RE: Avoiding Null output marker from a function

*To*: mathgroup at smc.vnet.net*Subject*: [mg92499] RE: Avoiding Null output marker from a function*From*: "E. Martin-Serrano" <eMartinSerrano at telefonica.net>*Date*: Wed, 1 Oct 2008 18:35:47 -0400 (EDT)*References*: <200810011111.HAA11613@smc.vnet.net>

Bill, I think these two similar examples would do. (Maybe Anthony is thinking of other situations, but these seem to pertain to the same inconvenience he is talking about). In[1]:= f[x_] := 20 x^3 + 3 x ^5 In[2]:= Manipulate[{If[g, Plot[f[x], {x, - Pi, Pi}, PlotStyle -> Red]], If[g1, Plot[f'[x], {x, - Pi, Pi}, PlotStyle -> Green]], If[g2, Plot[f''[x], {x, -Pi, Pi}, PlotStyle -> Blue]]}, {g, {True, False}}, {g1, {True, False}}, {g2, {True, False}} ] In[3]:= Manipulate[Show[If[g, Plot[f[x], {x, - Pi, Pi}, PlotStyle -> Red]], If[g1, Plot[f'[x], {x, - Pi, Pi}, PlotStyle -> Green]], If[g2, Plot[f''[x], {x, -Pi, Pi}, PlotStyle -> Blue]]], {g, {True, False}}, {g1, {True, False}}, {g2, {True, False}} ] When the Booleans g, g1 and g2 are unchecked (set to False) the Plot function renders the symbol 'Null'. The convenient output would be void, just to erase the corresponding curve. In the regular situation the symbol =B4'Null' must be dropped "manually" to keep the compound plot clean. $Version = 6.0.1 E. Martin-Serrano ______________________________________________ -----Original Message----- From: Bill Rowe [mailto:readnews at sbcglobal.net] Sent: mi=E9rcoles, 01 de octubre de 2008 12:11 To: mathgroup at smc.vnet.net Subject: [mg92499] Re: Avoiding Null output marker from a function On 9/30/08 at 7:35 AM, Anthony.J.Mannucci at jpl.nasa.gov (amannuc1) wrote: >I am having difficulties that the documentation has not resolved to >date for me. It is this: <problem description snipped> Your problem description failed to include any details of the function creating the problem. Without those details which should include the Mathematica code for the function, it isn't really possible to offer meaningful suggestions as to how to fix the problem.