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hcrisp
11-12-2009, 02:17 PM
Ok, I am getting a wierd behavior from SIMPLESTAT. Why does it give an alert for a double vector when it doesn't for the same values as float?



x = RANDOMU(s, 196)
xd = DOUBLE(x)
res = SIMPLESTAT(x)
res = SIMPLESTAT(xd)
; %%%FFTCOMP: Alert: STAT_NORMAL_UNDERFLOW
; The normal distribution is used for large degrees of freedom. However,
; it has produced underflow. Therefore, the probability is set to zero.

donb
11-13-2009, 07:31 AM
Hi hcrisp,

Looking at the documentation for SIMPLESTAT, my first thought was the omission of the /Double keyword is why you see the 'SIMPLESTAT: Alert' message. Underneath the single call to SIMPLESTAT, it branches to call either the float version or the double version of SIMPLESTAT within the integrated CNL libraries; controlled by the /Double keyword.

However, when I added the /Double keyword it didn't make a difference; still saw the Alert. BTW, this is true for PV-WAVE v8.00, which I believe is the version you are running.

When I run PV-WAVE v8.50, v8.51, v9.00 or v9.01, there is no alert.

hcrisp
11-23-2009, 08:23 AM
So which changed, the PV-WAVE routine or the CNL? Do you still get the same numerical results?

Just to wrap up, I dealt with the alert message in 8.00 by setting the !QUIET to 2 before calling SIMPLESTAT.

Cheers.

donb
11-24-2009, 10:28 AM
Hi hcrisp,

The underlying CNL versions has changed; PV-WAVE v8 uses CNL 5, PV-WAVE v8.5 uses CNL 5.5, and PV-WAVE v9.0 uses CNL 6.

The PV-WAVE wrapper (.pro) has not changed in any of the PV-WAVE versions.

I'll get back with another post once I've compared the output of the various versions.

Don B.

donb
11-24-2009, 03:04 PM
Hi hcrisp,

The answer to your second question is yes - you get identical numerical results.

Don B.