Summing pixel values from several raster layers with partial overlap in QGIS?
I have several presence maps (rasters values 1 and 0) from different species. They are all from South America, but they do not have the same extend (i.e., different sizes). So, I am trying to develop a...
View ArticleConditional statement in ArcGIS Raster Calculator?
I am new to Arcmap… I want to make a conditional statement in Raster calculator that checks if the pixel does not contain water or forest value ,, assign them snow as 1 and vice versa… Like the...
View ArticleHow to change value in raster layer?
I have created future temperature raster (tiff format) in ArcGIS. However I want all pixel’s value to be multiply with 10 (constant value). I tried to use con tool and raster calculator in spatial...
View ArticleAdding all Binary Rasters in a Directory Using Raster Calculator in a...
I have a directory with binary raster files (1 band only) which I need to add in a standalone python script. The problem is the rasters have different number of rows and columns and different...
View Articleproblem with raster calculator results when subtracting two rasters with...
I have two elevation datasets which I am trying to subtract to calculate thickness (using ArcGIS raster calculator). The first datset is a tif which is oriented north-south and has a cell size of 5 ft...
View ArticleMarkov chains, cellular automata, and raster algebra
I need to build a probabilistic cellular automaton for simulating land-use changes and am wondering how to implement this in a GIS. I understand that Markov chains are a way of doing this, and IDRISI...
View Articleunexpected output from raster calculator function
Working in ArcMap, I am trying to convert the logit values in raster into their actual probabilities (logistic regression,) using the following function: 1/(1+Exp(-”sn_topo_poly_log”)) Ive used this...
View ArticleArcMap raster calculator error 000539
Using ArcMap 10.3, I am trying to perform map algebra on a raster with 2013 annual PRISM precipitation for the U.S. (http://prism.oregonstate.edu/recent/). The raster has 1 band an is floating point....
View ArticleRaster calculator fails with large raster in QGIS
I’m working in QGIS 2.14.1 with a DEM ranging from 200 feet to 1600 feet elevation called “dem_3m_Zft1b” (geotiff, 16822 X 33349 cells, No-data =-9999) If I enter "dem_3m_Zft1b" > 0 in the raster...
View ArticleCreate Cost Surface Raster with slope as percentage of total costs
I know there is a similar question on this website (How to Create Cost Surface Raster for Least Cost Path Analysis?) , but I couldn’t find the answer that I’m looking for. I’m currently working with a...
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