How to verify if a row or a column or a cubic 3x3 have a repeated number for sudoku?

Say i got an 9x9 array and want to write a function to check if any row or column or 3x3 cell have a repeat number or not for sudoku. it would return a bolean value depend on the result. Any suggestion? Thank

Answer 1

[Walter Roberson]

Suppose you store NaN for all slots that have not had anything written to them. Then extract the appropriate portion of the array, such as

s = A(4:6, 1:3);

s(isnan(s)) = [];
had_dup = numel(unique(s)) ~= numel(s);

[Dyuman Joshi]

This looks like a copy-paste of a Cody question (#114).This account is fairly new as well. Seems suspicious.

[NSHh]

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