[ncl-talk] Fewer questions about a Histogram Plot

[Mary Haley]

Barry,

You don't want to use discrete bin intervals, unless you are wanting to
count the # of values *exactly equal* to a value.

For a range of values, use gsnHistogramBinIntervals.

Please read over the histogram page carefully, because we have many
examples on this page that talk about the different histogram options.

As I think I mentioned before, I updated example histo_2.ncl to show how to
explicitly request an array of bin intervals.

Run the attached script, will hopefully illustrate the difference between
gsnHistogramBinIntervals and gsnHistogramDiscreteBinValues.

--Mary


On Mon, Nov 20, 2017 at 8:54 AM, Barry Lynn <barry.h.lynn at gmail.com> wrote:

> Hello:
>
> I found the coding lines that allows me to map the number of intervals,
> explicitly.  I found the coding lines that allow me to specify how many of
> the labels I want to map.
>
> That's here:
>
> https://www.ncl.ucar.edu/Applications/Scripts/histo_3.ncl
>
>  res at tmXBLabelStride                = 2     ; every other x-label
>   res at gsnHistogramDiscreteBinValues  = ispan(0,25,1)
>
> However, I don't see how to change the number of labels to be different
> from their default number, which equals the number of tmXBValues.
>
> I need to set the latter so that I can add more than 9 labels.
>
> Thank you
>
>
> (0) res at tmXBLabels = -9
>
> (1) res at tmXBLabels = 0
>
> (2) res at tmXBLabels = 9
>
> (3) res at tmXBLabels = 18
>
> (4) res at tmXBLabels = 27
>
> (5) res at tmXBLabels = 36
>
> (6) res at tmXBLabels = 45
>
> (7) res at tmXBLabels = 54
>
> (8) res at tmXBLabels = 63
>
> (0) tmXBValues = 0.0555556
>
> (1) tmXBValues = 0.166667
>
> (2) tmXBValues = 0.277778
>
> (3) tmXBValues = 0.388889
>
> (4) tmXBValues = 0.5
>
> (5) tmXBValues = 0.611111
>
> (6) tmXBValues = 0.722222
>
> (7) tmXBValues = 0.833333
>
> (8) tmXBValues = 0.944444
>
> On Mon, Nov 20, 2017 at 3:01 PM, Barry Lynn <barry.h.lynn at gmail.com>
> wrote:
>
>> Hi:
>>
>> I can get the labels to display correctly if I use:
>>
>> res at tmXBLabels = int_radar(::3)
>>
>>
>> However, the histogram program is amalgamating the smaller bins into 10
>> sized default bins.
>>
>>
>> I would hope that there is a way to explicitly tell the histogram program
>> to use all the interval data (23 intervals.
>>
>>
>> I tried setting:
>>
>>
>> res at tmXBMode        = "Manual"
>>
>> and creating manual tick marks, but then my histogram labels go only from
>> 0 to 1.
>>
>>
>> As below.
>>
>>
>>  rad_inc = 3./(int_radar(dimsizes(int_radar)-1)+10)
>>
>>   print("rad_inc  = " +rad_inc)
>>
>>   new_ticks = new(dimsizes(int_radar),float)
>>
>>   new_ticks(0)= 0
>>
>>   do inc = 1,dimsizes(int_radar)-1,1
>>
>>    new_ticks(inc) = new_ticks(inc-1)+rad_inc
>>
>>   end do
>>
>>   print("new_ticks = " + new_ticks)
>>
>>   res at tmXBValues := new_ticks
>>
>>   res at tmXBLabels := int_radar
>>
>> On Sun, Nov 19, 2017 at 9:21 PM, Barry Lynn <barry.h.lynn at gmail.com>
>> wrote:
>>
>>> Hi:
>>>
>>> I am having trouble figuring out why my histo.ncl program won't plot
>>> data beyond value (x-axis) of 15.  This is really dbz data, so the range is
>>> correct: -9 to 60.
>>>
>>> I also checked that the labels are present in:
>>>
>>> res at tmXBLabels = int_radar
>>>
>>>
>>> and the data dimensions are correct (23 elements).
>>>
>>> However, I don't see any data (and any labels 18-60) indicating that the
>>> data has all been displayed.
>>>
>>> Thank you,
>>>
>>> Barry
>>>
>>> --
>>> Barry H. Lynn, Ph.D
>>> Senior Lecturer,
>>> The Institute of the Earth Science,
>>> The Hebrew University of Jerusalem,
>>> Givat Ram, Jerusalem 91904, Israel
>>> Tel: 972 547 231 170
>>> Fax: (972)-25662581
>>>
>>> C.E.O, Weather It Is, LTD
>>> Weather and Climate Focus
>>> http://weather-it-is.com
>>> Jerusalem, Israel
>>> Local: 02 930 9525
>>> Cell: 054 7 231 170
>>> Int-IS: x972 2 930 9525
>>> US 914 432 3108 <(914)%20432-3108>
>>>
>>
>>
>>
>> --
>> Barry H. Lynn, Ph.D
>> Senior Lecturer,
>> The Institute of the Earth Science,
>> The Hebrew University of Jerusalem,
>> Givat Ram, Jerusalem 91904, Israel
>> Tel: 972 547 231 170
>> Fax: (972)-25662581
>>
>> C.E.O, Weather It Is, LTD
>> Weather and Climate Focus
>> http://weather-it-is.com
>> Jerusalem, Israel
>> Local: 02 930 9525
>> Cell: 054 7 231 170
>> Int-IS: x972 2 930 9525
>> US 914 432 3108 <(914)%20432-3108>
>>
>
>
>
> --
> Barry H. Lynn, Ph.D
> Senior Lecturer,
> The Institute of the Earth Science,
> The Hebrew University of Jerusalem,
> Givat Ram, Jerusalem 91904, Israel
> Tel: 972 547 231 170
> Fax: (972)-25662581
>
> C.E.O, Weather It Is, LTD
> Weather and Climate Focus
> http://weather-it-is.com
> Jerusalem, Israel
> Local: 02 930 9525
> Cell: 054 7 231 170
> Int-IS: x972 2 930 9525
> US 914 432 3108 <(914)%20432-3108>
>
> _______________________________________________
> ncl-talk mailing list
> ncl-talk at ucar.edu
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20171120/1c631fe4/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: histo_mod.ncl
Type: application/octet-stream
Size: 1179 bytes
Desc: not available
URL: <http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20171120/1c631fe4/attachment.obj>