f(x).subs() substitution in sympy (python)
<p>I defined symbols a and f. I'm expecting to use "a(3).subs(a,f)" to get f(3), but instead I got a(3). What's wrong with it?</p>

<pre><code>a, f = symbols('a f')

a(3).subs(a,f)
</code></pre>

<p>You've defined <code>f</code> as a function and then you replaced it with the return value from <code>symbols()</code>.</p>

python sympy