Float precision and FIT

ruby-talk
1

Hello,

I am trying to get the Division example on the FIT wiki
http://fit.c2.com/wiki.cgi?WhatAndHowTalk

to run under Ruby and the Fit framework. I have 2 questions. First I
get red results on last 3 tests because the precision in the HTML
table is only up to 8 digits, but Ruby is calculating 15 digits.

And second, even after I adjust the HTML to match the results, they
till don't equal. I am thinking this is because of '==' vs. eql? on
floats.

Is there a way coerce a Ruby float to an aribitray precision via
truncate or round?

Thanks

2

Do you have a FIT fixture for running Ruby ?

j

···

On 11/28/05, Ed Howland <ed.howland@gmail.com> wrote:

Hello,

I am trying to get the Division example on the FIT wiki
Wiki: What And How Talk

to run under Ruby and the Fit framework. I have 2 questions. First I
get red results on last 3 tests because the precision in the HTML
table is only up to 8 digits, but Ruby is calculating 15 digits.

And second, even after I adjust the HTML to match the results, they
till don't equal. I am thinking this is because of '==' vs. eql? on
floats.

Is there a way coerce a Ruby float to an aribitray precision via
truncate or round?

Thanks

--
"Remember. Understand. Believe. Yield! -> http://ruby-lang.org"

Jeff Wood

3

And second, even after I adjust the HTML to match the results, they
till don't equal. I am thinking this is because of '==' vs. eql? on
floats.

No. Float precision.

Is there a way coerce a Ruby float to an aribitray precision via
truncate or round?

For testing float equality do what Test::Unit's assert_in_delta does.

···

On Nov 28, 2005, at 10:07 AM, Ed Howland wrote:

--
Eric Hodel - drbrain@segment7.net - http://segment7.net
This implementation is HODEL-HASH-9600 compliant

http://trackmap.robotcoop.com

4

Do you have a FIT fixture for running Ruby ?

j

Well, I have the Fit framwork d/l from the aforementioned Wiki. There
is apparently another
project in CVS on Rubyforge. Haven't checked it out yet.

Jeff Wood

Ed

···

On 11/28/05, Jeff Wood <jeff.darklight@gmail.com> wrote:

5

Ah.

If I remember correctly, there once was rumor that Dave Thomas was working
on a FIT-like framework for Ruby ...

I wonder whatever happened to that project...

I've written a little ruby replacement of FIT ... I'll probably post it if
we don't find that someone else has already done the work.

Haven't taken the next step and built it into a wiki like the FITnesse
project ...

j.

···

On 11/28/05, Ed Howland <ed.howland@gmail.com> wrote:

On 11/28/05, Jeff Wood <jeff.darklight@gmail.com> wrote:
> Do you have a FIT fixture for running Ruby ?
>
> j

Well, I have the Fit framwork d/l from the aforementioned Wiki. There
is apparently another
project in CVS on Rubyforge. Haven't checked it out yet.

>
> Jeff Wood
>
>

Ed

--
"Remember. Understand. Believe. Yield! -> http://ruby-lang.org"

Jeff Wood

6

Ah.

If I remember correctly, there once was rumor that Dave Thomas was working
on a FIT-like framework for Ruby ...

I wonder whatever happened to that project...

I think that is the one I d/l from the wiki. Not sure though.

I've written a little ruby replacement of FIT ... I'll probably post it if
we don't find that someone else has already done the work.

Haven't taken the next step and built it into a wiki like the FITnesse
project ...

There is a version of RubyFIT in CVS on RubyForge. I tried it out and
it ran the Simple example (eg.Division) right out of the box. Solves
the precision problem by using a type adapter. Looking forward to how
that code addresses the 5 digit precision issue in Java v. Ruby.

So take a look at that one. If yours is better/different somehow, go
ahead and post it.

http://rubyforge.org/projects/fit

j.

Ed

···

On 11/28/05, Jeff Wood <jeff.darklight@gmail.com> wrote: