Can I "y(s):=laplace(y(t),t,s);"?



Hi!

Sadly I'm too ignorant to know if this is a bug.

I want to define a function that involves the laplace transform.

I define a function and check the laplace transform:

(%i1) y(t):=sin(t);
(%o1)                           y(t) := sin(t)
(%i2) y(t);
(%o2)                               sin(t)
(%i3) laplace(y(t),t,s);
                                      1
(%o3)                               ------
                                     2
                                    s  + 1

Everything is fine so far. Then, I define a new function, y(s):


(%i4) y(s):=laplace(y(t),t,s);
(%o4)                     y(s) := laplace(y(t), t, s)

If I try to get y(t) again I get a long error:


(%i5) y(t);
Control stack guard page temporarily disabled: proceed with caution

Maxima encountered a Lisp error:

 Control stack exhausted (no more space for function call frames).
This is probably due to heavily nested or infinitely recursive function
calls, or a tail call that SBCL cannot or has not optimized away.

PROCEED WITH CAUTION.

Automatically continuing.
To reenable the Lisp debugger set *debugger-hook* to nil.
Control stack guard page temporarily disabled: proceed with caution
Maxima encountered a Lisp error:

 Control stack exhausted (no more space for function call frames).
This is probably due to heavily nested or infinitely recursive function
calls, or a tail call that SBCL cannot or has not optimized away.

((This message reapeats 10 or so times))

PROCEED WITH CAUTION.

Automatically continuing.
To reenable the Lisp debugger set *debugger-hook* to nil.
(%i7) y(s);

Unsurprisingly, I get the same error.

Is this behaviour normal? Did I do anything wrong?

Thanks in advance,

Javier


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