strncmpi
strncmpi(str1,str2,n) returns true if the n first characters of string str1 are the same in str2.
Comparison is case insensitive.
Examples
> strncmpi('abc','abd',2)
[ans:true]
> strncmpi('abc','Abd',2)
[ans:true]
> strncmpi('abc','abd',3)
[ans:false]