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Re: Applying function to vector by index
From: |
Andy Adler |
Subject: |
Re: Applying function to vector by index |
Date: |
Thu, 12 Dec 2002 14:10:14 -0500 (EST) |
On Thu, 12 Dec 2002, Paul Kienzle wrote:
>
> Personally I would rather not have functions spontaneously converting
> sparse matrices to full since really small sparse matrices can form
> really big full matrices, but I also would not want to introduce
> needless incompatibilities.
>
Converting to full can save memory. Consider your cos(sparse) example.
It takes less memory to encode it as full than in a big sparse (BS)
matrix.
> BTW, I notice that
> sparse(1,1,0)
> returns the following:
> Compressed Column Sparse (rows=1, cols=1, nnz=1)
> (1 , 1) -> 0
> and
> [i,j,v] = spfind(sparse(1,1,0))
> returns
> i = 1
> j = 1
> v = 0
I have code which goes through the matrices generated to
remove zeros introduces this (and in other subtle) ways.
I guess I forgot to apply it in this case.
My current opinion is that I'll try to stay Matlab compatible
unless it is really non-sensical.
Andy
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- Re: Applying function to vector by index, (continued)
- Re: Applying function to vector by index, Paul Kienzle, 2002/12/09
- Re: Applying function to vector by index, Iago Mosqueira, 2002/12/09
- Re: Applying function to vector by index, Paul Kienzle, 2002/12/09
- Re: Applying function to vector by index, Paul Kienzle, 2002/12/09
- Re: Applying function to vector by index, Andy Adler, 2002/12/09
- Re: Applying function to vector by index, Schloegl Alois, 2002/12/10
- Re: Applying function to vector by index, Paul Kienzle, 2002/12/12
- Re: Applying function to vector by index, Andy Adler, 2002/12/12
- Re: Applying function to vector by index, Schloegl Alois, 2002/12/12
- Re: Applying function to vector by index, Paul Kienzle, 2002/12/12
- Re: Applying function to vector by index,
Andy Adler <=
- Re: Applying function to vector by index, Paul Kienzle, 2002/12/12
- Re: Applying function to vector by index, Andy Adler, 2002/12/11
- Re: Applying function to vector by index, Mike Miller, 2002/12/09