When I import data from a text file into IDL and uses it, then the data from the last line in the text file ends up giving errors. So there is some kind of end of file thing going on, that makes reading that last line of data go wrong. I however can't see what is wrong, because when I get my script to show me the numbers from that line, they look as they should, but when I try to use them in calculations or put my data through filters, they don't acts as the number shown. I am using one of two scripts for the read-ins of the files; a professional script from NASA -readpds- and a colleagues script, and both have given me the same type of problems on different files; while other people don't have problems with them, I am assuming since that would quickly have been discovered. I wonder if it can be something to do with that I am using a Mac (I work on IDL 8.2.0 on a Mac IOS 10.8.5.), as that have cause problems one time before with a different script. That time I had however made the text file myself on the mac, while now I am using a data file from NASA, which the readpds was made to read. Do anyone knows how what can be wrong and ways to fix it? I am also having the weird problem with the same file, that when I write less than (LT) a certain number, then the data shown includes that number, just as if I wrote LE. I have used LT and LE hundreds of times, but never before have I had this problem. It can be seen here: print, n_elements(where(a le 0.1)) 64 print, n_elements(where(a lt 0.1)) 64 print, n_elements(where(a lt 0.099999)) 55 The numbers in the array looks in the text file like 0.16 and are in the array shown as 0.16000000. But that don't explain why 0.10000000 < 0.1. Can anyone explain to me what is wrong? I would like to trust my calculations and results that I get from this, but it is hard when I find such obvious errors.