Answers.Body: <p>What do you want to do with NA values?</p>
  
  <p>The below scripts ignore them (h3ab74's answer will print them to positiveExpression)</p>
  
  <pre><code>awk '<span class="math-container">$2 ~ /^[0-9]+$</span>/  {print <span class="math-container">$0}' expressionFile.txt &gt; positiveExpression.txt
  awk '$</span>2 ~ /^-[0-9]+<span class="math-container">$/ {print $</span>0}' expressionFile.txt &gt; negativeExpression.txt
  </code></pre>
  
  <p>These do a regex match to respectively, positive and negative numbers. If there's anything else in field 2 the line won't be printed. </p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-01T12:21:53.193Z
Answers.LastActivityDate: 2020-06-01T12:21:53.193Z
Answers.UserDisplayName: Greg
Answers.Body: <pre><code>awk '{if(<span class="math-container">$2&gt;0) print $</span>0}' expressionFile.txt &gt;&gt; positiveExpression.txt
  awk '{if(<span class="math-container">$2&lt;0) print $</span>0}' expressionFile.txt &gt;&gt; negativeExpression.txt
  </code></pre>
  
  <p>Assuming that the file with gene expressions has the title: expressionFile.txt, this should do the trick.</p>
  
  <p>Explanation of first line of code: if values in the 2nd column - <code>$2</code> - are greater than 0, print all columns (<code>$0</code>) and write to a file (<code>&gt;&gt;</code>) titled, positiveExpression.txt. The use of <code>awk '{}'</code> is just syntactical. </p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-05-30T14:56:29.860Z
Answers.LastActivityDate: 2020-05-30T15:01:45.293Z
Answers.LastEditDate: 2020-05-30T15:01:45.293Z
Answers.UserDisplayName: h3ab74
Body: <p>I have a file like this with 2 columns. I want to separate the columns based on plus and minus signs into separate files. How do I do this with awk or sed. Kindly help.    </p>
  
  <p><a href="https://i.sstatic.net/my8CN.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/my8CN.png" alt="enter image description here"></a></p>
  
Tags: <text-processing><awk>
Title: separate genes with expression values
ThreadText: # separate genes with expression values
  
  (Asked by: username_0 on 2020-05-30)
  
  I have a file like this with 2 columns. I want to separate the columns based on plus and minus signs into separate files. How do I do this with awk or sed. Kindly help.
  
  [![enter image description here](https://i.sstatic.net/my8CN.png)](https://i.sstatic.net/my8CN.png)
  
  **Tags:** text-processing, awk
  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_1 on 2020-06-01. Score: 3 | Accepted answer
  
  What do you want to do with NA values?
  
  The below scripts ignore them (username_2's answer will print them to positiveExpression)
  
  ```
  awk '$2 ~ /^[0-9]+$/  {print $0}' expressionFile.txt > positiveExpression.txt
  awk '$2 ~ /^-[0-9]+$/ {print $0}' expressionFile.txt > negativeExpression.txt
  
  ```
  
  These do a regex match to respectively, positive and negative numbers. If there's anything else in field 2 the line won't be printed.
  
  
  ---
  
  ### Answer by username_2 on 2020-05-30. Score: 1
  
  ```
  awk '{if($2>0) print $0}' expressionFile.txt >> positiveExpression.txt
  awk '{if($2<0) print $0}' expressionFile.txt >> negativeExpression.txt
  
  ```
  
  Assuming that the file with gene expressions has the title: expressionFile.txt, this should do the trick.
  
  Explanation of first line of code: if values in the 2nd column - `$2` - are greater than 0, print all columns (`$0`) and write to a file (`>>`) titled, positiveExpression.txt. The use of `awk '{}'` is just syntactical.
  
  
  ---
  
  