Hello list,
I am experimenting with the changevar command. I'm trying to
find out if i can also make it work for s-dimensional integration.
In one dimension, things are simple. We can for example do:
depends(f, x)$
'integrate(f(x), x, 0, 2);
changevar(%, y-x/2, y, x);
Which changes
2
/
[
(%i2) I f(x) dx
]
/
0
into
1
/
[
(%o3) 2 I f(2 y) dy
]
/
0
But can a similar thing be done for s-dimensional integrals too?
Take for example the function:
s: 3;
f(x) := product(x[i], i, 1, s);
Then I have found that I can integrate it using
integrate(integrate(integrate(f(x), x[1], 0, 2), x[2], 0, 2), x[3], 0, 2);
My first question is if the above command can be written shorter and for
more general (maybe even unspecified, sumbolic?) s (suppose you want to play
with the s-value, how would you change the integrate command?).
My second question is then how to apply the variable transformation
y = x/2
for each of the variables and see the transformed expression for the integral?
Thanks for your advice,
Bart
--
"Share what you know. Learn what you don't."