4.15: Common Mistakes and Best Practices

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Page ID: 136633

Zara Noroozi
Irvine Valley College

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Mistake	How to Fix
Mixing up row and column order	Remember that MATLAB uses matrix(row, column), not matrix(column, row).
Forgetting the dot in array operations	Use .*, ./, and .^ when you want element-by-element operations
Trying to delete one element from a matrix	You can delete an entire row or column, but not a single middle element of a 2D array
Expecting max(A) to return one number	For a matrix, max(A) returns the maximum value in each column. Use max(A(:)) for the entire matrix.
Reshaping with the wrong number of elements	The new matrix must have the same total number of elements as the original array.
Forgetting that MATLAB flattens column-wise	A(:) reads down columns, not across rows

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