Custom Query (35 matches)
Results (22 - 24 of 35)
Ticket | Resolution | Summary | Owner | Reporter |
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#22 | fixed | Represent bitmaps as arrays of tuples | ||
Description |
Representing bitmaps as a 3D array isn't ideal because there's no way to perform a map over all the pixels. With this representation:
Suppose we want to convert the image to greyscale in a single operation. We'd really need a function like:
However, that doesn't work because we can't guarantee that the worker function always returns an array of the same length as the original. Because of this we can't guarantee that the result is rectangular, and Repa can only deal with rectangular arrays. If instead we represented Bitmaps as:
Then we could use the original map function and there'd be no problem.
Note that using triples is just as efficient as using a DIM3 array. Repa uses unboxed |
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#23 | fixed | Add array update operator (//) | ||
Description |
From SO: (//) :: Shape sh => Array sh a -> [(sh,a)] -> Array sh a (//) arr us = fromFunction (extent arr) (\sh -> case lookup sh us of Just a -> a Nothing -> index arr sh) |
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#24 | fixed | Unneeded Elt constraint in type of traverse functions | ||
Description |
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