Re: [ferret_users] restrict polymark to transect

[Ryo Furue <furue@xxxxxxxxxx>]

Hi Marco,

>> I regularly plot transects of model output with observations plotted
>> on top of these as dots.  So the last command is
>>
>>   go polymark polygon/over Latitude, Depth, myvar circle 1.0
>>
>> for a transect that is monotonic in latitude.
[. . .]
> Paulo and Ryo suggested that I could define a mask for this.  I am
> trying to extend this to an arbitrary number of stations with
> coordinates (TransLon, TransLat).  The coordinates of my data are
> (Longitude, Latitude).  Of the latter I have many more points, so the
> two datasets do not share a common shape, so Ryo's method will not work
> in my case.

In that case, I suppose you can use the coordinates of your data to
define your mask:

   let masked_var = if x[g=var] lt somelon then var

The special variable "x" represents the x coordinates of the variable
associated with it ("[g=var]").

Ryo