GIS Vector Plots

Selected from the PLOT button on the table display window.



 

Select properties for the vector overlay:

  • Polar coordinates, or x and y compenents.  The appropriate option depends on the data set.
  • Thin: if there are a lot of points close together, you can plot only every nth record to make the map clearer.  If this value is too large, you may not see enough vectors to understand the patterns.  Larger values will also be faster to plot.
  • Fields to use for  direction and magnitude, or u and v components.  The direction is assumed to be the direction in which the vector points.
  • Line width and color.  Color only applies if you select "Specified" for the color display.
  • Line multiple.  This will be multiplied by the value in the magnitude field of the data base, and give the length in pixels of the line.
  • Color by max speed: set this value, and the rainbow color range will go from 0 to this value.
  • Arrowhead on the vector. or not.
  • Reverse arrows: for the direction of the vector for the arrowhead.  This is appropriate for winds, which are by convention given as the direction from which the wind blows.
  • Autospace: insures the min spacing in pixels separates adjacent vectors.  This should only be used for data sets on a regular grid.

 

Color options --select how vectors are colored.
 

Pick months: (only available for data sets with month field when you want to see the annual cycle)

Bottom panel controls:

 

Vector overlay of surface wind vectors in the vicinity of Hawaii from historic ship logs from 1750 to 1850.

 

 


Last revision 1/7/2017