Re: Convolution Integral

*To*: mathgroup at smc.vnet.net*Subject*: [mg72735] Re: Convolution Integral*From*: "dimitris" <dimmechan at yahoo.com>*Date*: Wed, 17 Jan 2007 06:28:39 -0500 (EST)*References*: <eoht0r$pti$1@smc.vnet.net>

Hello. Here is one place to look. http://mathworld.wolfram.com/Convolution.html Cheers, Dimitris Mr Ajit Sen wrote: > Dear Mathgroup, > > Could anyone please help me with the following? > > I'd like to find the convolution of 2 arbitrary > functions, f(t) and g(t) in the Laplace transform > sense,i.e., > > convolve[f[t],g[t]]=Integrate[f[u]*g[t-u],{u,0,t}] > > Thus, I'd like convolve[Sin[t],Exp[-t]] to return > > (Exp[-t]-Cos[t]+Sin[t])/2 . > > My several attempts with function definitions such as > > convolve[f_,g_]:=Integrate[f[u]*g[t-u],{u,0,t}] > > > convolve[f[t_],g[t_]]:=Integrate[f[u]*g[t-u],{u,0,t}] > > convolve[f_,g_][t_]:=Integrate[f[u]*g[t-u],{u,0,t}] > > all failed (because of the dummy u ? ) > > Thanks in advance. > Sen. > > > > > > > ___________________________________________________________ > Yahoo! Messenger - NEW crystal clear PC to PC calling worldwide with voicemail http://uk.messenger.yahoo.com