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[dekontrol]

Hi to all and excuse me for the stupid question...

I'm writing a program that should be create one function from another function.

the function "lw(w)" should be obtained from the function "lz(z)",
with the sobstitution of z=(1+w)/(1-w)

So, i write this:

lz((1+w)/(1-w))?lw(w)

but in lw(w) i don't see the result of the calc, but this:

: lw(w)
: lz((1+w)/(1-w))

this, for many reasons, don't is good... i need that lw(w) contain the evalutated expression.

For example, if lz(z) is simply = z, lw(w) should be:
: lw(w)
: (1+w)/(1-w)


Any suggestion?
Please help me
Many thanks!