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wmlabs

Plots special symbols and icons for daily weather.

Prototype

	procedure wmlabs (
		wks [1] : graphic,  
		x   [*] : float,    
		y   [*] : float,    
		sym [1] : string    
	)

Arguments

wks

An NCL workstation identifier specifying where you want to draw your symbols. The wks identifier is one returned either from calling gsn_open_wks or calling create to create a Workstation object.

x

A one-dimensional array specifying X-coordinate values of points where symbols are to be drawn. If the internal parameter EZF is set to a non-default value (i.e. this function is being used in conjunction with an NCL mapping function), then the X-coordinate values are assumed to be latitudes expressed in degrees. Otherwise the X-coordinates are assumed to be in NCL data units.

y

A one-dimensional array specifying Y-coordinate values of points where symbols are to be drawn. If the internal parameter EZF is set to a non-default value (i.e. this function is being used in conjunction with an NCL mapping function), then the Y-coordinate values are assumed to be longitudes expressed in degrees. Otherwise the X-coordinates are assumed to be in NCL data units.

sym

Specifies what symbol is to be drawn.

Description

The procedure wmlabs uses the WMLABS routine from the Wmap package to plot special symbols and icons for daily weather.

The procedure wmlabs is used to draw special weather map symbols, such as high and low pressure indicators, arrows, dots, weather icons, cloud symbols, lightning bolts, and a sun.

For details on drawing weather symbols, see the section on drawing symbols in the wmap documentation for the lower level utilities.

Certain parameters may be set to control the appearance of the various symbols. The procedure wmsetp is used to set parameter values, and the function wmgetp is used to retrieve parameter values. The parameters applicable to wmlabs are:

EZF - to flag that wmlabs is to be used in conjunction with an NCL mapping function
SHT, HIF, HIB, HIS, HIC - for high symbols
SHT, LOF, LOB, LOS - for low symbols
ARS, AWC, ARD, ASC, AOC, ARL - for arrows
COL, SHT, - for icons
DBC, DTC, DTS - for dots
CC1, CC2, CC3 - for clouds
LC1, LC2, LC3 - for lightning bolts
SC1, SC2, SC3, SC4 - for suns

The procedure wmlabs does not call frame.

See Also

wmbarb, wmbarbmap, wmdrft, wmgetp, wmlabs, wmstnm

Examples

Example 1

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"

;
;  Draw some symbols.
;
begin

;
;  Define a color map and create an X11 workstation.
;
  cmap = (/                      \  
            (/ 1., 1., 1. /),    \  ; color index 0 - white
            (/ 0., 0., 0. /),    \  ; color index 1 - black
            (/ 0., 1., 1. /),    \  ; color index 2 - cyan
            (/ 1., 1., 0. /),    \  ; color index 3 - yellow
            (/ 1., 0., 0. /),    \  ; color index 4 - red
            (/ 1., 0., 1. /),    \  ; color index 5 - magenta
            (/ 0., 0., 1. /),    \  ; color index 6 - blue
            (/ .8, .8, .8 /)     \  ; color index 7 - gray
         /)
  wks = gsn_open_wks("x11","test_wmap")
  gsn_define_colormap(wks,cmap)

;
;  Draw some cloud symbols at random locations.
;
  nums = 200
  wmsetp("cc1",7)     ; Interior of cloud is gray.
  wmsetp("cc2",1)     ; Cloud outline black.
  wmsetp("cc3",6)     ; Cloud shadow blue.
  wmsetp("sht",0.007) ; Set size.

  x = new(nums,float)
  y = new(nums,float)
  s = new(nums,float)
  do i=0,nums-1
    x(i) = rand()/32767.
    y(i) = rand()/32767.
  end do
  wmlabs(wks, x, y, "CLOUD")  ; Draw clouds.

;
;  Draw some suns at random positions and with random sizes.
;
  wmsetp("sc1",3)    ; Yellow for sun center.
  wmsetp("sc2",4)    ; Red for points on sun.
  wmsetp("sc3",1)    ; Black for sun outline.
  wmsetp("sc4",6)    ; Blue for sun shadow.
  do i=0,nums/2
    x(i) = rand()/32767.
    y(i) = rand()/32767.
    size = 0.02*rand()/32767.
    wmsetp("sht",size)              ; Random size.
    wmlabs(wks, x(i), y(i), "SUN")  ; Draw sun.
  end do

  frame(wks)

end