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Re: Finding distance with longitude and latitude [message #83984 is a reply to message #83983]

Sun, 14 April 2013 18:17

gpeterso
Messages: 22
Registered: February 2013

Junior Member

On Sunday, April 14, 2013 4:49:07 PM UTC-7, wlandsman wrote:
> On Sunday, April 14, 2013 7:45:40 PM UTC-4, wlandsman wrote:
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>> On Sunday, April 14, 2013 7:22:44 PM UTC-4, gpet...@ucsc.edu wrote:
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>>> a=sqrt((cos(lat2)*sin(dlon))^2 + (cos(lat1)*sin(lat2)-sin(lat1)*cos(lat2)*cos(dlon))^2)/(sin( lat1)*sin(lat2)+cos(lat1)*cos(lat2)*cos(dlat))
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>> c= atan(a)
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>> The Wikipedia article you quote says
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>> "When programming a computer, one should use the atan2() function rather than the ordinary arctangent function (atan()), in order to simplify handling of the case where the denominator is zero, and to compute \Delta\widehat{\sigma}\;\! unambiguously in all quadrants"
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> I accidentally hit SEND too soon, but you want to use the two argument form of ATAN, e.g.
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> c = atan( numerator, denominator)
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> --Wayne

When ever i tried to use atan2() it said that the variable was undefined. I dont know why that would happen

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[Message index]

		Re: Finding distance with longitude and latitude By: David Fanning on Tue, 16 April 2013 09:23
		Re: Finding distance with longitude and latitude By: gpeterso on Tue, 16 April 2013 08:46
		Re: Finding distance with longitude and latitude By: seanelvidge on Mon, 15 April 2013 04:13
		Re: Finding distance with longitude and latitude By: wlandsman on Sun, 14 April 2013 19:38
		Re: Finding distance with longitude and latitude By: gpeterso on Sun, 14 April 2013 18:17
		Re: Finding distance with longitude and latitude By: David Fanning on Sun, 14 April 2013 16:57
		Re: Finding distance with longitude and latitude By: wlandsman on Sun, 14 April 2013 16:49
		Re: Finding distance with longitude and latitude By: wlandsman on Sun, 14 April 2013 16:45

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