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Symbolic Variables, Expressions, Functions, and Preferences

Create symbolic variables, expressions, functions, and set preferences

Symbolic Math Toolbox™ introduces a special data type — symbolic objects. This data type includes symbolic numbers, symbolic variables, symbolic expressions, and symbolic functions. It also includes vectors, matrices, and multidimensional arrays of symbolic numbers, variables, expressions, and functions. Using symbolic objects in computations indicates that MATLAB® must perform these computations analytically instead of numerically. Symbolic computations are exact and are not prone to round-off errors. For more details about symbolic objects, see Use Symbolic Objects to Represent Mathematical Objects. For a quick guide on creating symbolic variables, expressions, and functions, see Create Symbolic Numbers, Variables, and Expressions and Create Symbolic Functions.


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symsCreate symbolic scalar variables and functions, and matrix variables and functions
symCreate symbolic variables, expressions, functions, matrices
symfunCreate symbolic functions
symmatrixCreate symbolic matrix variable (Since R2021a)
symmatrix2symConvert symbolic matrix variable to array of scalar variables (Since R2021a)
symfunmatrixCreate symbolic matrix function (Since R2022a)
symfunmatrix2symfunConvert symbolic matrix function to symbolic function (Since R2022a)
str2symEvaluate string representing symbolic expression
foldCombine (fold) vector using function
piecewiseConditionally defined expression or function
symvarFind symbolic variables in symbolic input
argnamesInput variables of symbolic function or matrix function
formulaReturn body of symbolic function or matrix function
hasCheck if expression contains particular subexpression
childrenSubexpressions or terms of symbolic expression
symTypeDetermine type of symbolic object
symFunTypeDetermine functional type of symbolic object
isSymTypeDetermine whether symbolic object is specific type
hasSymTypeDetermine whether symbolic object contains specific type
findSymTypeFind symbolic subobjects of specific type
mapSymTypeApply function to symbolic subobjects of specific type
isfiniteCheck whether symbolic array elements are finite
isinfCheck whether symbolic array elements are infinite
isnanCheck whether symbolic array elements are NaNs
symprefSet symbolic preferences