How do i calculate the standard deviation from multiple csv files where i would like the standard deviation for each second?

This is what one of my many csv files look like, i would like to get the standard deviation for the temperatures at the different depths (0,2 and 4 mm) for each second. Thanks in advance!

[Matlab Pro]

Hi @axel.

Few unclear issues:

• So you need a Matlab-Excel automation to fullfille this?
• Which exect Ecel function you want to use for the columns? (i.e. "STDEV.S" = "Estimates standard deviation based on a sample (ignores logical values and text in the sample")).
• So- the outcome for every CSV processed is a vector of the length of # of columns, each value = std of theat column. Correct?

[axel]

I have now complied the many csv files down to three files, each for the temperature over time at each specific depth (0,2 and 4mm). I have attached a photo of one of these said files. the 5.7,5.7.2, etc is refering to the sample number.

I am wondering if it is possible to calculate the standard deviation in MATLAB and not in excel. If this is rather complicated i can use excel however, I am more inclined to trust MATLAB than excel.

Thanks again in advance!

Answer 1

[Star Strider]

Perhaps this —

Time = datetime('now')+seconds(0:2).';
Time.Format = 'H:mm:ss';
Temperature = [20.754 19.219 19.338 20.89; 20.75 19.186 19.323 20.882; 20.784 19.186 19.312 20.857];
T1 = array2table(Temperature);
T1 = addvars(T1, Time, Before=1);
T1.Properties.VariableNames={'Time (Seconds)','(2mm_1)','(0mm)','(4mm)','(2mm_2)'}

T1 = 3x5 table
    Time (Seconds)    (2mm_1)    (0mm)     (4mm)     (2mm_2)
    ______________    _______    ______    ______    _______

       11:07:49       20.754     19.219    19.338     20.89 
       11:07:50        20.75     19.186    19.323    20.882 
       11:07:51       20.784     19.186    19.312    20.857 

T1.StdDev = std(T1{:,2:end},[],2)

T1 = 3x6 table
    Time (Seconds)    (2mm_1)    (0mm)     (4mm)     (2mm_2)    StdDev 
    ______________    _______    ______    ______    _______    _______

       11:07:49       20.754     19.219    19.338     20.89     0.89419
       11:07:50        20.75     19.186    19.323    20.882     0.90487
       11:07:51       20.784     19.186    19.312    20.857     0.90925

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EDIT — (30 Jan 2024 at 11:18)

With respect to the different files, see Import or Export a Sequence of Files.

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