Find the inverse of a Matrix in MATLAB, is inv(A) or A\eye(size(A)) more precise? -


this question has answer here:

the title explains already. if need find inverse of matrix, there reason should use a\eye(size(a)) instead of inv(a)? , before ask: yes, need inverse, not calculations.

ps: 

isequal(inv(a), a\eye(size(a))) ans =  0

so 1 more precise?

update: question closed appeard duplicate of question "why inv in matlab slow , inaccurate". question here differs not addressing speed, nor accuarcy of function inv difference of inv , .\eye calculate true inverse of matrix.

if need inverse, should use inv.

the inverse calculated via lu decomposition, whereas backslash operator mldivide calculates solution linear system using different methods depending on properties of matrix a (see https://scicomp.stackexchange.com/a/1004), can yield less accurate results inverse.

it should noted if want solve linear system, calculation going faster , more accurate using mldivide(\). matlab documentation of inv 1 big warning not use inv solve linear systems.


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