MATLAB: How can i create a descriptive statistics table for columns

descreptivemeanstatistics

Hey Guys!

My MatLab skills are pretty pretty basic and now i need your help with something, because i can't find the answer here. So i have a 15×10 data.mat where there are 10 variables with 15 values. Now i want some descreptive statistics of those variables.

The perfect solution would be a group that looks kind of like this:

            Mean  Max  Std  ...
Variable 1   x     x    x
Variable 2   x     x    x 
...

Is there any way to achieve a table/group like this?

Thank you very much in advance!

Best Answer

The default behavior for most of the statistical function is for column-wise operation and since that is what you want you can just apply them to your data matrix. So, if you want to collate the results together in a matrix:

results=[mean(data)' max(data)' std(data)']

If you specically want a table then:

dummyData=randi(10,15,10)
results=table()
results.Mean=mean(dummyData)'
results.Max=max(dummyData)'
results.Std_dev=std(dummyData)'

results =

10×3 table
     Mean     Max    Std_dev
    ______    ___    _______
       5.6    10     3.4184 
    5.0667     9     2.7894 
    4.6667    10     3.2878 
    6.0667    10     2.7894 
       5.2    10     2.8082 
    5.0667    10     2.5765 
         5    10     2.9032 
       5.6    10     2.7464 
    5.5333    10     2.8502 
       5.2     9     2.5967

Related Solutions

MATLAB: Devide a table in several tables by criteria

You can do this in several ways, but honestly the most straight-forward is to write a loop, as shown below. The real question is, why do you want to do this? I'm genuinely asking, because there are tools that let you do things like hourly means without splitting the data up. I guess your answer would be, "I want to plot things separately". Fair enough: you can trick rowfun into doing that but it's a little tricky. Are there other things you want to do on the separate timetables?

Anyways, my solution (which could certainly be tightened up but is at least clear):

>> tt = timetable(rand(15,1),[1;1;1;0;0;1;1;1;1;0;1;1;1;1;1], ...
    'RowTimes',datetime(2019,6,19,0,0,0:14), ...
    'VariableNames',{'X' 'OnOff'});
>> tt.Group = 1 + [0; cumsum(diff([tt.OnOff])~=0)]
tt =
  15×3 timetable
            Time               X        OnOff    Group
    ____________________    ________    _____    _____
    19-Jun-2019 00:00:00     0.69989      1        1  
    19-Jun-2019 00:00:01     0.63853      1        1  
    19-Jun-2019 00:00:02    0.033604      1        1  
    19-Jun-2019 00:00:03    0.068806      0        2  
    19-Jun-2019 00:00:04      0.3196      0        2  
    19-Jun-2019 00:00:05     0.53086      1        3  
    19-Jun-2019 00:00:06     0.65445      1        3  
    19-Jun-2019 00:00:07     0.40762      1        3  
    19-Jun-2019 00:00:08     0.81998      1        3  
    19-Jun-2019 00:00:09     0.71836      0        4  
    19-Jun-2019 00:00:10     0.96865      1        5  
    19-Jun-2019 00:00:11     0.53133      1        5  
    19-Jun-2019 00:00:12     0.32515      1        5  
    19-Jun-2019 00:00:13     0.10563      1        5  
    19-Jun-2019 00:00:14     0.61096      1        5  
>> c = cell(numel(unique(tt.Group)),1);
>> for i = 1:length(c), c{i} = tt(tt.Group == i,1:2); end
>> c{:}
ans =
  3×2 timetable
            Time               X        OnOff
    ____________________    ________    _____
    19-Jun-2019 00:00:00     0.69989      1  
    19-Jun-2019 00:00:01     0.63853      1  
    19-Jun-2019 00:00:02    0.033604      1  
ans =
  2×2 timetable
            Time               X        OnOff
    ____________________    ________    _____
    19-Jun-2019 00:00:03    0.068806      0  
    19-Jun-2019 00:00:04      0.3196      0  
ans =
  4×2 timetable
            Time               X       OnOff
    ____________________    _______    _____
    19-Jun-2019 00:00:05    0.53086      1  
    19-Jun-2019 00:00:06    0.65445      1  
    19-Jun-2019 00:00:07    0.40762      1  
    19-Jun-2019 00:00:08    0.81998      1  
ans =
  1×2 timetable
            Time               X       OnOff
    ____________________    _______    _____
    19-Jun-2019 00:00:09    0.71836      0  
ans =
  5×2 timetable
            Time               X       OnOff
    ____________________    _______    _____
    19-Jun-2019 00:00:10    0.96865      1  
    19-Jun-2019 00:00:11    0.53133      1  
    19-Jun-2019 00:00:12    0.32515      1  
    19-Jun-2019 00:00:13    0.10563      1  
    19-Jun-2019 00:00:14    0.61096      1

MATLAB: How to create a matrix, table or a cell where in odd columns variables from matrix A and in even columns variabls from matrix B will be stored

This should work for numeric, cell and table, although Adam's is likely more efficient for numeric:

>> x1 = array2table(rand(3))
x1 =
  3×3 table
     Var1        Var2       Var3  
    _______    ________    _______
    0.77917     0.56882    0.33712
    0.93401     0.46939    0.16218
    0.12991    0.011902    0.79428
>> x2 = array2table(randn(3),'VariableNames',{'Var4' 'Var5' 'Var6'})
x2 =
  3×3 table
      Var4        Var5        Var6  
    ________    ________    ________
    -0.88803     0.30352     0.73936
     0.10009    -0.60033      1.7119
    -0.54453     0.48997    -0.19412
>> x = [x1 x2]
x =
  3×6 table
     Var1        Var2       Var3        Var4        Var5        Var6  
    _______    ________    _______    ________    ________    ________
    0.77917     0.56882    0.33712    -0.88803     0.30352     0.73936
    0.93401     0.46939    0.16218     0.10009    -0.60033      1.7119
    0.12991    0.011902    0.79428    -0.54453     0.48997    -0.19412
>> x = x(:,[(1:3)+[0;3]]) % requires 16b or later, otherwise use bsxfun
x =
  3×6 table
     Var1        Var4        Var2        Var5       Var3        Var6  
    _______    ________    ________    ________    _______    ________
    0.77917    -0.88803     0.56882     0.30352    0.33712     0.73936
    0.93401     0.10009     0.46939    -0.60033    0.16218      1.7119
    0.12991    -0.54453    0.011902     0.48997    0.79428    -0.19412

Best Answer

Related Solutions

MATLAB: Devide a table in several tables by criteria

MATLAB: How to create a matrix, table or a cell where in odd columns variables from matrix A and in even columns variabls from matrix B will be stored

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