MATLAB: Sym2cell not working even for the example given in document.symbolicsyms x y S = [x 2 3 4; y 6 7 8; 9 10 11 12]S =[ x, 2, 3, 4] [ y, 6, 7, 8] [ 9, 10, 11, 12]c=sym2cell(S) Undefined function 'sym2cell' for input arguments of type 'sym'. Best AnswerAccording to the note at the bottom of the documentation page this function was introduced in release R2016a. I suspect you're using an earlier release of Symbolic Math Toolbox. Related QuestionError using symengine Unable to convert expression into double array.I want to use atan2 in the equation. When I use atan2 , I get answer NaN. But when I use ‘atan’ , i didn’t get NaN. WhyIndex exceeds the number of array elements (1).