error "undefined function or variable"?

I have run a algarism for a while without problem but recentally it always five me a error:

>> Algorithm_12_21_14_SI_Fix_Diagonal_Change_Fix_test
Undefined function or variable 'mov_avg_JHD'.
Error in
Algorithm_12_21_14_SI_Fix_Diagonal_Change_Fix_test (line
140)
DiffMA=rot90(mov_avg_JHD(Diff,6),3);

But I have a seperate file defined mov_avg_JHD in the same folder and for some reason it dese not recoganize or read it.

Need your help!!!

[Ameer Hamza]

Is the file placed in the current folder?

[Adam Danz]

If you added the mov_avg_JHD file after staring Matlab or after adding the path to its folder, you will have to add the path again using addpath().

Also, check for typos. Function names are case sensitive.

I realize that you ran the Algorithm_12_21_14_SI_Fix_Diagonal_Change_Fix_test function previously without error but if the mov_avg_JHD file was added, move, or renamed, it would cause this error.