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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: [eigen] Matrix assignment
- From: Cristóvão Sousa <crisjss@xxxxxxxxx>
- Date: Mon, 20 Oct 2008 18:18:24 +0100
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Hi,
I'm wondering what operator is better for matrix (coefficient wise like)
assignment:
= or << ?
I have a matrixXd "m" which will store the result of some matrices(Xd)
operations.
Matrix "m" should have a fixed size, only known at runtime. If for some reason,
related to a bug in my code, the operations result in a different matrix size,
the assignment
m = "operations with m2,m3,m4,..."
will change "m" size.
I rather need, for debug purposes, an assertion failure being raised.
I discover that the "<<" operator does just what I need (it fails even if the
operations resulting matrix is smaller than "m").
But now I'm wondering if "<<" operator is equal, in terms of speed and laziness
optimizations, to the "=" operator.
So?
Thanks in advance. And thanks very very very much for Eigen! It was the matrix
killer library I was looking for! I had tried Blitz,boost::ublas, GSL, Tvmet,
Newmat...
Honestly, Eigen (version 2) is just the best single piece of C++ code I ever
used!
Cristóvão Sousa
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