title: Use part of a column in one file as search term in other file
body: <p>I have two files. The output file I am searching has earthquake locations and has the following format:</p>
  
  <pre><code>19090212 1323 30.12 36 19.41 103 28.24   7.29   0.00  4 149 25.8 0.02  5.7  9.8 D -         0
  19090216 1828 49.61 36 13.27 101 35.38  10.94   0.00 13  54 38.5 0.07  0.3  0.7 B           0
  19090711 2114 54.11 35  1.07  99 56.42   7.00   0.00  7 177 18.7 4.00 63.3 53.2 D #         0
  </code></pre>
  
  <p>I want to use the last 6 digits of the first column (i.e. '090418' out of '19090418') with the first 3 digits of the second column (i.e. '072' out of '0728') as my search term. The file I am searching has the following format: </p>
  
  <pre><code>SC17 P   090212132329.89
  X25A P   090212132330.50
  
  AMTX P   090216182814.12
  X29A P   090216182813.70
  Y28A P   090216182822.36
  MSTX P   090216182826.80
  Y27A P   090216182831.43
  </code></pre>
  
  <p>After I search the second file for the term, I need to figure out how many lines are in that section. So for this example, if I were searching the terms shown for the second file above, I want to know there are 2 lines for 090212132 and 5 lines for 090216182.</p>
  
  <p>This is my first post, so please let me know how I can improve clarity or conciseness in my posts. Thanks for the help!</p>