Re: gsnXRefLine

Erika

Have you tried just setting the Fill Color for bars that you don't want to fill to "transparent"?

If that doesn't work then you'll have to adopt the approach I suggested in my original response, which is to plot the histogram for values of xx > 0 and xx < 0 separately using the resources for each that you want, and then overlaying them.

Good luck.

Will

From: Erika Folova <e.folova@gmail.com<mailto:e.folova@gmail.com>>
Date: Sunday, 23 February 2014 9:57 AM
To: Will Hobbs <will.hobbs@utas.edu.au<mailto:will.hobbs@utas.edu.au>>
Cc: NCL-talk <ncl-talk@ucar.edu<mailto:ncl-talk@ucar.edu>>
Subject: Re: gsnXRefLine

Thanks Will,

Actually I want to shade the region where xx <0 with ACTIVE "res@gsnXYBarChartOutlineOnly = True".
so that I'll get the plot as i attached here, but I still do not figure it out in ncl..

On Sun, Feb 23, 2014 at 7:25 AM, Will Hobbs <Will.Hobbs@utas.edu.au<mailto:Will.Hobbs@utas.edu.au>> wrote:
Erika

Replace 'gsFillColor' with 'gsnXYBarChartColors'

Will
From: Erika Folova <e.folova@gmail.com<mailto:e.folova@gmail.com>>
Date: Sunday, 23 February 2014 9:17 AM
To: Will Hobbs <will.hobbs@utas.edu.au<mailto:will.hobbs@utas.edu.au>>
Cc: NCL-talk <ncl-talk@ucar.edu<mailto:ncl-talk@ucar.edu>>
Subject: Re: gsnXRefLine

Hi Will,

I have no Idea why I got this error: warning:gsFillColor is not a valid resource,
my plot resources are:

  res = True
  res@gsnDraw = False
  res@gsnFrame = False
  res@xyLineThicknesses = 2.0
  res@xyLineColors = "blue"
  ;res@xyMonoDashPattern = False
  res@gsnXYBarChart = True
  res@gsnXYBarChartOutlineOnly = True ;(even if i set this "False" still produced the same error)

  res@tmXBMode = "Explicit"
  res@tmXBValues = (/-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7/)
  res@tmXBLabels = (/-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7/)
  res@tmXMajorGrid = True
  res@tmXMajorGridThicknessF = 1.0 ; 2.0 is default
  res@tmXMajorGridLineDashPattern = 2 ; select short dash lines
  res@tmYMajorGrid = True ; implement y grid
  res@tmYMajorGridThicknessF = 1.0 ; 2.0 is default
  res@tmYMajorGridLineDashPattern = 2 ; select short dash lines

  res@gsnXRefLine = 0.0
  res@gsnXRefLineThicknessF = 3.0
  cols = where(yy.lt.0, "blue", "red")
  res@gsFillColor = cols

  plotD = gsn_csm_xy (wks, xx, yy, res)

Thank you Will,
Erika

On Sun, Feb 23, 2014 at 7:02 AM, Will Hobbs <Will.Hobbs@utas.edu.au<mailto:Will.Hobbs@utas.edu.au>> wrote:
Erika

Have you looked at the histogram examples on the NCL help files? There aren't any examples that do exactly what you want, but there should be enough there to pint you in the right direction

http://www.ncl.ucar.edu/Applications/histo.shtml

I can think of two ways of doing what you what. The first would be to plot values below zero and above zero separately with different colors (use the gsFillColor resource), and then overlay.

The second, probably easier way, would be to set up an array of fill colors the same size as the 'x' array.

> cols = where(xx.lt.0, "blue", "red") ; new array of size Nbin, where Nbin is the number of bins. Blue where xx is less than 0, red otherwise
> res@gsFillColor = cols

> plotD = gsn_csm_xy (wks, xx, yy, res)

Good luck

Will

From: Erika Folova <e.folova@gmail.com<mailto:e.folova@gmail.com>>
Date: Saturday, 22 February 2014 9:09 PM
To: NCL-talk <ncl-talk@ucar.edu<mailto:ncl-talk@ucar.edu>>
Subject: gsnXRefLine

NCL,

I am wondering whethere there is a function that works similar like res@gsnAboveYRefLineColor or res@gsnBelowYRefLineColor but for gsnXRefLine?
I would like to shade my histogram with gray for the value lower than zero:

e.g.

[SNIP]

res = True
  res@gsnDraw = False
  res@gsnFrame = False
  res@xyLineThicknesses = 2.0
  res@xyLineColors = "blue"
  res@xyMonoDashPattern = False ; all solid
  res@tiYAxisString = "PDF (%) "
  res@tiXAxisString = "PC "
  res@gsnXYBarChart = True ; Create bar plot
  ;res@gsnXYBarChartOutlineOnly = True

  res@trXMinF = -5.0 ; min value on y-axis
  res@trXMaxF = 7.0
  res@trYMinF = 0.0 ; min value on y-axis
  res@trYMaxF = 10.0
  res@vpHeightF= 0.3 ; change aspect ratio of plot
  res@vpWidthF = 0.90

  res@tmXBMode = "Explicit"
  res@tmXBValues = (/-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7/)
  res@tmXBLabels = (/-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7/)
  res@tmXMajorGrid = True
  res@tmXMajorGridThicknessF = 1.0 ; 2.0 is default
  res@tmXMajorGridLineDashPattern = 2 ; select short dash lines
  res@tmYMajorGrid = True ; implement y grid
  res@tmYMajorGridThicknessF = 1.0 ; 2.0 is default
  res@tmYMajorGridLineDashPattern = 2 ; select short dash lines

  res@vpXF = 0.07 ; position and size
  res@vpYF = 0.45

  res@tiMainFontHeightF = 0.018
  res@tmXBLabelFontHeightF = 0.014
  res@tmYLLabelFontHeightF = 0.014

  res@gsnXRefLine = 0.0
  res@gsnXRefLineThicknessF = 3.0
  res@gsnRightXRefLineColor = "red" ; above ref line fill red
  res@gsnLeftXRefLineColor = "blue"

  plotD = gsn_csm_xy (wks, xx, yy, res)

---
Thanks
Erika
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Received on Sat Feb 22 18:33:36 2014