error in matrix creation options

[williamstein]

> After trying some things, I've noticed that it is possible to coerce a
> flat list into a sparse matrix but not a list of lists.
> 
> E.G.
> sage: B = MatrixSpace(ZZ,5,5)
> sage: v = [0 for i in range(25)]
> sage: u = [[0 for i in range(5)] for j in range(5)]
> sage: B(v)
> [0 0 0 0 0]
> [0 0 0 0 0]
> [0 0 0 0 0]
> [0 0 0 0 0]
> [0 0 0 0 0]
> 
> sage: B(u) ---> results in the same error as before.
> Is there a conceptual reason that a flat list works, but a list of

That looks like just a mistake on our paper.  We should make
it so both cases work. 

Component: linear algebra

Issue created by migration from https://trac.sagemath.org/ticket/352

[sagetrac-mabshoff]

comment:1

This work since at least Sage 2.8.1

----------------------------------------------------------------------
| SAGE Version 2.8.1, Release Date: 2007-08-18                       |
| Type notebook() for the GUI, and license() for information.        |
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sage: B = MatrixSpace(ZZ,5,5)
sage: v = [0 for i in range(25)]
sage: u = [[0 for i in range(5)] for j in range(5)]
sage: B(u)

[0 0 0 0 0]
[0 0 0 0 0]
[0 0 0 0 0]
[0 0 0 0 0]
[0 0 0 0 0]
sage: B(v)

[0 0 0 0 0]
[0 0 0 0 0]
[0 0 0 0 0]
[0 0 0 0 0]
[0 0 0 0 0]