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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 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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symCreate symbolic variables, expressions, functions, matrices
symsCreate symbolic scalar variables, functions, and matrix variables
symfunCreate symbolic functions
symmatrixCreate symbolic matrix variable
symmatrix2symConvert symbolic matrix variable to array of scalar variables
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
formulaReturn body of symbolic 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


Create Symbolic Numbers, Variables, and Expressions

Use symbolic values and variables.

Create Symbolic Functions

Use symbolic functions that accept symbolic inputs, such as f(x,y).

Create Symbolic Matrices

Use matrices containing symbolic values.

Create Symbolic Matrix Variables

Use symbolic matrix variables.

Symbolic Objects to Represent Mathematical Objects

Use symbolic objects to represent mathematical objects.

Find Symbolic Variables in Expressions, Functions, Matrices

Find variables in symbolic expressions.

Choose syms or sym Function

Choose syms or sym function.

Change Output Display Format of Symbolic Results in the Live Editor

Modify output of symbolic results.

Add Subscripts, Superscripts, and Accents to Symbolic Variables in the Live Editor

Add suffixes to symbolic variables.

Copy and Paste Symbolic Output in Live Editor

Copy and paste symbolic output.