Transform data from long to wide format

Hi community,

My data is currently in long format (data_long.csv) and I am trying to convert it to wide format (data_wide.csv).

I have 15 participants and 16 variables to do this for. Any tips would be great!

Thank you,

Danielle

Answer 1

[Star Strider]

Use unstack, preferably the same unstack call with the same MATLAB version that produced the ‘data_wide’ file.

Experiment with it, since I cannot get the same result.

L1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1062580/data_long.csv')

L1 = 6×5 table
    P    Demo    Time    Con     Var1  
    _    ____    ____    ___    _______

    1     1       1       1     0.11974
    1     1       1       2     0.58441
    1     1       2       1     0.79951
    1     1       2       2     0.23271
    1     1       3       1     0.53867
    1     1       3       2     0.03069

W1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1062585/data_wide.csv')

W1 = 1×8 table
    P    Demo    Var1_Time1_Con1    Var1_Time1_Con2    Var1_Time2_Con1    Var1_Time2_Con2    Var1_Time3_Con1    Var1_Time3_Con2
    _    ____    _______________    _______________    _______________    _______________    _______________    _______________

    1     1          0.11974            0.58441            0.79951            0.23271            0.53867            0.03069    

L1toW2 = unstack(L1,{'Var1','Time'},'Con')

Warning: Table variable names that were not valid MATLAB identifiers have been modified. Since table variable names must be unique, any table variable names that happened to match the new identifiers also have been modified.
To use the original INDVAR values as table variable names, set 'VariableNamingRule' to 'preserve'.

L1toW2 = 1×6 table
    P    Demo    Var1_x1    Var1_x2    Time_x1    Time_x2
    _    ____    _______    _______    _______    _______

    1     1      1.4579     0.84781       6          6   

.

[Danielle Vickery-Howe]

Hi Star Strider, thank you for your response!

I think I need to be able to unstack my data twice?

I can unstack one grouping variable, but I can't manage to unstack for the second.

I think the only way is going to be able to unstack Con by 'x1' 'x2' 'x3'. But I have not yet figured how to do this.

L1 = readtable("data_long.csv");

W1 = readtable("data_wide.csv");

TimeWide = unstack(L1,'Var1','Time')

Warning: Table variable names that were not valid MATLAB

identifiers have been modified. Since table variable names

must be unique, any table variable names that happened to

match the new identifiers also have been modified.

To use the original INDVAR values as table variable names, set

'VariableNamingRule' to 'preserve'.

TimeWide =

2×6 table

P Demo Con x1 x2 x3

_ ____ ___ _______ _______ _______

1 1 1 0.11974 0.79951 0.53867

1 1 2 0.58441 0.23271 0.03069

[Star Strider]

It depends on wthe result you want. I used two grouping variables and it seemed to work (R2022a). The result provided seems to have changed over the last few versions. You will likely have to experiment with it.