Update Value/AnswerChecker diagnostics output.

[somiaj]

Use plots.pl to create the graphs instead of the old graphmacros.

Remove use of tables for formatting. Using bordered divs instead. Only use of a table is for the table of test points, which now uses row headers properly and padding and no longer uses blank cells for spacing. The test point table puts each variable in its own row for multivariable functions.

Here are some test problems, one using an adaptive parameter, and one with multivariables to show each variable test points are put in their own row.

DOCUMENT();
loadMacros('PGstandard.pl', 'PGML.pl');
$ans = Compute('(3 x^4 + 4)/x');
BEGIN_PGML
Enter [``[$ans]``]: [_]{$ans->cmp(diagnostics => 1)}
END_PGML
ENDDOCUMENT();

DOCUMENT();
loadMacros('PGstandard.pl', 'PGML.pl', 'PGcourse.pl');
Context()->variables->are(t => 'Real', C0 => 'Parameter');
$aSoln = Compute('C0 * e^t - 1')->cmp(diagnostics => 1);
BEGIN_PGML
Find one solution to the differential equation.

    [`\frac{dy}{dt} = y + 1`]

[`y =`] [_]{$aSoln}
END_PGML
ENDDOCUMENT();

DOCUMENT();
loadMacros('PGstandard.pl', 'PGML.pl');
Context()->variables->are(x => 'Real', y => 'Real', z => 'Real');
$ans = Compute('(4x - 3y)/z');
BEGIN_PGML
Enter [``[$ans]``]: [_]{$ans->cmp(diagnostics => 1)}
END_PGML
ENDDOCUMENT();

I don't think stating the domain, range, and aspect ratio of the graphs is useful. I left that there, but suggest removing it.

@drgrice1 for some reason the mathjax for the graph labels only renders when clicking on the graph, but not the original graph output. I didn't debug as to why.

[somiaj]

In testing this I ran across a bug where test points were not being graphed correctly when using adaptive parameters, and that was because the adaptive parameters are included in the list of variable names, but don't have test points assigned to them, so the test points being used were either nonexistent or assigned to a different variable depending on the random order of the keys from the variables hash.

So I updated this to remove adaptive parameters from the list of variable names.

I also updated it so that the list of test points only shows the values of variable test points used in either the student or correct answer. This does make the table more useful to me when there are additional variables in the context not used.

[somiaj]

There is another possible issue where alias variables aren't correctly dealt with in determining what the test points are for the graph. I think this is similar to the parameter issue where these variables aren't given test points so the wrong list of test points is chosen to be graphed.

[drgrice1]

@drgrice1 for some reason the mathjax for the graph labels only renders when clicking on the graph, but not the original graph output. I didn't debug as to why.

This is not happening for me. The MathJax renders on initial page load for me.

[somiaj]

@drgrice1 wonder if it is a race condition where mathjax isn't fully loaded by the time the graph loads, I think I've had this happen before.

[somiaj]

Okay, I think I got the variables vs parameters vs aliases figured out. Aliases didn't need to be dealt with as the formula already does the substitution, parameters just need to be filtered otherwise they make the count of which list of test points to use incorrect. @dpvc Care to let me know if I'm missing something, the main bit of code I have is here:

		# Get the test points. This requires first determining what variables are in use and ignore parameters.
		my $points    = [];
		my @params    = $self->{context}->variables->parameters;
		my %pnames    = map { $_ => 1 } @params;
		my @names     = $self->{context}->variables->variables;
		my @variables = grep { !$pnames{$_} } keys %{ $self->{variables} };

		# If a single variable is found, use its test points for the graph.
		# Functions with more than one variable are not graphed so test points are not needed.
		if (scalar(@variables) == 1) {
			my $vi = 0;
			while ($names[$vi] ne $variables[0]) { $vi++ }
			$points = [ map { $_->[$vi] } @{ $self->{test_points} } ];
		}