9.4.4 List of variables of an algebraic expressions
The
algvar
command finds the symbolic variable names in an expression and orders them.
algvar
takes
expr
, an expression.
algvar(
expr
)
returns the list of the symbolic variable names used in
expr
, ordered by the algebraic extensions required to build
expr
.
Examples
algvar
(
y
+
x
*
sqrt
(
z
))
⎡
⎣
⎡
⎣
y
,
x
⎤
⎦
,
⎡
⎣
z
⎤
⎦
⎤
⎦
algvar
(
y
*
sqrt
(
x
)*
sqrt
(
z
))
⎡
⎢
⎢
⎣
y
z
x
⎤
⎥
⎥
⎦
algvar
(
y
*
sqrt
(
x
*
z
))
⎡
⎣
⎡
⎣
y
⎤
⎦
,
⎡
⎣
x
,
z
⎤
⎦
⎤
⎦
algvar
(
y
+
x
*
sqrt
(
z
)+
y
*
sin
(
x
))
⎡
⎣
⎡
⎣
y
,
x
,
sin
x
⎤
⎦
,
⎡
⎣
z
⎤
⎦
⎤
⎦
