How to make cpt and colorbar with time series?

Q&A
1

Dear All,

I am currently plotting some data points with respect to time series (as cpt) using GMT 6.1.1. I used this script, but it does not work. Any suggestions will be appreciated?

gmt makecpt -T2020-05-08T/2020-06-02T/5h > t.cpt    
#input format is like 104.4902 29.3797 2020-05-13T04:51:15

awk -F"," '{ print $8,$7,substr($3,1,length($3)-8)}'  $FI_result | gmt plot -Sc0.35c -Ct.cpt

But I got this error:

 plot [ERROR]: CPT t.cpt has no z-slices!
 [Session gmt (0)]: Error returned from GMT API: GMT_CPT_READ_ERROR (8)
 [Session gmt (0)]: Error returned from GMT API: GMT_CPT_READ_ERROR (8)

How can we make cpt using datetime and get the color bar respectively?

Thank you so much.

2

Not sure about the problem, but first step is to upgrade to 6.4.0 (or build latest).
6.1.1 is > 2 years old.

3

What’s the content of t.cpt after makecpt command ?

5

I have updated the script and now content are

2020-05-08T05:00:00	   52.187/27.562/82.312	  2020-05-08T10:00:00	52.187/27.562/82.312	L

But error is still the same.

6

I have converted the date into Julian days and made cpt. It works very well.

7

The command works well for me :

2020-05-08T00:00:00	50.062/21.187/67.437	2020-05-08T05:00:00	50.062/21.187/67.437	L
2020-05-08T05:00:00	52.187/27.562/82.312	2020-05-08T10:00:00	52.187/27.562/82.312	L
...
2020-06-01T09:00:00	139.94/9.3125/1.6875	2020-06-01T14:00:00	139.94/9.3125/1.6875	L
2020-06-01T14:00:00	133.56/7.1875/2	2020-06-01T19:00:00	133.56/7.1875/2L
2020-06-01T19:00:00	126.19/5.0624/2	2020-06-02T00:00:00	126.19/5.0624/2B
B	black
F	white
N	128

I use version 6.5