[ferret_users] Got Vectors?

[Luke M <coding1227@xxxxxxxxx>]

Hi fellow Ferreters,

I am trying to make a plot using surface currents (water_u & water_v) data (please see below for dataset details), but I'm not exactly sure how to approach this.

Basically, what I'm trying to do is make a simple chart that has a color background that represents the speed of the currents (e.g.: magnitude of water_u & water_v), and on top of that, I want to overlay arrow vectors that only show the direction of the currents where it is going towards (i.e.: all vectors have the same length).

Any guidance with this would be super helpful...

Thanks in advance!
         
yes? set data "http://oos.soest.hawaii.edu/thredds/dodsC/hioos/roms_forec_regridded/hiig/ROMS_Hawaii_Regional_Ocean_Model_Regridded_best.ncd"
yes? show data
     currently SET data sets:
    1> http://oos.soest.hawaii.edu/thredds/dodsC/hioos/roms_forec_regridded/hiig/ROMS_Hawaii_Regional_Ocean_Model_Regridded_best.ncd  (default)
 name     title                             I         J         K         L
 SALINITY salinity                         1:285     1:200     1:33      1:692
 SURF_EL  free-surface                     1:285     1:200     ...       1:692
 WATER_TEMP
          potential temperature            1:285     1:200     1:33      1:692
 WATER_U  u-velocity component             1:285     1:200     1:33      1:692
 WATER_V  v-velocity component             1:285     1:200     1:33      1:692
 TIME_OFFSET
          offset hour from start of run f  ...       ...       ...       1:692
 TIME_RUN run times for coordinate = time  ...       ...       ...       1:692
 
yes? set region/x=159w:154w/y=18n:22n/k=33/t="10-Feb-2013"