Re: Pattern matching in functions

*To*: mathgroup at smc.vnet.net*Subject*: [mg54454] Re: [mg54379] Pattern matching in functions*From*: DrBob <drbob at bigfoot.com>*Date*: Sun, 20 Feb 2005 00:11:12 -0500 (EST)*References*: <200502190732.CAA06160@smc.vnet.net>*Reply-to*: drbob at bigfoot.com*Sender*: owner-wri-mathgroup at wolfram.com

Something like this? Cases[l^4*a[b][l] + l*a[c][l], a[x_][y_] -> x, {0, Infinity}] {b,c} or Cases[l^4*a[b][l] + l*a[c][l], a[x_] -> x, {0, Infinity}, Heads -> True] {b, c} or Cases[l^4*a[b][l] + l*a[c][l], a[x_][y_] -> {x, y}, {0, Infinity}] {{b,l},{c,l}} Bobby On Sat, 19 Feb 2005 02:32:49 -0500 (EST), Maximilian Ulbrich <mulbrich at berkeley.edu> wrote: > Hi, > > I would like to find subexpressions using Cases. > In the following case, I expected to find a[b] and a[c] and therefore > get {b,c} as the result. However, I get {l,l}. > What happens and how can I solve this? > > Cases[l^4*a[b][l] + l*a[c][l], x_a[y_] -> y, {0, Infinity}] > > Thanks, > Max > > > > -- DrBob at bigfoot.com www.eclecticdreams.net

**References**:**Pattern matching in functions***From:*Maximilian Ulbrich <mulbrich@berkeley.edu>