ring in the special situation described in 1) and 2).  Thanks.


I'm traveling to Exeter from Copenhagen via London (Southend) and Dublin (I have no idea why the airplane is landing in Ireland).  I am a Danish citizen with a Danish Passport and all.  Question is, do I need an Airport Transit Visa?  I am traveling on April 13th (March 29th = Brexit 🙄)  This is how I am traveling to Exeter:  Copenhagen -> London Southend Airport (22.25 - 23.55 local time) Ryanair  London Southend Airport -> Dublin Airport (06.55 - 08.10) Ryanair  Dublin Airport -> Exeter Airport (09.55 - 11.05) flybe  PLEASE don't come @ me if it's obvious that I need an Airport Transit Visa 😂  Last time I was in the UK, I was on my way to Egypt, so I needed a Visa for that.  OBS! In Dublin I'm changing Airlines, so have that in mind!

I've got a trip planned to the UK in June. Due to brexit, I'm worried what changes may be introduced before my arrival.  I'm traveling on a EU / Polish passport. I'm going for a couple weeks of holiday.  Is there anything I can do right now to make it less likely any changes won't stop me at the immigration? For example, applying for some tourist visa which does not rely on the EU status?


Say I have these two models:  $y = \beta_0 +\beta_1x_1 + u$    $y = \beta_0 +\beta_1x_1 +\beta_2x_2 + u$  and the $p$ value for $H_0:\beta_1 = 0 $ with $\alpha = 10\%$ for both is less than 0.001, but the $t$ statistic in model 1 is less than the $t$ statistic in model 2.  Does this suggest that model 1 has better evidence for rejecting $H_0:\beta_1 = 0 $ ?  My suspicion is that it doesn't because the whole point of the $p$ value is to have the least level of significance at which at which the null would be rejected, and therefore the concept of "less" or "more" evidence for rejecting becomes meaningless.  Am I totally off or somewhat correct?  Thanks in advance for any help!

I've been reading up on $p$-values, type 1 error rates, significance levels, power calculations, effect sizes and the Fisher vs Neyman-Pearson debate. This has left me feeling a bit overwhelmed. I apologise for the wall of text, but I felt it was necessary to provide an overview of my current understanding of these concepts, before I moved on to my actual questions.    From what I've gathered, a $p$-value is simply a measure of surprise, the probability of obtaining a result at least as extreme, given that the null hypothesis is true. Fisher originally intended for it to be a continuous measure.  In the Neyman-Pearson framework, you select a significance level in advance and use this as an (arbitrary) cut-off point. The significance level is equal to the type 1 error rate. It is defined by the long run frequency, i.e. if you were to repeat an experiment 1000 times and the null hypothesis is true, about 50 of those experiments would result in a significant effect, due to the sampling variability. By choosing a significance level, we are guarding ourselves against these false positives with a certain probability. $P$-values traditionally do not appear in this framework.  If we find a $p$-value of 0.01 this does not mean that the type 1 error rate is 0.01, the type 1 error is stated a priori. I believe this is one of the major arguments in the Fisher vs N-P debate, because $p$-values are often reported as 0.05*, 0.01**, 0.001***. This could mislead people into saying that the effect is significant at a certain $p$-value, instead of at a certain significance value.  I also realise that the $p$-value is a function of the sample size. Therefore, it cannot be used as an absolute measurement. A small $p$-value could point to a small, non-relevant effect in a large sample experiment. To counter this, it is important to perform an power/effect size calculation when determining the sample size for your experiment. $P$-values tell us whether there is an effect, not how large it is. See .  My question: How can I reconcile the facts that the $p$-value is a measure of surprise (smaller = more convincing) while at the same time it cannot be viewed as an absolute measurement?  What I am confused about, is the following: can we be more confident in a small $p$-value than a large one? In the Fisherian sense, I would say yes, we are more surprised. In the N-P framework, choosing a smaller significance level would imply we are guarding ourselves more strongly against false positives.   But on the other hand, $p$-values are dependent on sample size. They are not an absolute measure. Thus we cannot simply say 0.001593 is more significant than 0.0439. Yet this what would be implied in Fisher's framework: we would be more surprised to such an extreme value. There's even discussion about the term highly significant being a misnomer:   I've heard that $p$-values in some fields of science are only considered important when they are smaller than 0.0001, whereas in other fields values around 0.01 are already considered highly significant.  Related questions:         (as provided by @amoeba)


I'm looking for an adjective that says "It's cold, but not that cold".  For example, lukewarm means (in my mind) "It's warm, but not that warm", and I'm looking for its cold counterpart.  Every synonym I find for cold describes an increased cold, not a decreased cold.  Is there any word like this?

Last night, I walked home from my bus stop (in Belgium). Since it was around 11 PM, it was quite cold, probably only about 4-5 °C. However, it didn't actually feel cold at all, and I didn't feel like I had to rush to get home for the cold. In fact, I didn't have headwear on, but I didn't get cold ears. It was about the same temperature as this morning, but the difference is that this morning felt a lot colder, probably due to the wind and drizzle.  I tried to describe it in English on Twitter, but I couldn't actually find a proper word to decribe it. I considered "a warm cold" or "a cozy cold", but I thought these were too poetic, more like something you'd use in a fairy tale than in a tweet to a handful of followers.  How can you describe that temperature without it becoming confusing or poetic?


I'd like to be able to disable the Ubuntu splash screen that I see on boot with the indicator meter of progress, and replace that with a text-only readout of the boot up process (such as you can get by hitting the esc key during the splash screen).  Is this possible?  I am not asking to disable X and get to text-only login, I"m asking how to deactivate the "Ubuntu" loading screen with the dots, so that I can see text output from the boot process - processes being started, kernel messages, etc.  When I wrote this question I was not asking how to disable X altogether, only the boot splash screen.

Is there a way to easily turn on/off showing the boot messages (loading the services) when Ubuntu starts? Is it something in Grub2?  I am running 10.04.


I want to copy all of the files and folders from one host to another. The files are on the old host site at /var/www/html. I only have FTP access to that server, and I can't TAR all the files.  I tried running the following command form my new server:  wget -r ftp://username:password@ip.of.old.host  But the problem is that the username I have is an email address so its not registering it as a username.  For example:  wget -r ftp:// myname@gmail.com:password@ip.of.old.host  This means there are two '@' symbols. I'm not sure but I think it's reading the first @ symbol as the one used in the function. The output Im getting is wget -r ftp://username:password@ip.of.old.host: Bad port number.  Not sure whats going on and any help is appreciated.

Firstly my main goal is to try and get FTP files recursively in Centos.  However the actual FTP login contains an @ which ruins the syntax.  Is there some way to place the username in "double quotes" or some such equivalent such that I can use @in the username?


I want to create a deck of cards by combining a list containing card values:  [7,8,9,10,J,Q,K,A]    and a list containing colors:  [♣,♥,♠,♢]   to get all combinations once.  Is there some simple way to combine lists (or strings) in this way?  I tried several ways but none worked (maybe because special characters used directly (♣,♥,♠,♢) and not in the \N{xxxxx} way? )  expected outcome would be list/dictionary containing all possible combinations exactly once:  ["7♣","7♥","7♠","7♢","8♣","8♥","8♠","8♢", ....."A♣","A♥","A♠","A♢"]   thanks alot for helping guys :)

How can I get the Cartesian product (every possible combination of values) from a group of lists?  Input:   somelists = [    [1, 2, 3],    ['a', 'b'],    [4, 5] ]   Desired output:  [(1, 'a', 4), (1, 'a', 5), (1, 'b', 4), (1, 'b', 5), (2, 'a', 4), (2, 'a', 5) ...]


I am a warlock in a place I am not supposed to be in. I hear someone walking toward the area I am in. I am unsure if they are already close enough to tell that the door is open.  I cast Silent Image on the room and present an image of the room with no one in it. They walk past the doorway, perhaps glancing in perhaps not, but do not see me because the silent image is of the room as it would normally appear. They pass by, and after a few moments I continue snooping. Silent Image Description:  You create the image of an object, a creature, or some other visible phenomenon that is no larger than a 15-foot cube. The image appears at a spot within range and lasts for the duration. The image is purely visual; it isn't accompanied by sound, smell, or other sensory effects. You can use your action to cause the image to move to any spot within range. As the image changes location, you can alter its appearance so that its movements appear natural for the image. For example, if you create an image of a creature and move it, you can alter the image so that it appears to be walking. Physical interaction with the image reveals it to be an illusion, because things can pass through it. A creature that uses its action to examine the image can determine that it is an illusion with a successful Intelligence (Investigation) check against your spell save DC. If a creature discerns the illusion for what it is, the creature can see through the image.   For consideration:   Does the spell Silent Image allow you to cast an image of an empty room, hiding the room's occupants in 5E? Follow-up question: to come

I've been thinking of various ways for a crafty Illusionist/Rogue to 'hide in plain sight' by essentially creating the cover that they want to hide behind.  Ideas include things like:   Create a wall that is 2.5ft closer than it really is and hide in said space Create some innocuous barrier or container and hide within it Create a 'sheet' that essentially has what an empty room looks like 'painted' on it, so someone walking past an open door would see an empty room.   From different discussions I've had, these all should work, but the one lingering one I have is, what if my illusion is simply 'empty space'?  If I were to create an illusion of empty space and then place myself in it, would I be essentially invisible?  What if I created an illusion that was partially-empty space, like a 5x5 cube of swiss cheese? Would it seem like there was a swiss cheese cube formed around my person or could my 'fake-empty-space-image' fill the holes?  Would my 'empty space' illusion simply need to work like the aforementioned 'sheet of what I expect you to see' in order to function (and thus most likely only work from limited viewing angles)?


Hi I have this problem I get this error in the main function: "non static method cannot be referenced from a static context" all of the methods called are underlined with this error. I've tried a few things and I can't find a way to overcome it and it's doing my head in. Is there a way I can get rid of that error? thanks here is the code:  import java.util.Scanner;  public class Survey {  int age; char gender; char show; int over30MY = 0, over30FY = 0, under30MY = 0, under30FY = 0; int over30MN = 0, over30FN = 0, under30MN = 0, under30FN = 0; int totalCalls; int totalWatchers; float perTotalWatchers; float perU30M, perU30F, perO30M, perO30F, perTotalF, perTotalM; float perTotalU30, perTotalO30, perTotal;  public static void main(String[] args) {             System.out.println("Thank you for your call,\nPlease take some time to answer a few questions");     Info();     collectData();     getTotals();     printTotals();  }//end of main  public void Info() { //Prints student Info      System.out.println("");     System.out.println("");     System.out.println("");     System.out.println("");     System.out.println(""); }  public void collectData() {      Scanner userInput = new Scanner(System.in); //Does everything      //ask questions     System.out.println("What is your age?\n");     age = userInput.nextInt();      System.out.println("Male or Female (Enter M or Y)");     gender = userInput.next().charAt(0);     gender = Character.toLowerCase(gender);      System.out.println("Do you watch the show regularly? (Enter Y or N)");     show = userInput.next().charAt(0);     show = Character.toLowerCase(show);      //store data     if((age > 30) && (gender == 'm') && (show == 'y')) {                over30MY++;                  }     else if((age > 30) && (gender == 'f') && (show == 'y')) {         over30FY++;     }     else if((age < 30) && (gender == 'm') && (show == 'y')) {         under30MY++;     }     else if((age < 30) && (gender == 'f') && (show == 'y')) {         under30FY++;     }     else if((age > 30) && (gender == 'm') && (show == 'n')) {         over30MN++;     }     else if((age > 30) && (gender == 'f') && (show == 'n')) {         over30FN++;     }     else if((age < 30) && (gender == 'm') && (show == 'n')) {         under30MN++;     }     else if((age < 30) && (gender == 'f') && (show == 'n')) {         under30FN++;      }//end of if else  }//end of collectData      public void getTotals() {//calculate totals for printing          totalCalls = over30MY + over30FY + under30MY + under30FY + over30MN + over30FN +      under30MN + under30FN;          totalWatchers = over30MY + over30FY + under30MY + under30MN;          perTotalWatchers = Math.round(totalWatchers / totalCalls); //rounds percentage to nearest whole number          perU30F = Math.round(under30FY / totalWatchers); //Total Under 30 Females         perU30M = Math.round(under30MY / totalWatchers); //Total Under 30 Males         perO30F = Math.round(over30FY / totalWatchers); //Total Over 30 Females         perO30M = Math.round(over30MY / totalWatchers); //Total Over 30 Males          perTotalF = Math.round(perU30F + perO30F); //Total Females         perTotalM = Math.round(perU30M + perO30M); //Total Males          perTotalU30 = Math.round(perU30F + perU30M); //Total Under 30         perTotalO30 = Math.round(perO30F + perO30M); //Total Over 30         perTotal = Math.round(perTotalF + perTotalM); //Total       }//end of getTotals      public void printTotals () { //Prints the Totals          System.out.println("Total People called is "+totalCalls);         System.out.println("Number of people who watch the show regularly is "+totalWatchers);         System.out.println("Percentage of those who watch the show is "+perTotalWatchers);                System.out.println("");         System.out.println("");      }//end of printTotals  }// end of class

The very common beginner mistake is when you try to use a class property "statically" without making an instance of that class. It leaves you with the mentioned error message:     You can either make the non static method static or make an instance of that class to use its properties.   Why? I am not asking for solutions. I would be grateful to know what is the reason behind it. The very core reason!  private java.util.List<String> someMethod(){     /* Some Code */     return someList;             }  public static void main(String[] strArgs){                // The following statement causes the error. You know why..     java.util.List<String> someList = someMethod();          }


We have a function $f(x)$ defined on $ [0, +\infty)$.  It is known that $|f'(x)|<2$.  Prove that if $\int_0^{\infty} f(x)\,dx$ converges then $\lim_{x \to +\infty} f(x)=0$.  I don't really know how to use the fact about derivative, I would like to apply LHopital's rule in order to jump from integral to function and then to derivative, but it is not suitable here.

Let $f\colon\mathbb R\to\mathbb R$ be twice differentiable with $f(x)\to 0$ as $x\to\infty$ and $f''$ bounded. Show that $f'(x)\to0$ as $x\to\infty$. (This is inspired by  to a different question)


Does 1<filename have any meaning?Perhaps it means "keyboard -> stdout"?

I ran into notes for a server I used to work on back in the day but the redirection does not look right. Maybe someone can confim?  These were entries in my crontab entered by a third-party vendor who maintained the app/database that ran in this HP-UX server.  15 21 * * 0-6 /usr/sys/bin/stop  q  >/stopout   2<&1 # 30 21 * * 0-6 /usr/sys/force     q  >/out       2<&1 # 55 23 * * 0-6 /usr/sys/start     q  >/startout  2<&1 #   I found this in the Bash manual but this means that stderr and stdout is going out to >/{stopout,out,startout} while stderr is copying stdout (which means stdout is twice being written to stopout,out,startout?)? I'm confused :)  3.6.8 Duplicating File Descriptors The redirection operator  [n]<&word is used to duplicate input file descriptors. If word expands to one or more  digits, the file descriptor denoted by n is made to be a copy of that file  descriptor. If the digits in word do not specify a file descriptor open for  input, a redirection error occurs. If word evaluates to ‘-’, file descriptor n  is closed. If n is not specified, the standard input (file descriptor 0) is  used.


Imagine a spherical ball with radius r that equally coated into two hemisphere P(grey) and S(white) is thrown at the pool. Consider the ball can float (up-down) and rotate. There is an interface separate two different fluid A(air) and B(water). Assume that the interface is flat. α defines the position of the ball and β defines the orientation of the ball. So α larger means ball is more in zone A and vice versa. Range of β and α is $[0,360^0]$ and $[0,180^0]$. The Schematic representation of this is below.   To calculate the surface area of P(grey) coated portion of the ball into A(air) is given by following equation,  $\mathrm{Area}_{P@A}=  r^2\int_{\theta=\frac{\pi}{2}-\beta}^\alpha  \int_{\phi=\arcsin(1/(\tan\theta \tan \beta))} ^{\pi -\arcsin(1/(\tan\theta \tan \beta)} \sin\theta\; d\theta d\phi.$  After solving this equation, we can get the following solution.  $\textrm{Area}_{P@A}= 2 r^2 \left\{ \cos (\alpha) \sin ^{-1}(\cot (\alpha) \cot (\beta)) -\tan ^{-1}\left(\frac{\cos (\beta)}{\sqrt{\sin ^2(\beta)-\cos ^2(\alpha)}}\right)\right\}+\pi  r^2 (1-\cos (\alpha)).$  Note that the solution is defined as a function of α and β. If we change the value of α and β, the area of P coated portion into A(air) will change eventually. Thus we can calculate the area for all valid condition of $\alpha$ and $\beta$.  Now consider a different situation where P and S are not equally coated rather S>P. So I have two spherical cap. Lets assume we know all properties of the cap. Here I show few but if it is necessary we can introduce more.    How can i modify my previous expression if I only want to calculate the  red coloured area? What will be my limit of integration? I have seen  where spherical cap crossing an intersection with some given parameter is shown but in my case my sphere can both rotate and translate. So I need some sort of analytical solution like the hemisphere case where the solution will be a function of rotation and translation.   NOTE: If it is necessary to introduce more parameter, we can do it because of the uniqueness of this problem.

Given a sphere of radius $r$ with two spherical caps on it defined by the radii ($a_1$ and $a_2$) of the bases of the spherical caps, given a separation of the two spherical caps by angle $\theta$, how do you calculate the surface area of that intersection?   To clarify, the area is that of the curved surface on the sphere defined by the intersection. At the extreme where both $a_1,a_2 = r$, we would be describing a spherical lune.   Alternatively define the spherical caps by the angles  $\Phi_1 = \arcsin(a_1/r)$ and $\Phi_2 = \arcsin(a_2/r)$.


I'm not versed in Linux, but my father-in-law gave me Ubuntu 10.10 on a USB, because my Hardrive had failed and I put in a new one. I ran Ubuntu from the USB for a while and decided that I would give it a try and installed it onto my brand new empty hardrive. I now see that I really need to upgrade to a newer version. I thought that I could use the Update Manager and just work my way up the version, but upgrading to 11.04 fails with the message "Failed to fetch, this may be a network problem".   I can download 12.04 and 13.04, but all I get are .iso files. What do I do with them?   Running Wubi.exe doesn't work. I've searched here and can't seem to find an answer which addresses my issue, or at least one written in a way I can understand. Please bear with my inexperience with Linux.    UPDATE: So with further research I have found this:  As a release gets old (especially if it is not a LTS release), it becomes no longer   hosted at archive.ubuntu.com. However, the repository is still hosted at    So try changing your repository source to .  This is great, but I'm now having difficulty finding somewhere that describes "Changing your repository" for a layman. I have found these:  help.ubuntu.com/community/Repositories/Ubuntu  help.ubuntu.com/community/Repositories/CommandLine  But I can't seem to follow how to add the "old releases" url to the repository.

Recently I have installed an older version of Ubuntu on my old machine. Whenever I try to install any software, I get an error saying it couldn't be found:  $ sudo apt-get install vlc Reading package lists... Done                Building dependency tree        Reading state information... Done     E: Couldn't find package vlc


I read the previous answers to this question, and tried to follow, but it does not work. I wanted to add Chromium and Skype to the Startup Applications, but I can't find out what command I should write in there.  I tried the other suggested method: right-clicked on the icon in the Launcher, but there is no item called "Add to the Startup" in the pop-up menu. I am new to Linux and Ubuntu, sorry if there is an obvious answer, please help. Thanks Peter

I frequently need to start several programs that I use every time I start my computer. How can I make it so that whenever I login the program is automatically launched?


I've just got done watching a sub-20 minute run of The Legend of Zelda, Ocarina Of Time and I need to be explained something.  How in the hell can you Warp form the first boss to the last boss. Happens at about 10 minutes in the video below.    I watched the Cosmo Run, but still, can't really understand how that glitch works.  How does it effect the game code in such a way that it warps you from the first boss to a dead Ganon.  Basically, I need an Explain Me Like I'm 5 here.

In Zelda Speedrunning, namely Ocarina of Time, one of the tricks that speedrunners can use is called "wrong-warping". As I understand it, this happens when you go outside of a level and somehow go to some other room I don't know it's confusing.  So, how does this even happen in the first place? And how am I supposed to do it on my own game?


I have lots of windows programs in .exe because i've changed windows 7 to Ubuntu 12.04. Help please

So, I just built my PC today, and am only using Ubuntu until I get Windows installed (sorry, guys!) But when I go to click on any .exe file, nothing happens.  It just sits there.  No error message, nothing.  I've seen other people with similar problems, but they all get an error message.  But not me... Whats going on?  How do I fix this?  Help?


I have the following code  final List<ItemDto> itemDtos = result.getResults(); List<String> deleteItemIds = new ArrayList<String>();  // remove items which have been deleted on the server for(ItemDto itemDto : itemDtos) {   if (itemDto.getIsRemoved()) {     deleteItemIds.add(itemDto.getId());     itemDtos.remove(itemDto);  //  TODO not sure if this works here   } }   I iterate over the itemDtos and remove an ItemDto at the last operation in the for loop. I think that this works if I do not need something like itemDtos.indexOf(o)inside the loop.   Is the code I did correctly working?  Edit: Here is a second variant:   List<ItemDto> itemDtos = result.getResults(); List<ItemDto> tmpList = itemDtos; List<String> deleteItemIds = new ArrayList<String>();  // remove items which have been deleted on the server for(ItemDto itemDto : tmpList) {   if (itemDto.getIsRemoved()) {     deleteItemIds.add(itemDto.getId());     itemDtos.remove(itemDto);  //  TODO not sure if this works here   } }   Is the second variant better?

We all know you can't do the following because of ConcurrentModificationException:  for (Object i : l) {     if (condition(i)) {         l.remove(i);     } }   But this apparently works sometimes, but not always. Here's some specific code:  public static void main(String[] args) {     Collection<Integer> l = new ArrayList<>();      for (int i = 0; i < 10; ++i) {         l.add(4);         l.add(5);         l.add(6);     }      for (int i : l) {         if (i == 5) {             l.remove(i);         }     }      System.out.println(l); }   This, of course, results in:  Exception in thread "main" java.util.ConcurrentModificationException   Even though multiple threads aren't doing it. Anyway.  What's the best solution to this problem? How can I remove an item from the collection in a loop without throwing this exception?  I'm also using an arbitrary Collection here, not necessarily an ArrayList, so you can't rely on get.


I was just going through Neural-Network tutorials and I have some question regarding Bias neuron :-  1.] Is the act of introducing bias neuron same as introducing the X(index 0)=1 in the logistic regression i.e. [1, X1, X2]  2.] Is bias neuron an additional degree of freedom ?  3.] Can bias neuron be analogous to the constant term in  the linear equation :-  Y= mX+C   because without C i can only rotate the line x around the origin, but if I take into consideration C also then I can translate this line up or down also.  For example consider the figure below :-    Then the blue line (hypothesis) is simply Y=m*X (blue line passes through origin), so even if you keep fiddling with the m paramater but you wont be able to seperate the green and blue dots ever with just this hypothesis. So with just m to fiddle with, my hypothesis will always have to pass through the origin, i.e. I can choose from the infinite numbers of lines through the origin by tweaking the parameter 'm'.  Whereas if I include C/constant term (which Im calling the bias) in my hypothesis then my equation becomes Y=m*X+C then a line like Y=.4*X+3  (magenta line ) easily classifies the data. So now that I have an additional parameter "C" , I can translate(shift up/shift down) apart from the rotation.  Is my understanding correct ?

I'm curious to know how important the bias node is for the effectiveness of modern neural networks. I can easily understand that it can be important in a shallow network with only a few input variables. However, modern neural nets such as in deep learning often have a large number of input variables to decide whether a certain neuron is triggered. Would simply removing them from, e.g., LeNet5 or ImageNet have any real impact at all?


I have to work with a shapefile defined in an unusual projection, which my GIS software does not know about. How can I get the proj4 definition or the EPSG code for the projection?

I was wondering if there is such a thing as an shapefile PRJ to PostGIS SRID lookup table?  Something that can translate the most standard shapefile PRJ definitions into the likely SRID.  When using PostGIS and pgAdminIII, if you use the postgisgui to import your shapefiles, the SRID is left as "-1".  It seems like the tool should be able to parse the Esri PRJ and determine the correct (or at least a couple of options) that are the likely SRID, rather than just leave the default.  Or does the importer have the capability to reproject on the fly if you choose another SRID?  It may seem lazy on my part, but to me it seems curious that this function hasn't already been put in place.  Does anyone know if this concept is in the works, or good reason's why it has been left out?


So I'm starting a medical practice, and creating a website for it. We don't want to do a blog, as we see no need to duplicate information out there, and we can't resource ongoing. Yet if we don't have regularly updated content, I'm concerned that we'll slide down the SERPs.  How can we rank high without fresh new content? I'm thinking of the following:   solid linking strategy regular social media posts ensure relevant content on website (and updated regularly), but no blog.   Your thoughts? Should we just do a blog regardless? I don't want to lose ground for our SERPs, or shoot myself in the foot.

What are the best ways to improve a site's position in the Google search results?


I want to deliver cron generated emails to my id, abc@example.com instead of being saved on /var/spool/clientqueue  I've done the following:  echo "set smtp=smtp.example.com" > /root/.mailrc echo "set from=abc@exmaple.com" >> /root/.mailrc  but nothing happen.   Any help ??  No I don't want to run MTA on my machine. I want to using external smtp instead of running a smtp on my machine. this is what i want.  I don't want to use postfix or sendmail. I want to use a smtp server as normally we use smtp in outlook express as outgoing server. Same like that i want to use an external smtp for cron.  I want to deliver emails on behalf of other MTA which would be use as smtp for all of the emails delivery.

I would like to have cron output sent to an external email address, via a minimal SMTP client that sends via Gmail. I think I need this client to support TLS and /etc/aliases, and I would like configuration to be as simple as possible.


I mounted my windows partition folders such as Documents, Downloads, Music and etc. to Ubuntu 15.10. It works ok but after I reboot my computer they are not available until I click at windows partition volume in Files. It is kinda annoying. How to make them available right after system is restarted?

How do you make HDDs and partitions mount at startup on Ubuntu?  I always keep my media and data files on separate partitions - one 2tb HDD and a 400 odd gig partition.  I have been trying to swap the default folder location for the home directory to my other drives.  It works when I change the /home/user_name/.config/user-dirs.dirs file to the directories I want, but only until I reboot the system. I am only assuming that the drives not mounting is the problem with it, but it would be helpful either way.  If any one knows another reason for why the directories change back to default each time that would be good also.


I've been looking for a general word to define an idea that seems true, but simply isn't. A simple example: "The Earth is flat."  If all you know is the world outside your window, and you've never done any basic experiments, read books, or seen photos to the contrary, this seems like a reasonable explanation.  But it doesn't take too much more examination to find out that it  just isn't so. The key point here is that it's something a reasonable person could reasonably believe. The closest I've come to what I'm looking for is "verisimilitude."  I looked at , but it seems to me that words like "spurious" or "nonsense" seem to imply some ill-intent to deceive, which is not what I'm after.  (Or maybe it's more a concept than a word, and that's ok too, if anyone has thoughts on that.)

In Greek, λογικοφανής is a word that describes a person who spits out seemingly logical statements. It often has a negative connotation as it is targeted towards people who tend to fool the public with supposedly beautifully-constructed thoughts that sound convincing in our ears but are not necessarily accurate. The first word that comes to mind is deceptive, but it is not quite what I look for. Any thoughts?


I has happened 4 times now, I change some setting, delete the sheet open in the app from the PC, create a wrong function, and from then on, the Google Drive app crashes on start. I can not close the faulty document, so it keeps happening until I remove the application. You would think a restart of the phone should help, but it does not.  Is there a setting somewhere that lets me open the list instead of the most recent document?

I have an application that isn't working correctly. Either it's not launching, or not responding to commands, or some of the functionality isn't doing what I expect.  What are some simple steps I can do to try to fix the issue on my own?  (This question and answer are intended to be a canonical and generic source for dealing with apps that aren't working quite right.)


The question might sound like an old one but I haven't got satisfactory answers for a number of questions I have about CV. I looked at several questions on CV , ,  and  and yet things aren't very clear to me. So I will post a few questions which are related and hopefuly will help me (and other people) understand CV better.   Say I use K-fold CV for a learner (say linear regression). In the process, I learn K different sets of regression parameters. For each set of params, I know the error on the corresponding validation set. Now what do I do? Which of those K sets of learned params should I select? Do I retain the params set which gave the least error? Or should I now learn a new model with all training data together (in which case, why did I do CV in the first place)? Does CV help avoid overfitting? Is this true in all cases or is it true only for specific type of learners (like Decision trees)? How does CV avoid overfitting if the above is true in general for any learner? Is CV needed only for small datasets or also for large datasets (think big data scale)? If the purpose of CV is to get a better estimate of the prediction error (and assuming we have a large test set), why shouldn't we just use a fixed training set, and a number of disjoint test subsets, averaging the errors across all test subsets?

How would you describe  to someone without a data analysis background?


Actually we can prove the statement in the reverse way.  Here $a$ is non zero element, $F$ is a field.  Suppose $f(x)$ is reducible then $f(x) = g(x)h(x)$, then $f(x+a)= g(x+a) h(x+a)$.  But I can't understand what it exactly wants to convey.  It's an exercise problem from Joseph Gallion Algebra under Factorization of Polynomials.

Let $A$ be a field and let $p(X)$ be a polynomial over $A$. Let $a\in A$.   Want to show:     $p(X)$ is irreducible if and only if $p(X+a)$ is irreducible.    I suspect that I should use the substitution principle somehow, but that's as far as I've come. Completely stumped.


Suppose $f:\mathbb{R} \to \mathbb{R}$ is a differentiable function such that $\lim\limits_{x\to\infty}f'(x)=1$,then is it true necessarily true that $f(x)$ unbounded?   I think that it will always intersect $y=c$ for every $c\in \mathbb{R}$ and thus cannot be bounded!

Question is :  For a differentiable function $f:\mathbb{R} \rightarrow \mathbb{R}$ what does $\lim_{x\rightarrow +\infty} f'(x)=1$ imply?  Options:    $f$ is bounded $f$ is increasing $f$ is unbounded $f'$ is bounded   I could not find counter examples but then, I strongly feel $\lim_{x\rightarrow +\infty} f'(x)=1$ would just imply that $f'(x)$ is bounded.  I do not have much idea why would other three are false.  I would be thankful if someone can suggest me some hints.  Thank You.


The title says it all, here is the code:  \documentclass{article} \usepackage{tikz} \usetikzlibrary{shapes,backgrounds} \begin{document}  \def\lcirc2{(-.7,-.5) circle (1cm)} \def\rcirc2{(.7,-.5) circle (1cm)} \def\ucirc{(0,.5) circle (1cm)} \def\rect{(-2.5,-1.8) rectangle (2.5,1.8)} \begin{tikzpicture}   \begin{scope}     \clip \rcirc2;     \fill[gray] \rcirc2;     \fill[white] \lcirc2;     \fill[gray] \ucirc;   \end{scope}   \begin{scope}     \clip \lcirc2;     \fill[gray] \lcirc2;     \fill[white] \rcirc2;   \end{scope}   \begin{scope}     \clip \ucirc;     \fill[gray] \ucirc;   \end{scope}   \draw \rect;   \draw \lcirc2;   \draw \rcirc2;   \draw \ucirc;   \draw (0,2.1) node {$(A\bigtriangleup B)\bigtriangleup C$};   \draw (0,-.2) node {$X$};  \end{tikzpicture} \end{document}     I need to shade X gray in addition to each circle without the other. Thanks in advance.

but now my question is more complicated than just drawing Venn diagrams one by one. I need to draw all possible Venn diagrams efficiently. I need a combinatorical approach because there are 256 combinations.  Let's choose the following sets  as the case to consider. The binary number labels are used to uniquely identified each "atomic" region. My definition: An atomic region does not contain any smaller region.  Because there are 8 atomic regions, each can be either selected or not to compose a new compound region. Therefore there are 2^8 ways.  How to generate all possible Venn diagrams (with the case above) efficiently?    The objective is to produce 256 Venn diagrams, each diagram has a unique colored compound region that has an associated set operation.   Let's use 8-bit integer to represent each diagram.  The first bit (the most left bit or the most significant bit) represents the region 000.  The second bit represents the region 100.  ...  The least significant bit represents the region 111.  Bit 0 represent not-join to produce a new compound region. And 1 otherwise.  If the first diagram with the complement of AuBuC then its binary representation is 1000 0000. 1111 1111 represents S. Etc etc etc!  The Problem Sheet  The problem sheet will ask the student to find a set operation (not necessarily unique) for each RED COMPOUND region in each diagram below.      ...


proof or disprove :If p is a prime number of 5 or more, there is no integer n satisfying $p + 1 = n^2$  first attempt: suppose $p>5$ and $p$ is prime and prove that there is no n integer that satisfy $p+1=n^2$. let $ p=7$, $n= \sqrt {p+1}$ , $n= \sqrt 8$ and is not integer   i think this proof is wrong? because i only proved for p=7  second attempt: let $p=n^2-1 $,$ p=(n+1 )(n-1)$, since $p$ is prime and bigger than 5 by assumption , $n-1=1$, $n=2$, $p=3.2$ , this contradict the fact that p is prime and bigger than 5, hence there is no integer n that satisfy $p + 1 = n^2$ is this looks fine?  now im trying to proof by contrapositive, there is n integer satisfy $ p+1=n^2$ and trying to proof p is prime and p<5  $n=\sqrt {p+1}$ , suppose $p=3$ ,$ n= \sqrt 4$, $n=2$ so there is n integer  satisfy $p+1=n^2$, hence If p is a prime number of 5 or more, there is no integer n satisfying $p + 1 = n^2$  please give review thanks! if im not sure that the proposition is correct, how can i proof by contradiction ?

Prove or disprove: For a prime number p, there is a positive integer n such that $p+1 $= $n^2$ if and only if $ p = 3.$  first im trying to proof if p is prime number there is positive integer n such that $p+1=n^2$ implies $p=3$  suppose there is positive n integer such that $p+1=n^2$ and prove that $p=3$. $p=n^2-1=(n+1)(n-1)$ since $p$ is prime $n-1=1$,$ n = 2 $ $p+1=4$ $p=3$ hence it is proved that $p=3$  now if $p=3$ implies there is positive integer n such that $p+1=n^2 $  $p=3$ and p is prime  $p+1=n^2$, $4=n^2$, $n2$ or $n=-2$ hence it is proved that there is positive integer $n$ such that $p+1=n^2 $  is my proof correct? and also for prime number can i write $n+1=1$ instead $n-1=1$?


Is there a declaration/assign function in MATLAB or Python which works in both ways, bilateral/mirror type of use? Example;  x = 3 print x #output is 3#   but what if there is a type of function, like this;  x _=_ 3 print x # output is 3 # print 3 # output is x #

I was working with a new C++ developer a while back when he asked the question: "Why can't variable names start with numbers?"  I couldn't come up with an answer except that some numbers can have text in them (123456L, 123456U) and that wouldn't be possible if the compilers were thinking everything with some amount of alpha characters was a variable name.  Was that the right answer?  Are there any more reasons?  string 2BeOrNot2Be = "that is the question"; // Why won't this compile?


Setting:  Let $a\in \mathbb{R}$, and let $f$ be a function which is continuous on $\mathbb{R}$, differentiable on $(\infty,a)\cup (a,\infty)$, and has the property that $\lim_{x\to a^{-}}f'(x) = \lim_{x\to a^{+}}f'(x) = L$ for some $L\in\mathbb{R}$.  Question:  Does it automatically follow that $f$ is differentiable at $a\in \mathbb{R}$?  My intuition wants to say yes since we are placing such strong conditions on $f$, and if I were going to try to prove this I would pursue the following logic:  Argument:  \begin{align*} f'(a) &= \lim_{h\to 0}\frac{f(a+h) - f(a)}{h}\\ &= \lim_{h\to 0}\left[\lim_{x\to a^{-}}\frac{f(x+h) - f(x)}{h}\right]\text{using continuity of} f \text{at }a\\ &= \color{red}{\lim_{x\to a^{-}}\left[\lim_{h\to 0}\frac{f(x+h) - f(x)}{h}\right]}\\ &= \lim_{x\to a^{-}}f'(x)\\ &= L \end{align*}  or using essentially the same argument from the other side.....  \begin{align*} f'(a) &= \lim_{h\to 0}\frac{f(a+h) - f(a)}{h}\\ &= \lim_{h\to 0}\left[\lim_{x\to a^{+}}\frac{f(x+h) - f(x)}{h}\right]\text{using continuity of} f \text{at }a\\ &= \color{blue}{\lim_{x\to a^{+}}\left[\lim_{h\to 0}\frac{f(x+h) - f(x)}{h}\right]}\\ &= \lim_{x\to a^{+}}f'(x)\\ &= L \end{align*}  But the steps that I've outlined in red and blue correspond to geniune gaps in my argument.  We cannot always interchange such limits without caution, but perhaps due to the strong assumptions on $f$ we can in this case.  Is there an example of a function $f$ (of course, satisfying the conditions give above) for which this logic fails?  If not, how can I fix my argument?

Suppose we have a continuous function $f : \mathbb{R} \to \mathbb{R}$. Suppose also that for a certain point $c$, $\lim_{x \to c} f'(x)$ exists. Must $f'(c)$ exist as well, and be equal to this limit?  This isn't quite the same as asking if derivatives are always continuous. The well-known function $f(x) = x^2 \sin (1/x)$ is continuous and differentiable everywhere, but its derivative has no limit at $x = 0$. I'm wondering if the derivative of a continuous function can have a discontinuity where its limit does exist.


In most Emacs major modes targetting compiled programming languages, C-c C-c invokes make. In AucTeX, it lets me choose between any of  BibTeX  Biber   Check   ChkTeX  Clean   Clean All   File Index   LaTeX   Other   Print   Queue   Spell   View Xindy   These options are generally fine, but sometimes compiling my document requires more complex steps; in these cases, I use a Makefile.  How can I extend the list displayed by AucTeX to include a Make option?  TeX-command-list and TeX-run-compile seem relevant, as C-c C-c invokes TeX-command-master, which presents entries from `TeX-command-list.

I am editing my PhD thesis using Emacs & Auctex, but my elisp is quite weak. Additionally, I build my thesis in a subdirectory, using makefiles generated by CMake and the UseLATEX CMake package, which I highly recommend.  I can’t figure out how to tell auctex that when I build the document it should do something like: make -C build/digital and that the pdf file being output is going to be at build/digital/thesis.pdf even though the source is at ./thesis.tex  p.s. I HIGHLY recommend checking out UseLATEX, the CMake package for easily compiling LaTeX documents.


From pydoc:     re.sub = sub(pattern, repl, string, count=0, flags=0)       Return the string obtained by replacing the leftmost       non-overlapping occurrences of the pattern in string by the       replacement repl.  repl can be either a string or a callable;       if a string, backslash escapes in it are processed.  If it is       a callable, it's passed the match object and must return       a replacement string to be used.   example code:  import re print re.sub('class', 'function', 'Class object', re.I)   No replacement is made unless I change pattern to 'Class'.    Documentation doesn't mention anything about this limitation, so I assume I may be doing something wrong.    What's the case here?

The Python docs say:     re.MULTILINE: When specified, the pattern character '^' matches at the beginning of the string and at the beginning of each line (immediately following each newline)... By default, '^' matches only at the beginning of the string...   So what's going on when I get the following unexpected result?  >>> import re >>> s = """// The quick brown fox. ... // Jumped over the lazy dog.""" >>> re.sub('^//', '', s, re.MULTILINE) ' The quick brown fox.\n// Jumped over the lazy dog.'


I am using the VI editor in Ubuntu and I have maximum usage of VI editor. to see the line number in vi i am using like below:  :set nu    I want to set it default when I open a file in vi editor, that file text open with line number by default.  is it possible?  Sorry for duplicate's if it but I search it lot first but not found easily also tried :colorscheme now it is showing me unknown

How do I change default settings of Vim editor such as setting auto indent, setting Tab space to 4 and changing text colors? Also how to set vim as the default code editor?


Let $N $ be a normal subgroup of order $p$ contained in a group $G$ of order $p^n$. Here $p$ is a prime number. Then I have to show thst $N$ is in the center of $G$.  This is an exercise 15 in p.92 of Hungerford.   I thought of acting $G$ on $N$ but cannot find a way through.  Could anyone please help me?

If a normal subgroup $N$ of order $p$($p$ prime) is contained in a group $G$ of order $p^n$,then $N$ is in the center of $G$.   I want to use induction to prove this:  It is trivial when $G=p(n=1)$, assume $G=p^n$, $N$ is a normal subgroup in $G$ with order $p$. Since $G$ is p-subgroup, $G$ has a normal subgroup $H$ with order $p^{n-1}$,according to assumption, $N \subset C(H)$. But I don't know how to go on, is $C(H)=C(G)$?Can induction work in this case?