Re: $Assumptions

*To*: mathgroup at smc.vnet.net*Subject*: [mg92629] Re: $Assumptions*From*: Albert Retey <awnl at gmx-topmail.de>*Date*: Thu, 9 Oct 2008 06:34:03 -0400 (EDT)*References*: <gci2ia$ta$1@smc.vnet.net>

Hi, > I seem to be unable to change some default options globally. > > At the top of my notebook I have > > $Assumptions = {MaxRecursion -> 30, AccuracyGoal -> 10}; If you want to change default options, use SetOptions. Changing $Assumptions will not have any effect on NIntegrate, except that you might introduce unintended side effects. This should do what you want: SetOptions[NIntegrate,MaxRecursion -> 30, AccuracyGoal -> 10] you can even check that this has been succesful by evaluating: Options[NIntegrate] > Then we I evaluate NIntegrate[Exp[-x^2], {x, 20., 40.}] > I get 4.78196*10^-176 > > But if I evaluate NIntegrate[Exp[-x^2], {x, 20., 40.}, MaxRecursion -> 30, > AccuracyGoal -> 10] > I get quite a different value, 1.36703*10^-177 > > I had the same problem trying to change the options for fonts in plots, > and then I had to add the options I wanted > in every plot, I mean evaluation something like $TextStyle ={whatever} > before doing the plots did not work. Same story here: You need to change the Options of Plot: SetOptions[Plot, BaseStyle -> {FontSize -> 20}] >From the documentation: "As of Version 6.0, $TextStyle has been superseded by BaseStyle and other options." There have been complaints about the documentation, but still I think it is a good idea to first look there if something doesn't work as expected... hth, albert