Thread Subject: Replacing all values in a matrix with values from a lookup table

I need to replace all the values within a 401x410 matrix with values from a lookup table, the lookup table contains normalized values for more than 16,000 gray-scale luminance levels from a previous monitor calibration. I'm currently using a loop going through each cell one at a time but it is horrendously slow and was curious if there are any faster ways to perform this task.

Dear Denton!

> I need to replace all the values within a 401x410 matrix with values from a lookup table, the lookup table contains normalized values for more than 16,000 gray-scale luminance levels from a previous monitor calibration. I'm currently using a loop going through each cell one at a time but it is horrendously slow and was curious if there are any faster ways to perform this task.

Can you please show some example values, e.g. a 3x3 matrix and a corresponding lookup table? If you have integer values (or can convert them to integers), the lookup-table can be applied straight forward, e.g. as in IND2RGB.

Jan