Plot two data into the same graph (Field) - Raspberry Pi

Plot two data into the same graph (Field) - Raspberry Pi

August 19, 2018
5:06 am

Nano

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August 19, 2018

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I connected a sensor to capture (volt and current across a component) to a raspberry pi, and I wanna plot an IV curve.
in my code, I'm running a sweep to capture those data, my code works just fine and I can plot the IV curve on my GUI by using matplotlib.
In addition to my project, I wanna display/plot the IV curve online. Then I thought of using Thingspeak for this matter, but I noticed that it can only plots one data against time/date.
Is there anyway that I can plot two data on one graph and neglect the time?

Note that the data I'm sending to my Thingspeak channel are two variables i and v which each one has 14 values.

screenshots:
- data exported from Thingspeak
- commands used in python

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August 21, 2018
8:36 am

cstapels

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March 7, 2017

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Here is a two axis plot example without time on the independant axis: https://www.mathworks.com/help/thingspeak/Visualize-Correlation-Between-Temperature-and-Humidity.html

You can also use the MATLAB plot() or scatter() functions, they have different options.

Your data format is not in the standard arrangement - do you intend each entry to be a new IV sweep?

You can read the data
dataTable=thingSpeakRead(CHID,'outputformat','timeTable','readkey','xxxxxxxxxxxxxxxx'...)
then use str2num and char to get the values.
vectorX=str2num(char(dataTable.Field1Label));
Repeat for both field 1 and 2.

Then you can plot() or thingSpeakScatter(vectorX,vectorY, etc.)

Let us know if that works.

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