History.xml strange behavior

When MATlab detect an error, after the error message MATLAB display

[1,2,3]*[2,1]'

Error using *

Incorrect dimensions for matrix multiplication. Check that the number of columns in the first matrix

matches the number of rows in the second matrix. To perform elementwise multiplication, use '.*'.

An error was encountered opening file C:\Users\Radu\AppData\Roaming\MathWorks\MATLAB\R2020a\History.xml

An error was encountered opening file C:\Users\Radu\AppData\Roaming\MathWorks\MATLAB\R2020a\History.xml

[Radu Trimbitas]

The last two messages appear systematicaly, after any kind of error.

Answer 1

[Gaurav Garg]

Hey

I wasn't able to reproduce the same issue on my system. I suspect the error would be because of some history files unable to load during MATLAB startup (MATLAb stores all the commands from command history in a file named history.xml), though they don't seem to have any impact on the normal code.

I would recommend you to restart MATLAB, change the number of rows in the second matrix (because matrix multiplication doesn't support your case - columns in first matrix and rows in second matrix should be same) and try the code again.