
NCL Graphics: Wind Barbs
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Wind barbs are a vector style, so the normal vector resources
work to control the look and feel of wind barbs.

vcGlyphStyle = "WindBarb" turns on wind barbs.
In this example, vcMinDistanceF is used to control the density of the wind barbs. The default density blacks out the entire plot. The length of the barbs is controlled by vcRefMagnitudeF and vcRefLengthF

vcMonoWindBarbColor will color the wind barbs by the scalar field rather than plot them on top of the scalar field.
gsn_csm_vector_scalar_map is the plot interface that draws either vector quantities on a scalar field, or colors those quantities by the scalar field.

vcRefAnnoOn turns off the reference wind barb since by nature it is not needed.
vcWindBarbTickLengthF controls the length of the wind barb ticks. Default is 0.3.
vcWindBarbTickSpacingF controls the distance between the wind barb ticks. Default is 0.125.
Because this is a non-global plot, we must set gsnAddCyclic to False
mpDataBaseVersion allows the user to select the coastline data base. See the coastline example page for more details.

Note that any plot object can be overlaid on a logLin plot to make the Y-axis linear or logarithmic. (You would not want to do this when working with certain plot types, a map plot for instance.)

In example 4, gsn_csm_vector_scalar was used to draw a wind profile plot. One reason not to use gsn_csm_vector_scalar is if your data at each timestep has values at different levels. This can be the case with wind profiler data. In this example profiler data is read in from three ascii files and plotted on a blank plot created by gsn_csm_xy. Each wind barb is drawn separately by using wmbarb and colored according to its wind speed. Finally, a labelbar is drawn by calling gsn_labelbar_ndc.
