Hello, I found that multiplying a matrix by its inverse does not yield an identity matrix. Please see below a MWE: matrix = [5.93419 4.8067; 4.8067 5.93419] invmatrix = inv(matrix) matrix*invmatrix The last line generates the following output: 2×2 Matrix{Float64}: 1.0 4.44089e-16 4.4…

It’s nearly symmetric. Because of the imprecision inherent in floating point numbers , it’s best to use approximate comparisons like this: julia> varc ≈ varc' true The approximate equality symbol can be typed in the REPL with \approx<TAB>, or you can use the equivalent function call: isapprox(varc,…

Thanks! That solves the previous MWE, but does not solve the issue I am having. Please see below a new MWE with the method you suggested: using Printf Base.show(io::IO, f::Float64) = @printf(io, "%.4f", f) Σzz = [5.9342 5.3408 4.8067 4.3260; 5.3408 5.9342 5.3408 4.8067; 4.8067 5.3408 5.9342…

[image] mengxiaoliu: make the off-diagonal elements zero instead of some value that is very close to zero? You can zero them out manually, eg as in M = matrix*invmatrix; M[abs.(M) .≤ 1e-10] .= 0; M but this is hard to do in a disciplined manner in general.

Matrix multiplied by inverse matrix does not reproduce identity matrix

General Usage

rafael.guerra August 3, 2021, 12:58am 2

One solution is posted here, for display purposes.

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Matrix multiplied by inverse matrix does not reproduce identity matrix

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