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Kernels of matrices over integral domains are broken #8072

Open 1d7ec08f-60ae-4512-91a6-8324c06eab9f opened 14 years ago

1d7ec08f-60ae-4512-91a6-8324c06eab9f commented 14 years ago

Asking for a kernel of a matrix over an integral domain has a dedicated chunk of code that tries to create a submodule as a return value. Only there is no support for submodules over domains (just PIDs and fields).

I'll be going after this as part of a larger overhaul of matrix kernels generally.

sage: R=ZZ['x']
sage: R.is_integral_domain()
True
sage: W=R^2
sage: W
Ambient free module of rank 2 over the integral domain Univariate Polynomial Ring in x over Integer Ring
sage: A=matrix(R,[1,2,3])
sage: A.right_kernel()
<snip>

/sage/dev/local/lib/python2.6/site-packages/sage/matrix/matrix2.so in sage.matrix.matrix2.Matrix.right_kernel (sage/matrix/matrix2.c:13840)()

AttributeError: 'FreeModule_ambient_domain' object has no attribute 'submodule'

CC: @jasongrout

Component: linear algebra

Issue created by migration from https://trac.sagemath.org/ticket/8072

jasongrout commented 14 years ago
comment:1

Feel free to CC me on any linear algebra tickets.