owner-csound-outgoing wrote
>From owner-csound-outgoing Tue Aug  5 07:04:20 1997
From: owner-csound-outgoing
Date: Tue, 5 Aug 97 07:04:20 GMT
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To: owner-csound-outgoing
Subject: BOUNCE Csound: Non-member submission from [Eli Brandt ]

>From eli@gs160.sp.cs.cmu.edu Tue Aug  5 08:04:16 1997 remote from 
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Subject: airplane flange
To: Csound mailing list 
Date: Tue, 5 Aug 1997 03:04:43 -0400 (EDT)
From: Eli Brandt 
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This is not strictly on-topic, but I figure somebody here has likely
looked at this problem...

The difference between the direct and ground-bounce paths is:
        sqrt(x^2 + (y+y_ear)^2) - sqrt(x^2 + (y-y_ear)^2)
but this is numerically unstable.  Squaring and juggling and squaring
and juggling resulted in a marker-fume headache and yet another unstable
form.  Has anybody got a stable way to calculate or approximate this?
(Approximate for x comparable to y, that is -- the extremes are easy
enough.)

thanks,
-- 
     Eli Brandt  |  eli+@cs.cmu.edu  |  http://www.cs.cmu.edu/~eli/


-- 
James Andrews, maths CDO, ext.3977