Re: Manipulate a complex expression

*To*: mathgroup at smc.vnet.net*Subject*: [mg77875] Re: Manipulate a complex expression*From*: Daniele <d.malleo at gmail.com>*Date*: Tue, 19 Jun 2007 06:29:26 -0400 (EDT)*References*: <f505ip$qug$1@smc.vnet.net><f5328f$2vo$1@smc.vnet.net>

On 17 Jun, 11:26, Januk <ggr... at sarj.ca> wrote: > Hi Daniele, > > On Jun 16, 4:04 am, Daniele <d.mal... at gmail.com> wrote: > <snip>> if I define VolumeFraction (eg. VolumeFraction=0.1) and plot > > Re[MeasuredCMF] vs. f, I have no problem. > > But I am unable to successfully do the following (I get a blank plot) > > > Manipulate[ > > LogLinearPlot[ > > Evaluate[Re[MeasuredCMF]], {f, 1 10^5, 1 10^9}], {{VolumeFraction, > > 0.2}, 0.1, 0.5}] > > <snip> > > You pretty much have it. You just need to force Mathematica to use > the local variable from the Manipulate. One easy way is to use > ReplaceAll to rename VolumeFraction to a temporary variable > (VolumeFraction2): > > Manipulate[ > LogLinearPlot[ > Evaluate[ > Re[MeasuredCMF] /. {VolumeFraction -> VolumeFraction2}], {f, 10^5, > 10^9}], > {{VolumeFraction2, 0.2}, 0.1, 0.5}] > > Good luck! Hello Januk, Thanks for your help. Your suggestion works, but only to a point. For example, in the snippet of code above, if MeauredCMF is a function of VolumeFraction and VolumeFraction itself is a function of a third variable, say Volume, I'm still unable to visualize how Measured CMF changes with Volume, even using ReplaceAll. I'm puzzled because it would seem logical that if a is a function of b and b is a function of c, then a is a function of c. I appreciate your help, Daniele