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Revision as of 14:43, 20 July 2012 by Dpvc (talk | contribs) (Update some formatting, and link to PGML sample)
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On-line labs for rendering of PG code. These two labs allow you to experiment with PG syntax.

Test your PG code fragments

Click on this link to go to PG calculator:

For example you could enter the code fragment below into the calculator:

   $f = Compute("x^2-3x+5");
   $fp = $f->D; # calculate the derivative
   checkAnswer($fp, "2x-3");      # the first argument is a MathObject, the second the student's answer string
  • On the last line TEXT prints the results of (reading from left to right)
    • Constructing the AnswerEvaluator for the contents of the Formula $fp
    • Evaluating the string "2x-3" using this AnswerEvaluator to produce an AnswerHash
    • Recursively representing the contents of the AnswerHash in a nice table.

checkAnswer() inserts its arguments into a more complicated command. e.g. last line above becomes:


PGML markup lab

  • Experiment with the new PG markup language syntax (PGML) which simplifies the graphical layout of the mathematics question. This is not yet available in the rel-2-4-patches release of WeBWorK but can be used if you update the pg code to HEAD. This is fairly safe since no modifications of configuration files are needed and existing problems are not likely to be affected. (The code base on where many WeBWorK courses are hosted has been updated to HEAD and will run PGML.)

Several dozen questions illustrating the use of PGML:

To use these commands in your own courses you will need a recent version of PG. (You can update by changing to the /opt/pg directory and typing

   cvs update -A   
which will get you the latest version of all of the PG code.  You can move back to the more stable code base by typing
   cvs update -r rel-2-4-patches

Include in your loadMacros() segment. Start the display of your problem text with BEGIN_PGML which expands to


and end with END_PGML. These are used instead of the usual BEGIN_TEXT/END_TEXT construct. You can use both BEGIN_TEXT/END_TEXT and BEGIN_PGML/END_PGML in the same problem, if you wish. See SampleProblem4 for an example (with explanation) that uses PGML.