Re: Direction Fields
- To: mathgroup at smc.vnet.net
- Subject: [mg2088] Re: Direction Fields
- From: kluge at seuss.cc.utexas.edu ()
- Date: Fri, 29 Sep 1995 01:13:49 -0400
- Organization: Computation Center, University of Texas
nprive at mbhs.edu (Nikki Prive ) asks:
in an attempt to create direction fields ... My textbook says
I must first type ">>Graphics`PlotField`
Your problem here is in part do to an incorrect Mathematica syntax.
The syntax to read in this package is "<<Graphics`PlotField`", with
<<, not >>. This produces the error message:
Syntax::sntxf:
">>Graphics`PlotField" cannot be followed by "`".
However, this still leaves your first problem. The first error message
is the result of reading in the package (so I think you had the right
syntax that time), which defines the function PlotVectorField. Somehow
this function has already been defined to Mathematica. Try to reload the
Graphics`PlotField` package, with the correct syntax, as the FIRST thing
you do when you start Mathematica. If the
Warning: Symbol PlotVectorField appears in multiple contexts
persists, then it is likely that you are preloading the PlotField
package, i.e. it is loaded automatically for you when Mathematica
starts. If this is the case then you can use PlotField without
having to load any packages.
Hope this helps,
A. Kluge
The University of Texas at Austin