arcgis-desktopraster-calculatorspatial-analystzonal statistics
I want the count of the number of raster pixels within that polygon. I ran the Zonal Statistics as Table tool using one polygon as the feature zone data and only getting the SUM. I thought it would be the sum but i had done some rough calculations another way and got the number in the COUNT field.
Can someone explain what the difference between Count and Sum are?
You need to use the %Name% inline variable for your output table names
QGIS first makes an initial pass, checking to see if the center of each raster cell is within the polygon. If fewer than two cell centers are within the polygon, it performs a vector-based intersection for all intersecting cells, whether their center is within the polygon or not, and computes a weight that is the fraction of each cell that is covered by the polygon. If two or more cell centers are within the polygon, those cells are assigned a weight of 1 and all other cells are assigned a weight of 0.
How these weights are applied depends on the statistic in question.
Relevant source code:
Best Answer
What you are looking for is COUNT, which is the frequency of the cells that you processed through Zonal Statistics. Sum, on the other hand, is the sum of cell values covered by your polygon. Overly simplistically, say, your cell values are 2,1,3,4,4 in this case COUNT is 5 and SUM is 14.