<p>I don't think swisseph has that capability, but skyfield.searchlib.find_discrete() is made for this sort of thing.
You would need to pass it a function which returns an integer indicating whether the node longitude at a given time is east or west of the value you're searching for.
<a href="https://rhodesmill.org/skyfield/searches.html" rel="nofollow noreferrer">The documentation</a> and an <a href="/a/54642">answer here</a> have relevant examples.</p>

CC BY-SA 4.0
2023-10-03T19:50:11.870Z
thank you Mike, i really appreciate it <3
dimitri33
CC BY-SA 4.0
2023-10-05T22:38:36.127Z
hey Mike G, can you give me another hint with this please ... i can't even sleep as i keep going over this thing :(  https://pastebin.com/NBUMFrtH
dimitri33
CC BY-SA 4.0
2023-10-06T04:00:05.713Z
1. observe from Earth instead of the Sun;
2. let function return ((observed_longitude - longitude) // 180).astype(int) % 2;
3. step_days = ~1/4 of the expected period;
4. filter longitude_times by in_state == 0
Mike G
CC BY-SA 4.0
2023-10-06T04:24:42.377Z
https://pastebin.com/dcUDALrB
dimitri33
CC BY-SA 4.0
2023-10-06T04:35:04.780Z
That code looks at the longitude of the Moon itself and should find 12 or 13 crossings per year. Now try looking at its [orbital elements](https://rhodesmill.org/skyfield/elements.html).
Mike G
CC BY-SA 4.0
2023-10-06T18:11:01.113Z
https://pastebin.com/z5S4HjCQ .... Not getting it, however I did played with the documentation that you posted first. I like that <3 however been a noob can be frustrating as hell  :)
dimitri33
CC BY-SA 4.0
2023-10-03T17:16:56.850Z
2023-10-03T17:16:56.850Z
Mike G
<p>It appears that that swetest can tell the exact longitude as long as you give it the date and time</p>
<pre><code>./swetest -pt -b17.11.2023 -ut22:43
date (dmy) 17.11.2023 greg.   22:43:00 UT        version 2.10.03
UT:  2460266.446527778     delta t: 69.109781 sec
TT:  2460266.447327659
Epsilon (t/m)     23°26'18.3245   23°26'10.2223
Nutation          -0° 0' 7.8330    0° 0' 8.1021
true Node         24°29'59.7465    0° 0' 0.0000    0.002502442   -0° 3'35.2933
</code></pre>
<p>Now my question is can one get the time and date for the nodes if it gives the longitude  lets say <code>24.5</code> same as the one in the swetest example .. can we calculate using swisseph, kind a like how solcross does  or mooncross ?  I only need a little hint on how to do it .. thank u &lt;3</p>

CC BY-SA 4.0
2023-10-02T02:17:34.230Z
The ``` has to go on a line by itself.
Mike G
<the-moon>
North Node cross longitude?
dimitri33
# North Node cross longitude?

(Asked by: username_0 on 2023-10-01)

It appears that that swetest can tell the exact longitude as long as you give it the date and time
./swetest -pt -b17.11.2023 -ut22:43
date (dmy) 17.11.2023 greg.   22:43:00 UT        version 2.10.03
UT:  2460266.446527778     delta t: 69.109781 sec
TT:  2460266.447327659
Epsilon (t/m)     23°26'18.3245   23°26'10.2223
Nutation          -0° 0' 7.8330    0° 0' 8.1021
true Node         24°29'59.7465    0° 0' 0.0000    0.002502442   -0° 3'35.2933

Now my question is can one get the time and date for the nodes if it gives the longitude  lets say 24.5 same as the one in the swetest example .. can we calculate using swisseph, kind a like how solcross does  or mooncross ?  I only need a little hint on how to do it .. thank u <3

**Tags:** the-moon
> **Comments:**
> **username_1**: The ``` has to go on a line by itself.  

---

## 1 answers

### Answer by username_1 on 2023-10-03. Score: 1 | Accepted answer

I don't think swisseph has that capability, but skyfield.searchlib.find\_discrete() is made for this sort of thing.
You would need to pass it a function which returns an integer indicating whether the node longitude at a given time is east or west of the value you're searching for.
[The documentation](https://rhodesmill.org/skyfield/searches.html) and an [answer here](/a/54642) have relevant examples.

> **Comments:**
> **username_0**: thank you Mike, i really appreciate it <3  
> **username_0**: hey Mike G, can you give me another hint with this please ... i can't even sleep as i keep going over this thing :(  https://pastebin.com/NBUMFrtH  
> **username_1**: 1. observe from Earth instead of the Sun; 2. let function return ((observed_longitude - longitude) // 180).astype(int) % 2; 3. step_days = ~1/4 of the expected period; 4. filter longitude_times by in_state == 0  
> **username_0**: https://pastebin.com/dcUDALrB  
> **username_1**: That code looks at the longitude of the Moon itself and should find 12 or 13 crossings per year. Now try looking at its [orbital elements](https://rhodesmill.org/skyfield/elements.html).  
> **username_0**: https://pastebin.com/z5S4HjCQ .... Not getting it, however I did played with the documentation that you posted first. I like that <3 however been a noob can be frustrating as hell  :)  

---

