Enhanced Laplace transforms and desolve for Maxima



Mark H Weaver <mhw at netris.org> wrote on 01/24/2011 12:18:36 PM:

> > My preference would be to *delete* the function unit_step_mult_simp
> > from abs_integrate.
> 
> Agreed.  I will rewrite the new version in lisp, and make it part of the
> new step function code I'm working on.

Super--the next time I do abs_integrate maintenance, I'll delete
unit_step_mult_simp. 

> I'm not sure what you mean by "derivative divides integration for
> hstep".  Do you mean cases where you can change the variable of
> integration, e.g. u=hstep(x)? 

Derivative divides integration is also known as integration by 
subsitution:
integrate(2 * x * f(x^2),x) --> subst(z = x^2, integrate(f(z),z)) --> ...

There is a symbol property mechanism (I think) for telling Maxima 
the antiderivative of a function.

If I were to declare a do-over for abs_integrate, maybe I'd convert signum 
&
friends to conditionals and then integrate the conditionals.

Thanks,

--bw