gdal_calc.py SyntaxError

Question

I tried to use gdal_calc.py to avoid using the manual GUI raster calculator in QGIS. However, I'm not yet familiar with it and having errors with my code:

gdal_calc.py -A perennials.tif -B annuals.tif --outfile=annuals_only.tif --calc="(A<=85 or B=2001)*(A)" --format=GTiff 0 .. evaluation of calculation (A<=85 or B=2001)*(A) 
evaluation of calculation (A<=85 or B=2001)*(A) failed Traceback (most recent call last):
 File "/usr/bin/gdal_calc.py", line 401, in <module>
 main()
 File "/usr/bin/gdal_calc.py", line 394, in main
 doit(opts, args)
 File "/usr/bin/gdal_calc.py", line 288, in doit
 myResult = eval(opts.calc, global_namespace, local_namespace)
 File "<string>", line 1
 (A<=85 or B=2001)*(A)
 ^
SyntaxError: invalid syntax

Is there some thing I can improve in my --calc formula?

Answer 1

Your syntax is wrong for logical operator (or). Try this:

gdal_calc.py -A perennials.tif -B annuals.tif --outfile=annuals_only.tif --calc="A*logical_or(A<=85, B=2001)"

I would also add --NoDataValue=0 to avoid large black areas in the output.

• brentiemapper: Hello, I'm having these errors: 0 .. evaluation of calculation A*logical_or(A<=85, B=2001) failed Traceback (most recent call last): File "/usr/bin/gdal_calc.py", line 401, in <module> main() File "/usr/bin/gdal_calc.py", line 394, in main doit(opts, args) File "/usr/bin/gdal_calc.py", line 288, in doit myResult = eval(opts.calc, global_namespace, local_namespace) File "<string>", line 1, in <module> ValueError: invalid number of arguments
• Zoltan: Please remove the extra characters at the end of your original command or copy/paste the command from my answer.
• brentiemapper: Hello, I did your suggestion. I'm thinking, is it possible that I have problems with numpy? Installed it recently and nothing happens.
• Zoltan: Try to start Python and import numpy manually. Do you use Windows or Linux?
• brentiemapper: I use Linux. Yes I'll try doing it manually.