[ncl-talk] Fwd: Random file into polar coordinates

[Mary Haley]

Please see our r, theta plotting examples page at:

http://www.ncl.ucar.edu/Applications/radar.shtml

To be honest, NCL is not tailored for r, theta data, but it *is* possible
to plot it. You have to do some of the work to convert to the coordinate
system you want.

--Mary


On Tue, Nov 7, 2017 at 7:42 PM, Keren Rosado <keren.rosadova at gmail.com>
wrote:

>
>
> Sent from my iPhone
>
> Begin forwarded message:
>
> *From:* Keren Rosado <keren.rosadova at gmail.com>
> *Date:* November 7, 2017 at 4:10:01 PM MST
> *To:* Dennis Shea <shea at ucar.edu>
> *Subject:* *Re: [ncl-talk] Fwd: Random file into polar coordinates*
>
> I have latitude and longitude in cartesian coordinates (example of the
> text file is above). That is the only information I have. I plotted the
> data before using gsn_add_polymarker for the domain I want e.g. 15N 20N
> and 54W-58W. The center of this domain is 16.8N and 56W. What the polymaker
> function did was if I had an observation at 16N and 53W a black dot was
> drawn. What I need now is transform that 16N-53W (black dot)
> into cylindrical coordinates using as center 16.8N and 56W.
>
> On Tue, Nov 7, 2017 at 3:25 PM, Dennis Shea <shea at ucar.edu> wrote:
>
>> Again you need clarify  even more ...Please look at:
>>
>> ---
>>
>>  http://hyperphysics.phy-astr.gsu.edu/hbase/sphc.html
>>
>> Upper left:
>>
>> theta is (90-latitude); co-latitude
>> phi is longitude
>> r is the radius of the earth (assuming a spherical earth)
>>
>> You have all of this information.
>>
>> ===
>> http://keisan.casio.com/exec/system/1359534351
>> ===
>> The radius at any latitude:
>>    http://mathforum.org/library/drmath/view/54158.html
>>
>> r(latitude) = r*cos(latitude)   ; latitude in radians
>>
>>
>>
>>
>> On Tue, Nov 7, 2017 at 1:07 PM, Keren Rosado <keren.rosadova at gmail.com>
>> wrote:
>>
>>> R, theta
>>>
>>> On Tue, Nov 7, 2017 at 12:11 PM, Dennis Shea <shea at ucar.edu> wrote:
>>>
>>>> Please clarify your question:
>>>>
>>>> re: "polar coordinates"
>>>>
>>>> (a)  r,theta ?  https://en.wikipedia.org/wiki/Polar_coordinate_system
>>>> (b)  lat,lon ?
>>>>
>>>> On Tue, Nov 7, 2017 at 11:52 AM, Keren Rosado <keren.rosadova at gmail.com
>>>> > wrote:
>>>>
>>>>>
>>>>> Hello,
>>>>>
>>>>> I have a file with observations for the entire globe for one hour
>>>>> period.
>>>>> Here are few lines from my txt (observations) files. The highlighted
>>>>> values are for lat and lon:
>>>>> 2010/08/28,04:00:00.356732, 11.7047, 133.9177,  4.8,  5
>>>>>
>>>>> 2010/08/28,04:00:00.629722, 36.7353,  52.1856, 26.8,  7
>>>>>
>>>>> 2010/08/28,04:00:00.559602, 36.8155,  52.2482,  3.3,  5
>>>>>
>>>>> 2010/08/28,04:00:00.922721,  4.8667, 105.7474,  8.3,  7
>>>>>
>>>>> 2010/08/28,04:00:00.130999, 22.7165,-105.1758, 24.9,  5
>>>>>
>>>>> 2010/08/28,04:00:00.400279, 11.7329, 133.9220, 16.3,  9
>>>>>
>>>>> 2010/08/28,04:00:01.330873, 21.6459,-105.0242,  7.3,  5
>>>>>
>>>>> 2010/08/28,04:00:01.409443, 28.4564, -90.7360,  9.7,  5
>>>>>
>>>>>
>>>>>
>>>>> I plotted these observations using ncl function gsn_add_polymarker
>>>>> for the domain I am interested in lat and lon.
>>>>>
>>>>>
>>>>> I will like to now how to transform the lat and lon to polar
>>>>> coordinates for the domain I am interested.
>>>>>
>>>>>
>>>>> Does anyone have an idea of how to to this?
>>>>>
>>>>>
>>>>> Thanks!
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> ncl-talk mailing list
>>>>> ncl-talk at ucar.edu
>>>>> List instructions, subscriber options, unsubscribe:
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>>>>>
>>>>>
>>>>
>>>
>>
>
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