calculate the mean value if the numbers are same

Hello,

I just learn matlab, so not very familiar with it.

I just want to calculate the mean value if the first column numbers are same:

Thanks in advance!

yue

Input is:

 2  0.99  0.15  0.60  0.12  0.76  0.16  0.81  0.02  0.75  0.32
 2  0.17  0.38  0.34  0.02  0.74  0.67  0.75  0.92  0.23  0.81
 2  0.26  0.16  0.30  0.29  0.74  0.89  0.12  0.65  0.06  0.79
 3  0.40  0.76  0.45  0.32  0.11  0.52  0.53  0.93  0.77  0.85
 3  0.07  0.87  0.42  0.65  0.68  0.70  0.33  0.16  0.67  0.51
 3  0.68  0.35  0.36  0.96  0.46  0.15  0.55  0.92  0.72  0.64
 3  0.40  0.69  0.56  0.94  0.21  0.95  0.40  0.79  0.64  0.95
 4  0.98  0.29  0.74  0.46  0.10  0.54  0.42  0.58  0.42  0.44
 4  0.40  0.53  0.42  0.24  0.82  0.68  0.18  0.44  0.39  0.06
 4  0.62  0.83  0.43  0.76  0.18  0.04  0.26  0.26  0.82  0.87

Output is:

 2  0.47  0.23  0.41  0.15  0.75  0.57  0.56  0.53  0.35  0.64
 3  0.39  0.67  0.45  0.72  0.37  0.58  0.45  0.70  0.70  0.74
 4  0.67  0.55  0.53  0.49  0.37  0.42  0.28  0.43  0.54  0.46

Answer 1

[Star Strider]

One option:

M = [ 2  0.99  0.15  0.60  0.12  0.76  0.16  0.81  0.02  0.75  0.32
    2  0.17  0.38  0.34  0.02  0.74  0.67  0.75  0.92  0.23  0.81
    2  0.26  0.16  0.30  0.29  0.74  0.89  0.12  0.65  0.06  0.79
    3  0.40  0.76  0.45  0.32  0.11  0.52  0.53  0.93  0.77  0.85
    3  0.07  0.87  0.42  0.65  0.68  0.70  0.33  0.16  0.67  0.51
    3  0.68  0.35  0.36  0.96  0.46  0.15  0.55  0.92  0.72  0.64
    3  0.40  0.69  0.56  0.94  0.21  0.95  0.40  0.79  0.64  0.95
    4  0.98  0.29  0.74  0.46  0.10  0.54  0.42  0.58  0.42  0.44
    4  0.40  0.53  0.42  0.24  0.82  0.68  0.18  0.44  0.39  0.06
    4  0.62  0.83  0.43  0.76  0.18  0.04  0.26  0.26  0.82  0.87];

G = findgroups(M(:,1));
Out = [unique(M(:,1)) splitapply(@mean, M(:,2:end), G)]

[yue li]

Hello, Star strider,

Thank you so much for your great help!

Yue

[Star Strider]

Hello Yue Li,

As always, my pleasure!

Star Strider