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Parent: MorphoOptimizationProject
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=== Creating shape manipulation functions ===
See MorphoOptimizationProject_Manipulating_MRIS_et_al
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mris_fix_topology has a hot loop, which does unnecessary calculations of the face normals

mrisComputeOptimalRetessellation and mrisComputeRandomRetessellation have a similar structure

_:_: then it loops over a set of patches, or iterates on one patch. For each patch it calls

_:_:_: mrisDefectPatchFitness, which calls

_:_:_:_: mrisComputeDefectLogLikelihood, which calls

_:_:_:_:_: mrisComputeDefectMRILogUnlikelihood, which

_:_:_:_:_:_: does an expensive computation all the face normals for ALL the faces

_:_:_:_:_:_: does two other expensive steps, which only use a few of the face normals

To simplify, the original code does this

_: loop

_:_: for all fno normal[fno] = f (inputs)

_:_: for a few fno use normal[fno]

_:_: change some inputs

_: end loop

_: change some inputs

_: use some normal[fno]

Since only a few of the face normals are used, it is a waste of time to calculate all of them every time around the loop!

This is replaced by code that does

 . loop
  . for all fno __normal[fno].deferred = true__
  for a few fno __if normal[fno].deferred normal[fno] = f (inputs); normal[fno].deferred = false__ change some inputs
 end loop
 __for a few fno if normal[fno].deferred normal[fno] = f (inputs); normal[fno].deferred = false__ change some inputs use some normal[fno]
See MorphoOptimizationProject_Deferring_calculations

Parent: MorphoOptimizationProject

A variety of techniques have been used.

Creating shape manipulation functions

See MorphoOptimizationProject_Manipulating_MRIS_et_al

Deferring calculations until needed

See MorphoOptimizationProject_Deferring_calculations

MorphoOptimizationProject_BetterSerialCode_DeferCalculations (last edited 2021-09-22 09:46:34 by DevaniCordero)