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Re: Digital Image CN Exercise
From: Wolfgang Hasper
Date: 2010 Apr 8, 21:38 +0200
From: Wolfgang Hasper
Date: 2010 Apr 8, 21:38 +0200
Greg, you wrote:
> You may need to contact Mr. Umland directly to find
> out what temperature and pressure formulae were used
> in his program.
Or either use the "view source code" option of your
browser that allows you to see all the html...
it is well structured and commented.
####################################
// Altitude corrections
function AltCorr()
{
with(Math)
{
var DIP = 0.02933*sqrt(HE);
var H2 = H1-DIP;
var REF = 1/(tan(DegToRad*(H2+7.31/(H2+4.4))));
var REFcorr = REF-0.06*sin(DegToRad*(14.7*REF+13));
REFcorr *= 0.00467*Pressure/(273+AirTemp);
var H3 = DegToRad*(H2-REFcorr);
var PA = asin(sin(HP)*cos(H3));
if (HP>0.01454441) PA +=
0.0033528*HP*(sin(2*LAT)*cos(Zn)*sin(H3)-sin(LAT)*sin(LAT)*cos(H3));
var H4 = H3+PA;
if (HP>0.01454441) SD = asin(0.272493*sin(HP));
if (limo == "UL") SD = -SD;
if (limo == "Cen") SD = 0;
Ho = H4+SD;
}
}
#####################################
Wolfgang
