The "str2double" function eliminates all commas from the input string before attempting to determine its numeric value. The "str2double" function does not have the ability to recognize misplaced commas or commas that are used as decimal separators.
As a workaround, you can replace the commas with periods prior to calling str2double:
str2double(strrep('4,01',',','.'));
Alternatively, if using character arrays, you can create your own MATLAB function that converts a string to a numeric value.
For example, if you would like to treat the comma as a decimal point and periods as the thousands separator, you can do the following, where "s" is the number to convert:
periods = (s == '.');
commas = (s == ',');
s(commas) = '.';
s(periods) = [];
str2double(s);
