Polynomials over number fields

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So this method only computes determinants? Is there an easy way to manually iterate over submatrices?

You can take submatrices using indices

sage: m = matrix(4, range(16))
sage: m
[ 0  1  2  3]
[ 4  5  6  7]
[ 8  9 10 11]
[12 13 14 15]
sage: m[1:3, 2:4]
[ 6  7]
[10 11]

(be careful indices starts at 0)

The error also shows for the one $4$-minor of a random $4\times 4$-matrix over R,

var('x')
K.<s,t> = NumberField([x^2-2,x^2-5])
R.<p0,p1,p2,p3,p4,p5> = K[]
M = Mat(R,4,4).random_element()
try:
    mins = M.minors(4)
except TypeError:
    print "...got TypeError"

This may be relevant for the tests to fix the bug.

I tried to change the base from R to its fraction field, got no error, but also had no time to wait for that one determinant computation...

@dan_fulea The determinant code has special cases for size 2 and 3 reason why you do not see the bug before size 4.

Yes, thanks, my intention was just to give a simple instance for the error, that may serve as test case for the opened ticket... (And also to mention that the 4x4 determinant of the random matrix could not be computed in real time, so computing all 7x7 minors of a 10x10 random matrix...)