passing functions as argument one more time

Thank you Richard

This is the reason I was using apply command as suggested by Barton in an earlier posting

(%i1)  g(f,x):=block([h:f],diff(h(x),x))$

(%i2)  h(t):=t^3 + t$

(%i3)  p(t) := sqrt(5) * t^2$

(%i4)  g(h,x);
                                              2
(%o4)                              3 x  + 1
(%i5)  g(p,x);
                                              2
(%o5)                              3 x  + 1
(%i6)  gg(f,t) := diff(apply('f,[t]),t)$

(%i7)  gg(p,x);
(%o7)                             2 sqrt(5) x
(%i8)  gg(h,t);
                                              2
(%o8)                              3 t  + 1



 Defining functions inside may not be popular and I am not an experienced user of maxima but
I need to pass different functions to compute its B-spline representations.  I  do not want earlier functions to corrupt results.  These are not the actual computations that I am doing.  This is my way of identifying the problem so I can post it.

I now understand how to do my computations.  Thank you for your  input.

Ram
 -------------- Original message ----------------------
From: Richard Fateman <fateman at cs.berkeley.edu>
> 1. try apply(f,[t]). I don't know why you are doing apply('f ...).
> 
> 2. block ([...],local(h), ..h(x):= ....
> 
> 3. defining functions within functions was not a popular way of writing 
> lisp programs in 1968.
> It still isn't, though with scheme and lexically scoped common lisp it 
> is more plausible.
> You seem to be straining to do something that can be done by this:
> 
> ff(f,x):= block([], local(h), h(x):= if x<1 then x else 3*x,   
> apply(f,x)*h(2*x));
> 
> 
> 
> RJF
> 
> 
> amli at comcast.net wrote:
> 
> >1.  How can I make sure that the functions defined in global space do not 
> conflict with passing of 
> >function arguments? For example I do not want f(x) defined outside the program  
> conflict with passing the function f.   (In a scipt file I may have many 
> functions defined)
> >
> >
> >x:5;
> >t:3;
> >ff(f,x):=block([t,g,h],g:apply('f,[t]),if x<1 then h(x):=x else 
> h(x):=3*x,ev(g,t=x)*h(2*x));
> >ff(sin,2);    //works
> >
> >
> >f(x):=x^2;
> >ff(f,x):=block([t,g,h],g:apply('f,[t]),if x<1 then h(x):=x else 
> h(x):=3*x,ev(g,t=x)*h(2*x));
> >ff(sin,2);  //does not work
> >
> >I tried this 
> >(x):=x^2;
> >ff(f,x):=block([t,g,h],g:'apply('f,[t]),if x<1 then h(x):=x else 
> h(x):=3*x,ev(g,t=x)*h(2*x));
> >ff(sin,2);  
> >but how do you get the final evaluation.
> >
> >2.  I also do not want the functions defined inside the program such as h have 
> global scope.  How can I restrict them to be local only.   I suppose I could use 
> the kill command.  Is that the only solution?
> >
> >Thank you
> >
> >Ram
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> >Maxima at math.utexas.edu
> >http://www.math.utexas.edu/mailman/listinfo/maxima
> >  
> >
>