[ncl-talk] hovmoller diagrams for vectors
Adam Phillips
asphilli at ucar.edu
Thu Jul 23 12:28:34 MDT 2015
Hi Qi,
Adding to Dave's email: If you want to reverse your X/Y axes you can set
trYReverse / trXReverse:
www.ncl.ucar.edu/Document/Graphics/Resources/tr.shtml#trXReverse
www.ncl.ucar.edu/Document/Graphics/Resources/tr.shtml#trYReverse
Adam
On Thu, Jul 23, 2015 at 11:58 AM, David Brown <dbrown at ucar.edu> wrote:
> Hi Qi,
> I am guessing you need to set vcMapDirection to False. This needs to be
> set when you plot vectors with axes with coordinates that are not
> geographic.
> -dave
>
>
> On Thu, Jul 23, 2015 at 4:01 AM, LI Qi <liqi123sh at qq.com> wrote:
>
>> Hi Adam,
>>
>> Thank you very much! The example is very helpful! I use the function
>> "overlay" to superimpose vectors over contours.
>>
>> However, the vectors seem different with the one I plot using GrADS (see
>> below), and I don't know why. Could you help me look at my script? One more
>> question is, how to reverse the X-Y coordinates?
>> Attached is the data if it is needed.
>>
>> Much appreciated and best regards,
>> Qi
>>
>> ncl plot:
>>
>> my script:
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/contrib/time_axis_labels.ncl"
>> ;************************************************
>> begin
>> ;************************************************
>> ; variable and file handling
>> ;************************************************
>> in = addfile("erai-qvint-zonmean.nc","r")
>> qu = in->quz(:,:,0)
>> qv = in->qvz(:,:,0)
>> qdiv = in->qflxdiv(:,:,0)
>> time = in->time
>> lat = in->lat
>>
>> ;************************************************
>> ; plotting
>> ;************************************************
>> wks = gsn_open_wks("eps","eri-qhov") ; Opens a eps file
>> ;gsn_define_colormap(wks,"WhiteBlueGreenYellowRed") ;
>> choose colormap
>>
>> res = True
>> res at gsnDraw = False
>> res at gsnFrame = False
>> ;
>> ; Set up some contour resources.
>> ;
>> ; Turn on contour fill, and turn other things off.
>> ;
>> res at cnFillOn = True
>> res at cnLinesOn = False
>> res at cnInfoLabelOn = False
>>
>> ;
>> ; Define contour levels and their colors.
>> ;
>> ;cnres at cnLevelSelectionMode = "ManualLevels"
>> ;cnres at cnMinLevelValF = 980.0
>> ;cnres at cnMaxLevelValF = 1040.0
>> ;cnres at cnLevelSpacingF = 5.0
>> ;cnres at cnFillPalette = "StepSeq25" ; assign color map to
>> contours
>>
>>
>> res at trYReverse = True ; time from top to bottom, small to big
>> ; Set special resources for the time axis
>> resTick = True
>> resTick at ttmFormat = "%d %c" ; form like "1 Jun", %d means day, %c
>> means calendar
>> resTick at ttmAxis = "YL" ; Y axis, Left
>>
>> ; Set resources necessary to customize Y axis labels
>> time_axis_labels( time, res, resTick )
>>
>> vecres = True ; vector only resources
>> vecres at gsnDraw = False
>> vecres at gsnFrame = False
>> vecres at vcRefMagnitudeF = 600000 ; define vector ref mag
>> vecres at vcRefAnnoOrthogonalPosF = -.535 ; move ref vector into plot
>>
>> cnid = gsn_csm_contour(wks,qdiv,res)
>> vcid = gsn_csm_vector(wks,qu,qv,vecres)
>> overlay(cnid,vcid)
>> maximize_output(wks,True)
>> end
>>
>>
>> ------------------ Original ------------------
>> *From: * "Adam Phillips";<asphilli at ucar.edu>;
>> *Date: * Tue, Jul 21, 2015 04:02 AM
>> *To: * "LI Qi"<liqi123sh at qq.com>;
>> *Cc: * "ncl-talk"<ncl-talk at ucar.edu>;
>> *Subject: * Re: [ncl-talk] hovmoller diagrams for vectors
>>
>> Hi Qi,
>> I believe you will want to use the gsn_csm_vector_scalar plotting
>> function. For an example showing how this function is used see example #6
>> here:
>> http://www.ncl.ucar.edu/Applications/overlay.shtml#ex6
>> (see the overlay_6_new.ncl script)
>>
>> This example does not show a latitude/time plot but gsn_csm_vector_scalar
>> should still work for your needs.
>>
>> Hope that helps. If not or if you have further questions please respond
>> to ncl-talk.
>> Adam
>>
>>
>> On Sat, Jul 18, 2015 at 7:29 PM, LI Qi <liqi123sh at qq.com> wrote:
>>
>>> Dear NCL community,
>>>
>>> I would like to create latitude vs. time plot for moisture flux in
>>> vectors.
>>> But the function gsn_csm_lat_time seems to be used for scalar fieids.
>>>
>>> The data I have contains (qu,qv) over a limited area.
>>> Below is a figure I plotted using GrADS for reference. How could I plot
>>> it using NCL?
>>>
>>> Any suggestion would be much appreciated!
>>>
>>> Best,
>>> Qi
>>>
>>>
>>> _______________________________________________
>>> ncl-talk mailing list
>>> ncl-talk at ucar.edu
>>> List instructions, subscriber options, unsubscribe:
>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>
>>>
>>
>>
>> --
>> Adam Phillips
>> Associate Scientist, Climate and Global Dynamics Laboratory, NCAR
>> www.cgd.ucar.edu/staff/asphilli/ 303-497-1726
>>
>> <http://www.cgd.ucar.edu/staff/asphilli>
>>
>> _______________________________________________
>> ncl-talk mailing list
>> ncl-talk at ucar.edu
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>
>>
>
--
Adam Phillips
Associate Scientist, Climate and Global Dynamics Laboratory, NCAR
www.cgd.ucar.edu/staff/asphilli/ 303-497-1726
<http://www.cgd.ucar.edu/staff/asphilli>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20150723/94e53cf0/attachment-0001.html
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 664A2A39 at B0B6B648.89BBB055
Type: application/octet-stream
Size: 270167 bytes
Desc: not available
Url : http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20150723/94e53cf0/attachment-0002.obj
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 2E0CC6FE at B0B6B648.89BBB055
Type: application/octet-stream
Size: 109813 bytes
Desc: not available
Url : http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20150723/94e53cf0/attachment-0003.obj
More information about the ncl-talk
mailing list