Re: [OpenMap Users] Follow-up to earlier e-mail re: Lat-Lon, azimuth calculations

On Mar 29, 2004, at 10:41 AM, Christopher R. Mamorella wrote:

> Don,
> The GreatCircle class has two methods: sphericalDistance and
> sphericalAzimuth.
> If these 2 functions are applicable to my situation, is it possible to
> convert
> the resulting distance from radians to Nautical Miles?

com.bbn.openmap.proj.Length.NM.fromRadians(val)

>
> SphericalAzimuth returns a value in radians, correct? Thanks.

Yes. The Lenth class also has a DECIMAL_DEGREE static instance for
those conversions.

- Don

>
> -Chris
>
>
>> ===== Original Message From OpenMap Support <openmap@bbn.com> =====
>> Hi Chris,
>>
>> There isn't a class that does these calculations for Rhumb lines. The
>> com.bbn.openmap.proj.GreatCircle class does these calculations for
>> GreatCircle lines.
>>
>> You can probably use the GreatCircle class to do the Rhumb line
>> calculations you want, if you create an OMLine between the two points
>> with LINETYPE_RHUMB, and then inverse project the coordinates back
>> into
>> lat/lon points that describe the rhumb line. Then, you can use the
>> GreatCircle algorithms between the lat/lon points.
>>
>> For determining the azimuth, you would only have to test between two
>> points of the inverse projected set of coordinates, because the
>> azimuth
>> would be constant over all the points.
>>
>> Hope this helps,
>>
>> Don
>>
>> On Mar 26, 2004, at 5:43 PM, Christopher R. Mamorella wrote:
>>
>>> Could you direct me to the openmap class or functions which do the
>>> following:
>>>
>>> Determine the Rhumb-line distance between 2 latitude-longitude
>>> points.
>>> The
>>> distance should be in nautical miles but if a conversion is required
>>> that
>>> would be fine.
>>>
>>> Also, is there a function which determines the azimuth between 2
>>> latitude-longitude points (in Rhumb lines)?
>>>
>>> Thanks,
>>>
>>> Chris
>>>
>
> --
> [To unsubscribe to this list send an email to "majdart@bbn.com"
> with the following text in the BODY of the message "unsubscribe
> openmap-users"]
>
> --
> [To unsubscribe to this list send an email to "majdart@bbn.com"
> with the following text in the BODY of the message "unsubscribe
> openmap-users"]
>

--
[To unsubscribe to this list send an email to "majdart@bbn.com"
with the following text in the BODY of the message "unsubscribe openmap-users"]