Use Notepad++ for comparing lists

When processing hundreds or thousands of LiDAR LAS files or aerial photographs, sometimes one or more files may not get processed and missed out from the processing flow. It is useful to be able to identify which files did not get processed so that they can be reprocessed again. There are many ways to compare and one such method is using Notepad++, a free text editor. There is a free plug-in Compare for Notepad++,  that can be used for comparing lists to identify the differences, i.e. which file(s) were not created. The following illustrates how to use Notepad++ for identifying missing file(s) using before and after lists.

1. Open up a Windows Command Prompt and use the DIR command to generate a list of files before and after processing, e.g. list.txt and newlist.txt.
   
   C:/> DIR /b *.las > list.txt
   
2. Run Notepad++. Open up the lists.
   
   
   
3. Select Plugins | Compare | Compare.
   
   
   
   The differences are identified.
   
4. Scroll up or scroll down to see the differences. Or use the scroll buttons.