List of matrices bug Algebra

hawe shared this problem 2 years ago

In the other way round regarding

LE={{{1, 0, 0}, {0, 1, 0}, {0, 2, 1}}, {{1, 0, 0}, {-1, 1, 0}, {0, 0, 1}}, {{1, 0, 0}, {0, 1, 0}, {1, 0, 1}}}

invert members of matrix list by

Sequence(2 * Identity(3) - Element(LE, k),k,1,3)

fails in algebra window


seems to stuck on last index

BTW: should not be possible to do the job by

2 * Identity(3) - LE

Comments (5)


Inverting list LE is also different in CAS in AlgebraView

CAS: LE^-1 is correct and AlgebraView LE^-1=undefined

perhaps important LE is defined in CAS


invert(matrix) is the right form, not invert(list) you can do l1 = Zip(Invert(2Identity(3) - m), m, LE)

Zip((2Identity(3) - m)⁻¹, m, LE) works also


We have different handling of LE^-1 in CAS (inverting members of LE) and LE^-1 in AlgebraView (undefined). I also tried Zip, but was not successful in CAS but OK in ALgebraView - shouldn't we have consistent handling?


invert(M) = 2 Identity(n)-M

I do not need both (Elementarmatrices) - even your postet form do not work (5.0.518)...


Product(LE) do not work in CAS - do you see an alternative way (not AlgebraView - is OK there)


there is ever two ways for operations on list: as list or as matrix

this seems change in CAS or algebra view

you can try Product(LE(n),n,1,Length(LE)) in CAS

or Product(element(LE,n),n,1,Length(LE)) if there is problem with short notation

I think there is a bug with the deep of zip of lists in CAS



Thank you, great,

I have not seen, not expected, to use Product in this way - it works, I cannot use short index notation (AlgebraView) because I want to have variables in matrices

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