Extract sensorvalues from string with units

Hello,

I got some CSV files with sensorvalues in it. I used the command 'readtable' to get the data into a Matlab table. It is now a 1440x2 table. In the first variable of the table is a timestamp that works fine, when i try to plot it. But in the second variable i got this format: {'29.6 °C'}. I know when i want to plot the second variable, i have to seperate the value from the unit and convert the value into a number, because i think it is saved as a string. But i can't find a fitting command. Does anyone has an idea how to seperate the values and how to plot them?

Below is a part of the table so you can get a better understanding of my problem.

Var1 Var2

___________________ ___________

2022-06-17 00:00:00 {'28.1 °C'}

2022-06-17 00:01:00 {'28 °C' }

2022-06-17 00:02:00 {'28 °C' }

2022-06-17 00:03:00 {'28 °C' }

2022-06-17 00:04:00 {'28 °C' }

[Joey]

Thanks a lot, that worked for me!

Best Regards

Joel

[Star Strider]

As always, my pleasure!

Answer 1

[Star Strider]

See the documentation section on Remove Prefix or Suffix Characters From Variables —

type('Test 2020 06 28.csv')                                 % Original File

    2022-06-17 00:00:00,          28.1 °C
    2022-06-17 00:01:00,          28 °C
    2022-06-17 00:02:00,          28 °C
    2022-06-17 00:03:00,          28 °C
    2022-06-17 00:04:00,          28 °C

opts = detectImportOptions('Test 2020 06 28.csv');
opts = setvartype(opts, 'Var2','double');
opts = setvaropts(opts, 'Var2','Suffixes','°C');
T1 = readtable('Test 2020 06 28.csv', opts)

T1 = 5×2 table
           Var1            Var2
    ___________________    ____

    2022-06-17 00:00:00    28.1
    2022-06-17 00:01:00      28
    2022-06-17 00:02:00      28
    2022-06-17 00:03:00      28
    2022-06-17 00:04:00      28

figure
plot(T1{:,1}, T1{:,2})
grid
ylim([27 29])                                               % Change As Necessary For Your Data

That appears to have imported my test file correctly.

EDIT — (28 Jun 2022 at 17:52)

Forgot the plot initially. Added it now.

.