MATLAB: Find index for mx1 cell with specific string

find index for mx1 cell with specific string

I have a mx1 cell in A table as Scenario column. I want to find the index matching the string 'Scenario #' using following:

Scenario_list=A.Scenario(Scenario==['Scenario 20']);

Received a "Error using == Matrix dimensions must agree." error message.

Best Answer

For comparing a cell array of char vectors and a char vector you have to use strcmp, or strcmpi, or strncmp, etc:

idx = strcmp(A.Scenario,'Scenario 20')

The == operator only works for string arrays:

https://www.mathworks.com/help/matlab/matlab_prog/create-string-arrays.html

Do not confuse character vectors or character arrays with string arrays:

https://www.mathworks.com/help/matlab/characters-and-strings.html

Related Solutions

MATLAB: Does STRMATCH in MATLAB cause an error for a cell array containing a numeric value

In this example:

str = 9;
strs = strvcat('This is a string array','with two rows');
ind = strmatch(str,strs);

the normal STRMATCH is used, since the first input is not a cell array. In this case, 9 could be used as an ASCII value, and converted to a tab character. That character can then be compared with the other strings.

In this example:

str ={9};
strs = strvcat('This is a cell array of strings','with two rows');
ind = strmatch(str,strs);

@CELL/STRMATCH will be used, since the first input is a cell array. In this case, the code checks that the cell array contains strings, and converts it to a char array:

if iscellstr(str), str = char(str); end

Cell arrays of strings are special cases of cell arrays, which are commonly used to store strings together which have different lengths, and there are many instances where cell arrays of strings and strings can be used interchangeably. However, {9} is not a cell array of strings, so it is not converted to a character array, which leads to the error being thrown by this code:

if ~ischar(str) | ~ischar(strs)
    error('Requires character array or cell array of strings as inputs.')
end

MATLAB: Multiply mx1 matrix to mxn matrix

% Make up some data
A = rand(4000,1);
B = rand(4000,5662);
C = A.*B; % If you have a recent enough version of MATLAB (R2016b or later)
C = bsxfun(@times,A,B); % If you have an older version

Best Answer

Related Solutions

MATLAB: Does STRMATCH in MATLAB cause an error for a cell array containing a numeric value

MATLAB: Multiply mx1 matrix to mxn matrix

Related Question