Find symbols in expression and return them as a symbolic vector.
The symbols are sorted in alphabetic order with capital letters
first. If n is specified, the n symbols closest to
x are returned.
Example:
syms x y f = x^2 + 3*x*y - y^2; symvar (f) ⇒ (sym) [x y] (1×2 matrix) symvar (f, 1) ⇒ (sym) x
Further examples:
syms a x t f = a*x + t; symvar (f, 1) ⇒ (sym) x symvar (f, 2) ⇒ (sym) [x t] (1×2 matrix) symvar (f, 3) ⇒ (sym) [x t a] (1×3 matrix)
And note its ok to ask for more:
symvar (f, 1000) ⇒ (sym) [x t a] (1×3 matrix)
Compatibility with other implementations: the output should match the order of the equivalent command in the Matlab Symbolic Toolbox version 2014a, as documented here: http://www.mathworks.co.uk/help/symbolic/symvar.html
If two variables have the same symbol but different assumptions, they will both appear in the output. It is not well-defined in what order they appear.
See also: findsymbols, @sym/findsym.
Package: symbolic