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Bug 663

Summary: Permit NoChange in setZero, setOnes, setConstant, setRandom
Product: Eigen Reporter: Rhys Ulerich <rhys.ulerich>
Component: Core - generalAssignee: Nobody <eigen.nobody>
Status: CONFIRMED ---    
Severity: enhancement CC: gael.guennebaud, jacob.benoit.1, pw_eigen
Priority: Normal Keywords: JuniorJob
Version: unspecified   
Hardware: All   
OS: All   
Bug Depends on:    
Bug Blocks: 814    
Description Flags
Patch for Bug 663 none

Description Rhys Ulerich 2013-09-25 18:50:21 UTC
If feasible, please consider permitting NoChange as an argument in either the rows or cols slots within the following methods:

x.setZero(rows, cols);
x.setOnes(rows, cols);
x.setConstant(rows, cols, value);
x.setRandom(rows, cols);

That is, the LHS and RHS of the following equalities would behave identically:

x.setZero(NoChange, cols) "==" x.setZero(x.rows(), cols)
x.setZero(rows, NoChange) "==" x.setZero(rows, x.cols())

x.setOnes(NoChange, cols) "==" x.setOnes(x.rows(), cols)
x.setOnes(rows, NoChange) "==" x.setOnes(rows, x.cols())

x.setConstant(NoChange, cols, value) "==" x.setConstant(x.rows(), cols, value)
x.setConstant(rows, NoChange, value) "==" x.setConstant(rows, x.cols(), value)

x.setRandom(NoChange, cols) "==" x.setRandom(x.rows(), cols)
x.setRandom(rows, NoChange) "==" x.setRandom(rows, x.cols())

These would be handy when "x" is complicated to express.  Feel free to close as irrelevant if I'm missing some portion of the API that handles this succinctly.
Comment 1 Gael Guennebaud 2013-10-28 17:27:46 UTC
This should not be difficult to add, and a welcome addition for consistency.  Patch welcome.

In the meantime you can do:

X.resize(NoChange, cols); X.setConstant(2);

which is not much more verbose.
Comment 2 Gael Guennebaud 2016-01-31 13:08:15 UTC
Not critical, but good junior-job. So let's keep it for newcomers.
Comment 3 Philipp Wissmann 2016-03-11 15:43:21 UTC
Created attachment 666 [details]
Patch for Bug 663

I've added support for NoChange in the functions mentioned above.

Please have a look at it.

Comment 4 Nobody 2019-12-04 12:38:31 UTC
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