Conditional statement in gdal_calc with result as float, not boolean

Question

Many examples on gis.se that refer to gdal_calc give a boolean example. example 1 example 2

If I need to calculate a conditional statement on a float:

If Raster_Value >= 1024, then 1024; else Raster_Value.

How do I perform that operation in the gdal raster calculator command line

EDIT I tried radouxju answer and it worked, except for the cell values that didn't. here are 3 kinds of results I got

Here is the tool gui and the parameters I've entered

radouxju · Accepted Answer · 2015-12-10 11:37:28Z

5

you can define the output type using the "type" option

--type=TYPE output datatype, must be one of ['Int32', 'Int16', 'Float64', 'UInt16', 'Byte', 'UInt32', 'Float32']

so it would look like this

gdal_calc.py -A yourInput.tif --outfile=yourOutput.tif --calc="1024*(A>=1024)+A*(A<1024)" --NoDataValue=0 --type='Float32'

answered Dec 10, 2015 at 11:37

radouxju

49.9k2 gold badges71 silver badges144 bronze badges

Well, that seemed to work, apart from the fact that certain cells below threshold were changed too. i68.tinypic.com/10pxcig.png
– HDunn
Commented Dec 10, 2015 at 11:52
this is strange. Do you also have unexplained results with Float64 ?
– radouxju
Commented Dec 10, 2015 at 13:42
I have a similar question, so, how can I change the pixel value to entire raster? In SAGA GIS it's simple: ifelse (a=0,1,a). How to do this via gdal_calc.py?
– Jorge Santos
Commented Feb 8, 2018 at 14:20
2

I would use "--calc="(a==0)*(1)+(A!=0)*(A)"
– gonzalez.ivan90
Commented Nov 6, 2019 at 3:58

Add a comment |

1 Answer 1