Hello,
I have a question about how maxima handles function definitions and
derivatives. I am mainly interested in plotting functions associated
with other functions
For instance, consider the following lines.
(%i1) f(x):= x^2;
2
(%o1) f(x) := x
(%i2) g(x):= diff(f(x),x);
(%o2) g(x) := diff(f(x), x)
(%i3) g(2);
Non-variable 2nd argument to diff:
2
#0: g(x=2)
-- an error. To debug this try debugmode(true);
(%i4) g(t):= subst(x=t,diff(f(x),x));
(%o4) g(t) := subst(x = t, diff(f(x), x))
(%i5) g(t);
(%o5) 2 t
(%i6) g(x);
(%o6) 2 x
(%i7) g(2);
(%o7) 4
Why is it necessary to put in the 'subst' command? Is there a better
way to do this?
TIA,
-sen
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