Draws a contour plot from longitude/latitude data stored in a 2D array.
A two-dimensional array containing the longitude/latitude values that make up the contour surface.x
(optional) A vector specifying the longitude coordinates for the contour surface. y
(optional) A vector specifying the latitude coordinates for the contour surface.
When this keyword is set, MAP_CONTOUR first projects the grid of z values, grids the resulting projected points to a regular grid and performs the contouring in cartesian (data coordinate) space. This keyword allows you to get labeled contours and contours that can encircle a pole in a polar map. (Default: off) File_Path
(string) The file pathname for a temporary file used by MAP_CONTOUR. This keyword is optional. See the Discussion section for more information.Filled
If present and nonzero, fills the contours.Iter, Nghbr
These keywords are used in conjunction with the Cartesian keyword and control parameters to the FAST_GRID3 function, which is used to perform gridding of the z grid data after applying the map projection. See the FAST_GRID3 documentation for a description of these parameters.
Pattern
A rectangular array of pixels giving the fill pattern.
| C_Annotation | C_Thick | NLevels | |
| C_Colors | Font | Path_Filename | |
| C_Charsize | Follow | Pattern | |
| C_Labels | Levels | Spline | |
| C_Linestyle | Max_Values |
Each element of x specifies the longitude coordinate for a column of z. For example,
X(0) specifies the longitude coordinate for Z(0, *).Each element of y specifies the latitude coordinate for a row of z.
In addition to line plot overlays, the Filled and Pattern keywords allow contours to be filled.
new_array = REPLICATE(MIN(array1), m+2, n+2) ;Create a background array that is two elements larger than ;the original array, array1 new_array(1, 1) = array1 ;Insert original data into the new array.
TIP: You cannot use the Filled keyword to fill contours when the projection is set to 99 (Satellite View); however, it is possible to place filled contours on a satellite projection. To do this, create a 2D image using CONTOUR and CONTOURFILL, or by using the CONTOUR2 procedure with the Fill keyword, and then use the Image keyword with the MAP procedure to wrap the image on the globe.
wvctmp.dat and placed in your current directory. You can override this filename and path using the File_Path keyword with MAP_CONTOUR. This allows you to specify a string containing the path to a temporary file. This file is deleted when MAP_CONTOUR is finished plotting.
data = HANNING(20,20)
MAP, Projection = 4, range = [-150, 30, 30, 70] MAP_CONTOUR, data, NLevels=10
