Re: How to avoid repeated recalculation of the same function
- To: mathgroup at smc.vnet.net
- Subject: [mg132677] Re: How to avoid repeated recalculation of the same function
- From: Murray Eisenberg <murray at math.umass.edu>
- Date: Sat, 3 May 2014 03:41:15 -0400 (EDT)
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Did you try using Set ( = ) instead of SetDelayed ( := ) when defining f? That is, try: f[x_] = expression On May 2, 2014, at 2:18 AM, pgeipi10 at gmail.com wrote: > Hi, > > I'm doing a calculaton that's purly symbolic (no graphing, numerical integration, etc.). > > Suppose I have a function f[x_]:=... that's very complex to build. In fact, f[x] ends up being a manageable expression (about 30 characters) but it takes Mathematica about 30 min to build that expression. > > Another function g[] uses the function f[x] and references it many times. I've discovered that g[] actually builds f[x] every time it's referenced which takes 30 minutes each time. Theoretically, Mathematica could build it once and then use the resulting expression every time it's referenced. > > So how do I accomplish that? That is, how do I make it build f[x] once and then use the resulting expression when it's needed? > > Thanks, > > > Pavel > Murray Eisenberg murray at math.umass.edu Mathematics & Statistics Dept. Lederle Graduate Research Tower phone 240 246-7240 (H) University of Massachusetts 710 North Pleasant Street Amherst, MA 01003-9305
- References:
- How to avoid repeated recalculation of the same function
- From: pgeipi10@gmail.com
- How to avoid repeated recalculation of the same function