AnsweredAssumed Answered


Question asked by VRFuser on Jan 24, 1999
send q VRF-Sequencer_Problems vrf

from: Greg Goebel / HP-MXD / 800-452-4844
to:   VRF / Odd T. Pedersen
date: Monday, 25 January 1999 1042 MST


There's a trick with the sequencer.  If you check in the help file under
"Sequencer", it says:


... all tests use an "almost equal" algorithm that checks equality or
inequality to at least six signifcant digits.


The "almost equal" comparison is something of a workaround to the problems
of comparing for equality with real quantities.  I'm not sure myself it's
a good idea, though I couldn't argue it really makes things worse.

It's not in general a good idea to test for equality between real quantities
in *any* programming language (you should use "less than" or "greater than")
and I'm not certain that the "almost equals" just substitutes an artificial
problem for an absolutely unavoidable one.

However, the proper procedure is the same in any case, so it's not like an
issue I feel inclined to belabor the lab team over.  They are good and
competent people and have bigger fish to fry.

[%%] regards -- gvg

> --------------------------------- cut here ----------------------------------
> Date: Mon, 25 Jan 1999 16:01:53 +0100
> From: "Odd T Pedersen" <>
> Subject: vrf: Sequencer problem
> Helo
> I have a problem getting rigth pass or fail information back from the
> sequencer in the attached file.
> Test1 result is out of limit but still the sequencer say pass.
> In test1 the result is 30.000001M and limits are 30.000007M/30.000003M
> and in test2 the result is 30.00001M and limits are 30.00007M/30.00003M
> (This test give the rigth fail/pass inf from sequencer)
> (In my test the result is from a HP5334B  counter)
> I'm using HP Vee 5.0
> What am I doing wrong ??
> Regards
> Odd Pedersen
> Sonec-Kongsberg
    Greg Goebel
    HP MXD Marketing (HP only)