[Help-smalltalk] [bug] FloatQ pi is not the extended precision nearest pi

[Nicolas Cellier]

Issue status update for 
http://smalltalk.gnu.org/node/312
Post a follow up: 
http://smalltalk.gnu.org/project/comments/add/312

Project:      GNU Smalltalk
Version:      <none>
Component:    Base classes
Category:     bug reports
Priority:     normal
Assigned to:  Unassigned
Reported by:  nice
Updated by:   nice
Status:       active

I get a surprising result:

> FloatD pi sin abs < FloatQ pi sin abs.
true

Let pi be an exact representation.
I expect (pi - FloatD pi) abs > (pi - FloatQ pi) abs
And thus same relation-ship between sin...

I suspect FloatQ pi is not the nearest to pi:
> (FloatQ class>>#pi) methodSourceString
'pi [
      "Returns the value of pi. Hope is that it is precise enough"

      
      ^3.1415926535897930885169542232694q
  ]'

In contrast, the first decimals I compute are:
3.1415926535897932384626433832795028841971693993751058209749445923078164062862
3.1415926535897930885169542232694q
3.141592653589793d
3.1415928e

And this one is consistent with what I compute:
> -1.0q arcCos
3.1415926535897932385

So I presume this is worth a bug report