Inv not working in mac?

General Usage
2

Determining if a matrix is singular or not is an inherently unstable computation. Different orders of operations of cut-offs on the condition number will give different results.

julia> using AppleAccelerate

julia> A = [1 2 3; 4 5 6; 7 8 9]
3×3 Matrix{Int64}:
 1  2  3
 4  5  6
 7  8  9

julia> using LinearAlgebra

julia> cond(A)   # condition number
5.015946803014265e16
julia> inv(A)    # an unstable approximation to the inverse
3×3 Matrix{Float64}:
  3.15252e15  -6.30504e15   3.15252e15
 -6.30504e15   1.26101e16  -6.30504e15
  3.15252e15  -6.30504e15   3.15252e15

julia> versioninfo()
Julia Version 1.10.2
Commit bd47eca2c8a (2024-03-01 10:14 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: macOS (arm64-apple-darwin22.4.0)
  CPU: 8 × Apple M1 Pro
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-15.0.7 (ORCJIT, apple-m1)
Threads: 6 default, 0 interactive, 3 GC (on 6 virtual cores)
Environment:
  JULIA_EDITOR = code

This matrix is singular in theory but not computationally singular in the tolerances used here.

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