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4. Developing Your Own Pages

Once  you  have  installed  and  configured  a  webMathematica  server  so  that  the  examples  run  correctly  and  have

studied the basics of writing material for webMathematica, as described 

previously

, you are ready to start develop 

ing your own material.

One  way  to  start  is  to  make  your  own  area  in  the  webMathematica  web  application.  You  could  make  a  directory

here  (for  example  NewScripts)  and  copy  one  of  the  samples  (for  example  Plot.jsp)  from  the  Examples

directory.  You  could then  access this  script  with the  URL http://localhost:8080/webMathematica/ 

NewScripts/Plot.jsp.

This  might  be  a  good  time  to  revisit  the  webMathematica  index  page  found  at  http://localhost:8080/web 

Mathematica/index.html,  which  provides  a  number  of  links  that  demonstrate  features  of  webMathematica.  When

you actually want to write your own material  you may look at the 

Tips and Tricks

 described in this chapter. The

chapter continues to describe other page development utilities that are part of webMathematica.

4.1 Tips and Tricks

This section provides a summary of a few issues that will help you to get started writing your own pages. These are

all described in more detail in later sections of the User Guide, but are collected together here in a brief description.

Getting a good grasp of these points will help you to make progress in developing your site.

4.1.1 Variables

There are two types of variable that are important to understand when you are getting started with webMathematica:

input variables and page variables.

Input variables  come with the HTTP request, for example from an input field in an HTML form. You can identify

input  variables  in  Mathematica  code  because  they  are  labelled  with  a   $$   prefix.  In  the  example  below  the  set 

ting variable may be set by an input field. In Mathematica code it is called $$setting.

If[ MSPValueQ[ $$setting], 

....

]

You  should  be  aware  that  input  variables  are  a  potential  security  risk  to  your  server  and  should  always  use  the

special functions, MSPBlock and MSPToExpression, for converting  into Mathematica input. In particular, you

should never use ToExpression on an input variable. An example of using MSPBlock is shown below.

 .