Adam Berry at Wolfram responded directly to me about this post,
confirming that the answer to question 1 is Yes. Test[] has an option
called EquivalenceFunction that has default value SameQ but can be
modified arbitrarily. It's easy enough to write a custom
EquivalenceFunction to compare numbers to a given precision or
accuracy. Adam gave the example:
Define
MyEquivalenceFunc[actual_,expected_]:= expected - 0.2 < actual <
expected + 0.2
then use
Test[..., EquivalenceFunction->MyEquivalenceFunc]
If you want it to look neater, or if you often have a need for this
sort of fuzzy comparison when writing your own numerical algorithms,
you might find a use for my (trivial, almost one-line) package
ApproximatelyEqual`. I've uploaded it to http://andrew.j.moylan.googlepages.com/mathematica.
Just look at ApproximatelyEqual.nb to see precisely how it defines
approximate equality (it's based on what I gather Mathematica does in
its own algorithms).
Test[] also has a bunch of other options and arguments that you might
want, such as for testing which messages are generated while
evaluating an expression. Evaluate Options[Test] in a test file, or
just browse the simple source code for MUnit` (located in the
Workbench installation folder).
On Aug 21, 7:14 pm, "Andrew Moylan" <andrew.j.moy...@gmail.com> wrote:
> I want to set up unit tests for a numerical algorithm. I'd like to test the
> timing of the algorithm (and consider 1.00 seconds and 1.02 seconds as the
> same, etc) and the numerical result (and consider 5.6000000000 and
> 5.6000000002 to be the same result, etc).
> 1. Is the testing system in Wolfram Workbench adequate for this purpose? Can
> it do the kind of "fuzzy" comparisons I sometimes require? I can't find much
> documentation on this testing system beyond the screencast athttp://www.wolfram.com/products/workbench/workflow/WorkbenchTesterDem...
> and the small amount of written how-to type information in the Workbench
> help. Can someone point me to more documentation?
> 2. Is there an existing add-on package that is good for this purpose?
> 3. What does Wolfram use internally for unit testing of Mathematica code?
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