Re: Applying the Integration Function to a List Of
- To: mathgroup at smc.vnet.net
- Subject: [mg88759] Re: [mg88739] Applying the Integration Function to a List Of
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Fri, 16 May 2008 05:29:13 -0400 (EDT)
- Reply-to: hanlonr at cox.net
Simplified version regions = {{{x, 0, a}, {cx, 0, b}, {y, 0, c}, {cy, 0, d}}, {{x, 0, 2 a}, {cx, 0, b}, {y, 0, c}, {cy, 0, d}}, {{x, 0, a}, {cx, 0, 3 b}, {y, 0, c}, {cy, 0, d}}}; Integrate[1, Sequence @@ #] & /@ regions {a b c d,2 a b c d,3 a b c d} Bob Hanlon ---- John Snyder <jsnyder at wi.rr.com> wrote: > Assume that I have already determined a list of 4 dimensional regions as > follows: > > regions={{{x,0,a},{cx,0,a+x},{y,0,Sqrt[a^2-cx^2+2 cx > x-x^2]},{cy,0,Sqrt[a^2-cx^2+2 cx > x-x^2]+y}},{{x,0,a},{cx,0,a+x},{y,Sqrt[a^2-cx^2+2 cx x-x^2],2 > a-Sqrt[a^2-cx^2+2 cx x-x^2]},{cy,-Sqrt[a^2-cx^2+2 cx > x-x^2]+y,Sqrt[a^2-cx^2+2 cx x-x^2]+y}},{{x,0,a},{cx,0,a+x},{y,2 > a-Sqrt[a^2-cx^2+2 cx x-x^2],2 a},{cy,-Sqrt[a^2-cx^2+2 cx x-x^2]+y,2 > a}},{{x,a,2 a},{cx,-a+x,2 a},{y,0,Sqrt[a^2-cx^2+2 cx > x-x^2]},{cy,0,Sqrt[a^2-cx^2+2 cx x-x^2]+y}},{{x,a,2 a},{cx,-a+x,2 > a},{y,Sqrt[a^2-cx^2+2 cx x-x^2],2 a-Sqrt[a^2-cx^2+2 cx > x-x^2]},{cy,-Sqrt[a^2-cx^2+2 cx x-x^2]+y,Sqrt[a^2-cx^2+2 cx > x-x^2]+y}},{{x,a,2 a},{cx,-a+x,2 a},{y,2 a-Sqrt[a^2-cx^2+2 cx x-x^2],2 > a},{cy,-Sqrt[a^2-cx^2+2 cx x-x^2]+y,2 a}}}; > > I want to integrate over each of these regions using an integrand of 1. I > want my output to be as follows: > > {Integrate[1,{x,0,a},{cx,0,a+x},{y,0,Sqrt[a^2-cx^2+2 cx > x-x^2]},{cy,0,Sqrt[a^2-cx^2+2 cx > x-x^2]+y}],Integrate[1,{x,0,a},{cx,0,a+x},{y,Sqrt[a^2-cx^2+2 cx x-x^2],2 > a-Sqrt[a^2-cx^2+2 cx x-x^2]},{cy,-Sqrt[a^2-cx^2+2 cx > x-x^2]+y,Sqrt[a^2-cx^2+2 cx x-x^2]+y}],Integrate[1,{x,0,a},{cx,0,a+x},{y,2 > a-Sqrt[a^2-cx^2+2 cx x-x^2],2 a},{cy,-Sqrt[a^2-cx^2+2 cx x-x^2]+y,2 > a}],Integrate[1,{x,a,2 a},{cx,-a+x,2 a},{y,0,Sqrt[a^2-cx^2+2 cx > x-x^2]},{cy,0,Sqrt[a^2-cx^2+2 cx x-x^2]+y}],Integrate[1,{x,a,2 a},{cx,-a+x,2 > a},{y,Sqrt[a^2-cx^2+2 cx x-x^2],2 a-Sqrt[a^2-cx^2+2 cx > x-x^2]},{cy,-Sqrt[a^2-cx^2+2 cx x-x^2]+y,Sqrt[a^2-cx^2+2 cx > x-x^2]+y}],Integrate[1,{x,a,2 a},{cx,-a+x,2 a},{y,2 a-Sqrt[a^2-cx^2+2 cx > x-x^2],2 a},{cy,-Sqrt[a^2-cx^2+2 cx x-x^2]+y,2 a}]} > > How can I do that without having to set up each of the integrals manually? > I am looking for some way to do something like: > > Integrate @@ regions > > or > > Integrate @@@ regions > > But I can't figure out how to incorporate the 1 as the integrand when I try > to set this up automatically. > > There must be a way? > > Thanks, > > John > >