NAME: CDAWEB_VELOVECT PURPOSE: To plot a velocity field (uses normalized coords) on a map CALLING SEQUENCE: cdaweb_velovect,u,v,x,y INPUTS: u = x component of the 2D field. v = y component of the 2D field. The vector at point [i,j] has a magnitude of: (U[i,j]^2 + V[i,j]^2)^0.5 and a direction of: ATAN2(V[i,j],U[i,j]). x = abcissae values, latitudes y = ordinate values, longitudes KEYWORD PARAMETERS: latpass = Initial latitude of each particular pass lonpass = Initial longitude of each particular pass missing = Missing data value. (fillval) length = Length factor. The default of 1.0 makes the longest (U,V) vector the length of a cell. error = 0=ok, -1=error occurred color = The color index used for the plot. Note: All other keywords are passed directly to the PLOT procedure and may be used to set option such as TITLE, POSITION, NOERASE, etc. OUTPUTS: None. AUTHOR: Rita Johnson 12/2004. Based on velovect.pro MODIFICATION HISTORY: