[GRASS-user] Differences Between ERDAS and GRASS About NDVI Statistics

[Gökçen Güner]

Hi,
This will not be a specific GRASS question. My friend and I tried to
calculate NDVIs of same data set and results seem same to us. But checking
statistics of each output we saw that statistics are very different. I
mean, median, mean, std.dev values of Grass output and Erdas output are
different. We couldn't find an explanation for this situation. What can be
the reason for this?

PS:
For NDVI, we used this formula: (NIR_Band - RED_Band) / (NIR_Band +
RED_Band)
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