Re: [ferret_users] z range (z=zz:zzz) doesn't limit the plotting within the range

["Ansley C. Manke" <ansley.b.manke@xxxxxxxx>]

Hi Ryo,

The VECTOR/Y= /Z=  qualifiers are used to choose the subset of the data that will be sent to the plotting command. With this dataset, the coordinate value of the grid box that contains z=900 is 915.4, so the subset of data that you've requested includes data at z=289, 320, ..., 915.4. 

yes? list/y=30S/z=300:900 mv

             VARIABLE : V1[X=113:113.9@DIN,L=14:33@AVE]/100/FAC
             FILENAME : mv-mw.nc
             SUBSET   : 10 points (DEPTH (m))
             LATITUDE : 30.1S
 289    / 25:  2.683
 320.8  / 26:  2.858
 359.7  / 27:  2.911
 406.7  / 28:  2.764
 463.1  / 29:  2.361
 529.7  / 30:  1.757
 607.5  / 31:  1.020
 697.3  / 32:  0.335
 799.7  / 33: -0.243
 915.4  / 34: -0.538

The qualifiers /VLIMITS or /HLIMITS can be used to set the plot axis ranges differently than the data subset given by the context that's in effect, but then the PPL WINDOW setting determines whether the data may be drawn outside that box.  You're right that the PPL WINDOW off is allowing vector arrows outside of the plot box to be plotted.

-Ansley

On 3/5/2018 11:47 PM, Ryo Furue wrote:

Dear Ferret users,

I'm puzzled why

     vector/z=300:900/ . . . v, w

plots vectors below 900 m.  PPL WINDOW,OFF seems to be causing it, but I thought the z range is sufficient to prevent it.  (If the z range is ignored, vectors should be plotted all the way down to the bottom, which is at 6000 m.)

A sample script, the data file, and a sample plot are attached.  (It's actually an extension of the same script I showed a few days ago.)

Regards,

Ryo

! =============

set mode grat:dash

set data mv-mw.nc

let fac = 1e3 ! velocity-length scale

define symbol y1_ 30S

define symbol y2_ 28S

let z2_ = 900

!-------

!go init-print

let samp_vec_in_ = 0.45

let samp_vec_ = fac/200

vector/aspect/hlimits=($y1_):($y2_)/vlimits=0:`z2_`:50/color=red\

/y=($y1_):($y2_)/z=0:100/set mv,mw

  ppl WINDOW,OFF

  ppl vecset,`samp_vec_in_`,`samp_vec_`

ppl vector,2,3

vector/aspect/nolabel/color=blue\

/y=($y1_):($y2_)/z=94:300/OVER/set mv,mw

  ppl vecset,`samp_vec_in_`,`samp_vec_`

ppl vector/ov,2,1

vector/aspect/nolabel/color=red\

/y=($y1_):($y2_)/z=300:`z2_`/OVER/set mv,mw

  ppl vecset,`samp_vec_in_`,`samp_vec_`

ppl vector/ov,2,1

!go finish-print try-vector-overlay 3 false