| Re: Error with MapProjection::Forward [message #86665 is a reply to message #86663] |
Wed, 27 November 2013 05:56   |
atmospheric physics
Messages: 121
Registered: June 2010
|
Senior Member |
|
|
I tried this but still it doesn't work. My corrected code is as below:
; -------------------------------
PRO MELPITZ_GOOGLE_PLOT
CLOSE,/ALL
; DOWNLOAD A MAP
url = "http://maps.googleapis.com/maps/api/staticmap?" + $
"center=51.525517,12.927633&zoom=14&size=600x600" + $
"&maptype=satellite&sensor=true"
netObject = IDLnetURL()
!null = netObject.Get(URL=url, FILENAME="melpitz.png")
netObject = 0
; Load the newly created file
READ_PNG, "melpitz.png", img
; DISPLAY THE MAP IMAGE WITH THE MAP PROJECTION
centerLon = 12.927633D
centerLat = 51.525517D
zoom = 14
Re = 6378137D ; Radius of the Earth
resolution = (2*!DPI*Re)/(256*2D^zoom) ; meters/pixel
PRINT, resolution
; The image is 600 pixel wide by 600 pixel tall
deltax = 600*resolution ; meters
deltay = 600*resolution ; meters
; Convert the map center to spherical Mercator coordinates
; Create a hidden map object to do the conversions.
; Setup map projection, draw a grid
m = MAP('Mercator',/BUFFER, $
SEMIMAJOR_AXIS=6378137D, SEMIMINOR_AXIS=6378137D, $
CENTER_LONGITUDE=centerLon,LIMIT=[51.515D,12.91D,51.540D,12. 95D])
print,m
; Convert from longitude/latitude to meters
uv = m.MapForward(centerLon, centerLat)
; Compute the image bounding box in spherical Mercator coordinates
x0 = uv[0] - deltax/2 ; meters
x1 = uv[0] + deltax/2 ; meters
y0 = uv[1] - deltay/2 ; meters
y1 = uv[1] + deltay/2 ; meters
m.Close
PRINT, [x0, y0, x1, y1]
END
;-----------------------------
I get the same error message ...
% Attempt to call undefined method: 'MAPPROJECTION::MAPFORWARD'.
% Execution halted at: MELPITZ_GOOGLE_PLOT 38
I don't have any clue now!!! Any help to solve this issue will be of great help.
Regards
On Wednesday, November 27, 2013 2:23:47 PM UTC+1, David Fanning wrote:
> Madhavan Bomidi writes:
>
>
>
>> I tried to search in Google for the possible solution to the problem but could not resolve. Am I missing some function files? Please suggest me to resolve this issue and go forward.
>
>
>
> This appears to be a typo. Try this, instead:
>
>
>
> uv = m.mapForward(centerLon, centerLat)
>
>
>
> Cheers,
>
>
>
> David
>
>
>
> --
>
> David Fanning, Ph.D.
>
> Fanning Software Consulting, Inc.
>
> Coyote's Guide to IDL Programming: http://www.idlcoyote.com/
>
> Sepore ma de ni thue. ("Perhaps thou speakest truth.")
|
|
|
|
comp.lang.idl-pvwave archive
Members
Search
Help
Login
Home
