[ncl-talk] Creating heatmap (Month/day vs. Year) in NCL

[Dennis Shea]

re:
"Has anyone tried to plot a heatmap using NCL or is this possible to do in
NCL?"

Your use if the term 'heatmap' is misleading. Anomalies (W/m2) are being
plotted. However, the values could be anything .. not necessarily 'heat'.

Given that the y-axis is 'YEAR' and the x-axis is 'day', a more appropriate
classification would be a 'time-time' (year-day) plot.

---
re: "Is this possible to do in NCL?"

Yes, of course NCL can do it. Likely any tool could be used.
Actually, the plot looks like an NCAR Graphics plot.
---
re: "the sample data"

The sample data file contains *monthly* precipitation. This* can not *be
used to create the *daily* plot you attached. You *must *use daily data.
---
re: attached plot

This looks like colored anomalies were plotted and, the then another
variable was overlaid.

[1] read daily data
[2] create daily climatology
[3] calculate daily anomalies
[4] for each year; extract the days spanning 15 May through 15 July
[5] populate the array with the values for [4]
[6] add appropriate meat data
[7] plot a contour map; no overlays were performed.

NCL has the climatology functions and date functions necessary to create a
'time-time plot. However, most of the work is book-keeping.

===
The area you are using is so 'small' that simple averaging is adequate.

===
I had an existing code that uses daily OLR values to compute daily
climatologies and anomalies.  I added many comments and print statement.
Please look carefully.

Many comments point to the documentation for the functions being used.
Again, please read.

The figures show how to change the x-axis (day/month-day) labels

Good luck




On Tue, Aug 8, 2017 at 10:37 PM, Lyndon Mark Olaguera <
olagueralyndonmark429 at gmail.com> wrote:

> Dear NCL experts,
>
> Has anyone tried to plot a heatmap using NCL or is this possible to do in
> NCL?
>
> I am trying to plot month-day versus year plot similar to the attached
> figure.
>
> I want to apply this on an area averaged time series (here's the link to
> the sample data)
> https://www.dropbox.com/s/0jax40zbr231sdu/cmap.nc?dl=0
>
>
> I'll appreciate if anyone can point me in the right functions to create
> this.
>
> Thank you in advance.
>
> Sincerely,
>
> Lyndz
>
> _______________________________________________
> 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/20170809/9c9d57d6/attachment-0001.html 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: dayYear.ncl
Type: application/octet-stream
Size: 5747 bytes
Desc: not available
Url : http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20170809/9c9d57d6/attachment-0001.obj 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: DayYear.olr.000001.png
Type: image/png
Size: 873318 bytes
Desc: not available
Url : http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20170809/9c9d57d6/attachment-0002.png 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: DayYear.olr.000002.png
Type: image/png
Size: 857637 bytes
Desc: not available
Url : http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20170809/9c9d57d6/attachment-0003.png