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I would like to know the area that each value in a raster has... The raster I have has values from 2-15 and I would like to know the area that each value is occupaying within my polygon... Thanks!

I vectorized and calculated the area using geometry columns but I find a problem when I add all of the calculated segments, they don't match the poligon's total area!

The fist picture is the resulting raster, I clipped my polygone out and then vectorized it (pic of de right)...

enter image description here

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a sample of the erroneous result (print screen or something similar) would help a lot. Also are you performing your calculations in a valid CRS? WSG84 (epsg:4326) is not a very good choice because by definition the measurements are in degrees. –  nickves Apr 9 '13 at 18:24
    
I am using UTM :) –  Nadia Apr 9 '13 at 19:15
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you said the error is in the area measurements. we'll need to see them. –  underdark Apr 9 '13 at 20:13
    
Yes, well tha's been analyzed using excel but I will try a couple of solutions I saw in other question responses –  Nadia Apr 9 '13 at 20:29
    
Can you post the differences in area? How did you get the total area in the raster btw? –  R.K. Apr 10 '13 at 13:52
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