sympy: test subexpression for trig function -

i trying test whether sub-expression contains sin function (or trig function)

from sympy import sin, symbols, wild a, b, x, y = symbols('a, b, x, y') w1=wild('w1')

i can this:

>> (a*sin(x)+b*sin(y)).has(sin(x)) out: true

but not work:

>>: (a*sin(x)+b*sin(y)).has(sin(w1)) out: false

how test 1 or more sin functions regardless of argument?

if want use wilds, use find:

in [11]: (a*sin(x)+b*sin(y)).find(sin(w1)) out[11]: set([sin(x), sin(y)])

but if searching single function sin, , not generic expressions, easier , faster way use atoms:

in [12]: (a*sin(x)+b*sin(y)).atoms(sin) out[12]: set([sin(x), sin(y)])

if want check multiple trig functions, atoms takes multiple arguments, more efficient calling multiple times

in [14]: (a*sin(x)+b*cos(y)).atoms(sin, cos) out[14]: set([sin(x), cos(y)])

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