At 09:37 AM 31 10 00 -0500, you wrote:
>Does anyone view DUMMY values in a significantly different manner than I
>have outlined above?
Joseph,
I agree with you completely. Dummy values are treated as rDummy (-1e32) in comparison
operations. This is documented somewhere, but it's still dumb.
Here's another one that REALLY bugs me. If you run a math expression on several
existing channels, either interactively or by using the Math gx. The sample rate of
the output channel is determined by the displayed fid level. For example if a create a
new channel Test, and run Math.gx with the expression Test=xf+2, if xf is sampled at 1
x/sec I would expect Test to be the same. It will, however, be sampled at whatever the
displayed fid is at the time. If I have mag displayed which is 10 x/sec, and that is
my master sample, then Test will be at 10x. If xf is my master sample then the output
will be 1x. The math gx is somehow using the database display to determine fiducial
rate.
There's another twist to this as well. If Test already exists and is at 10x, but my
displayed fid increment is at 1x and I again run Test=xf+2, the fid increment remains
0.1. There is a certain logic to that, I guess, but if it happens the other way, Test
exists at 1x and you run test=mag, then test comes out at 10x, regardless of the
displayed fid level.
The end result of all that is when you work with a given database for long enough, all
of your channels end up resampled at the highest sample rate. Well, that's what
happens here anyway.
The moral of this story, when working with differing sample rates never reuse channels
for temporary output, as they preserve the highest sample rate, and always confirm
that the sample rate of your output channel matches the inputs. Oasis loves to bloat
up those databases.
cheers
Marc Pelletier
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