** Using WeBWorK **

First, thanks again for all your help! I'm learning so much (although I'm daunted by how much I still don't understand).

So, I've now got the original problem to work as intended, by moving the Context("Vector"); call to after the lines changing <> to ().

But I haven't yet succeeded in doing it the "right" way, using parserCustomization.pl.

I didn't want to mess around in the templates directory in the Webwork course that we're all sharing, so I did it in the course that's set up for me to use next fall, on a local server.

The version info at the bottom of each page for that Webwork course is

WeBWorK © 1996-2015 | theme: math4 | ww_version: 2.10 | pg_version: 2.10

if that matters.

Anyway, I made a file called parserCustomization.pl and I put it in the templates directory. The text of that file was as follows:

################################################################################
# WeBWorK Online Homework Delivery System
# Copyright � 2000-2007 The WeBWorK Project, http://openwebwork.sf.net/
# $CVSHeader$
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of either: (a) the GNU General Public License as published by the
# Free Software Foundation; either version 2, or (at your option) any later
# version, or (b) the "Artistic License" which comes with this package.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See either the GNU General Public License or the
# Artistic License for more details.
################################################################################

=head1 NAME

parserCustomization.pl - Placeholder for site/course-local customization file.

=head1 DESCRIPTION

# From https://raw.githubusercontent.com/openwebwork/pg/master/macros/parserCustomization.pl

# Copy this file to your course templates directory and put any
# customization for the Parser that you want for your course
# here. For example, you can make vectors display using
# ijk notation (and force students to use it for entering
# vectors) by using:

# $context{Vector} = Parser::Context->getCopy("Vector");
# $context{Vector}->flags->set(ijk=>1);
# $context{Vector}->parens->remove('<');

# To allow vectors to be entered with parens (and displayed with
# parens) rather than angle-brakets, use

$context{Vector} = Parser::Context->getCopy("Vector");
$context{Vector}->{cmpDefaults}{Vector} = {promotePoints => 1};
$context{Vector}->lists->set(Vector=>{open=>'(', close=>')'});

# (This actually just turns points into vectors in the answer checker
# for vectors, and displays vectors using parens rather than angle
# brackets. The student is really still entering what MathObjects
# thinks is a point, but since points get promoted automatically, that
# should work. But if a problem checks if a student's value is actually
# a Vector, that will not be true.)

=cut

sub _parserCustomization_init {}

1;

(I used the text from
https://raw.githubusercontent.com/openwebwork/pg/master/macros/parserCustomization.pl
and commented out the bits I thought I didn't need.)

Then I put the following problem in a subdirectory of templates:

DOCUMENT();

loadMacros("PGstandard.pl",
"MathObjects.pl",
"PGML.pl");

Context("Vector");

$v1 = Vector(random(-10,10,1),random(-10,10,1),random(-10,10,1));
$v2 = Vector(random(-10,10,1),random(-10,10,1),random(-10,10,1));

TEXT(beginproblem());
BEGIN_PGML
[$v1] + [$v2] = [________]*{$v1+$v2}
END_PGML

ENDDOCUMENT();

It worked without errors, but the vectors were in angle brackets instead of parentheses.

I also tried adding parserCustomization.pl to the loadMacros bit:

loadMacros("PGstandard.pl",
"MathObjects.pl",
"PGML.pl",
"parserCustomization.pl");

but it didn't make a difference; the vectors were still rendering with angle brackets.

Any idea what I'm doing wrong?