What is the time and memory cost of reshaping a matrix?
Given a matrix M with N elements, and I reshape to any other
size having N elements, I would hope I'm only changing the
matrix shape parameters rather than *any* memcpy at all.
However I see no post or doc on this. Anyone know?
> What is the time and memory cost of reshaping a matrix?
>
> Given a matrix M with N elements, and I reshape to any other
> size having N elements, I would hope I'm only changing the
> matrix shape parameters rather than *any* memcpy at all.
>
> However I see no post or doc on this. Anyone know?
Run the following:
format debug
a=1:10
b=reshape(a,2,5)
pr has the same value, which means both share the same data block.
Peter Boettcher <boettcher@ll.mit.edu> wrote in message
<muyve27m6bm.fsf@G99-Boettcher.llan.ll.mit.edu>...
> "Jay " <jay.damask@mlp.com> writes:
>
> > What is the time and memory cost of reshaping a matrix?
> >
> > Given a matrix M with N elements, and I reshape to any other
> > size having N elements, I would hope I'm only changing the
> > matrix shape parameters rather than *any* memcpy at all.
> >
> > However I see no post or doc on this. Anyone know?
>
> Run the following:
>
> format debug
> a=1:10
> b=reshape(a,2,5)
>
> pr has the same value, which means both share the same
data block.
>
> -Peter
okay, super. I didn't know about the format debug. Thanks
for the help.
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