On Wed, 11 Apr 2007, Tom Lane wrote:
Kris Jurka <[EMAIL PROTECTED]> writes:
Why doesn't setseed complain when given a seed value outside of its
expected range?
Why should it complain? The use of the value is totally unspecified
anyway.
Because the user is likely using it incorrectly. I'm not sure what you
mean by totally unspecified. The documentation[1] states:
set seed for subsequent random() calls (value between 0 and 1.0)
When a user calls setseed(5), setseed(500), or setseed(-500) they get the
same seed value each time which is surely not what they intended. At
minimum I think it should raise a warning.
Also I think that documentation should be corrected to indicate that
vaules -1 to 1 are the correct seed value range or it should it should map
0->1 to the entire seed space, not just half of it as is currently done.
The decision of which change to make is unclear because it's a change to
either the call signature or to the generated values for a given user
supplied seed.
Kris Jurka
[1]
http://www.postgresql.org/docs/8.2/static/functions-math.html#FUNCTIONS-MATH-FUNC-TABLE
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