How can I import from Excel CSV

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EW
EW on 24 Nov 2020
Commented: Star Strider on 24 Nov 2020
I have a device that measures time and three other variables (X, Y, Z). The data always starts at row 24 but the end row is different for every file (in the case of the sample file it is row 33303). The device saves the data in a .csv file (attached)
I want to be able to create an app that will allow me to do the following
1) Browse and select the file
2) Import each variable (time, x, y, z) as a vector over the range (starting at row 24)
3) Analyze the data
I figured out step 1 and I have code for step 3 but I'm having trouble with the import over the specific file range. Either I can't get it to work or I'm able to only import part of the data.
Thanks!

Accepted Answer

Star Strider
Star Strider on 24 Nov 2020
Edited: Star Strider on 24 Nov 2020
Use readtable to read it:
T1 = readtable('sample.csv', 'VariableNamingRule','preserve', 'HeaderLines',22);
The 'Headerlines' name-value pair skips the first 22 lines, creating a useful table as ‘T1’.
To access the variables, see Access Data in Tables.
One slight complication is the first column, that requires a slight bit of effort, since the preserved variable names need to be in quotes and in parentheses:
time_ms = T1.('Time(ms)');
The others are straightforward to access:
X = T1.X;
and so for the rest.
Firefox chose to crash on me while I was writing this. My apologies for the delay.
EDIT — (24 Nov 2020 at 21:18)
In R2020a, it might be necesary to use 'PreserveVariableNames',1 instead. The result is the same, only the arguments are different.
  2 Comments
EW
EW on 24 Nov 2020
I copied and pasted your T1 code and it did not work. But I got it to work by removing the 'VariableNamingRule' and 'preserve'.
Many thanks. I'm alot further along than I was with this help!
Star Strider
Star Strider on 24 Nov 2020
As always, my pleasure!
Please note that I added the EDIT with respect to R2020a and earlier releases requiring a different name-value pair to achieve the same result.

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