Defining Functions in a Context

Shows how to add a general function as an input option.

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Complete Code

Download file: DefiningFunctions.pg

POD for Macro Files

PG problem file

Explanation

DOCUMENT();

loadMacros('PGstandard.pl', 'PGML.pl', 'parserFunction.pl', 'PGcourse.pl');

Preamble

Load the parserFunction.pl macro which is used to add a new function to the context.

Context()->variables->are(x => 'Real', y => 'Real');
parserFunction('f(x,y)' => 'sin(x * y) - exp(y)');
$ans = Compute('f(x - 4, 3)');

Setup

Define a function f(x,y). The actual function doesn’t matter but shouldn’t be easily guessed, since a student could enter it and get the answer correct. This is a useful technique for any problem adking is about a generic function rather than a specific one.

BEGIN_PGML
Given a surface defined by [`z = f(x, y)`], what is the equation for the
[`z`]-coordinate of the surface along the line [`y = 3`], shifted four units to
the right?

[`z =`] [_____]{$ans}
END_PGML

Statement

This is the problem statement in PGML. 
BEGIN_PGML_SOLUTION
Solution explanation goes here.
END_PGML_SOLUTION

ENDDOCUMENT();

Solution

A solution should be provided here.