title: How do I delete columns from a matrix based on a list in R?
body: <p>I have a very large matrix that looks like this:</p>
  
  <pre><code>        AGAG      AAGAA     AGTG     AGAT     AAGAT     AGTT       
  1001    14691      0          0        0        0        5
  1002    13        12          0       5831     20473     4
  1003    0        5831      20473       0        0        0
  1004    0        7936       7936      7936      0        0
  1005    16066      0         0         24       2        2
  </code></pre>
  
  <p>There are >8000 columns. I need to delete many (~3000) of these columns by the column name. I have abbreviated the column names here (genome sequences). Obviously, I can't type that many individually.  </p>
  
  <p>I made a separate table that has the column names I want to delete. For example:</p>
  
  <pre><code>AGAG
  AGTG
  AGTT 
  AGAT  
  </code></pre>
  
  <p>I tried to use subset and %in% so far to no avail.</p>