findsym - Determine variables in symbolic expression or matrix
Syntax
findsym(S)
findsym(S,n)
Description
findsym(S) for a symbolic expression or
matrix S, returns all symbolic variables in S in
lexicographical order, separated by commas. If S does
not contain any variables, findsym returns an empty
string.
findsym(S,n) returns the n variables
alphabetically closest to x:
The variables are sorted by the first letters in
their names. The ordering is x y w z v u ... a
X Y W Z V U ... A. The name of a symbolic variable
cannot begin with a number.
For all subsequent letters the ordering is alphabetical,
with all uppercase letters having precedence over lowercase: 0 1 ... 9 A B ... Z a b ...z.
Note
findsym(S) can return variables in different
order than findsym(S,n). |
Examples
syms a x y z t X1 x2 xa xb
findsym(sin(pi*t))
ans =
t
findsym(x+i*y-j*z)
ans =
x,y,z
findsym(a+y,1)
ans =
y
findsym(X1 + x2 + xa + xb)
ans =
X1,x2,xa,xb
findsym(X1 + x2 + xa + xb,4)
ans =
x2,xa,xb,X1
See Also
compose, diff, int, limit, symvar, taylor
 | feval (mupadengine) | | finverse (sym) |  |
Includes the most popular MATLAB recorded presentations with Q&A sessions led by MATLAB experts.
Get the Interactive Kit
Store 
