Using IF statements with maths where the input is not an integer
Hi All
I've made a few scripts which using GDAL extract the value of a pixel within a given raster. The purpose is to work out the combine value of every pixel. I thought there may have been an easier way to do this but alas!
The code below extracts the pixel value at position X Y. The value is a floating point rather than an integer and thats where my problem lies. The if statement simply exports the value to a txt file. Other scripts take care of the rest ie change values of X Y and summing the resultant txt files.
However, I get the following message back when ever my statement is true because my value isn't an integer;
extract2.sh: line 4: [: 2.15787172317505: integer expression expected
Please note the raster file mostly contains zero values, and its only the values greater than zero I'm interested in, which is why I added the expression.
Any ideas how I can alter this code so the IF statement excepts integers? Alternatively if anyone knows of a faster method of quickly summing the values of a raster file, that would be equally useful.
Many thanks in advance for any assistance you can offer.
Andy
Last edited by vbe; 08-12-2011 at 09:50 AM..
Reason: please use code tags!
Whilst re-examining what I'm trying to do I've realised that I may be over complicating things, I can turn my original raster file into a ascii txt file with one command. So now all I need to do is work out how to sum all the values within a txt file.... I am sure there must be a post on that around here somewhere!
More practice at shell scripting anyway!
---------- Post updated at 02:39 PM ---------- Previous update was at 01:50 PM ----------
Ok maybe this is harder than I thought it might be. It seems its not easy to sum up floating point values in a txt file as many programs are designed for use with integers.
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