Convert Columns Arrays to numeric

Hi,

I have a timetable with various data columns - I have imported these from an excel file. I need to make an addition to the all rows of colums and to add a column with the result. I think that my arrays are currently not numeric type and therefor I can not add them. Is there a way that I can convert data of columns 1-7 to numeric and make a summation? Or how can I know the data type of the columns?

[Andrei Bobrov]

Please attach here your variable 'combine' as mat-file

>> save('yourdata.mat','combine') % run in yur Command Window

And attach here file yourdata.mat .

Answer 1

[Andrei Bobrov]

...how can I know the data type of the columns?

varfun(@class,combine)

solution:

load('data.mat')

combine = [combine,rowfun(@funsum,combine,'OutputVariableName','SUM_ALL_kW')];

function out = funsum(varargin)
    out = sum([varargin{:}],2);
end

or

combine.SUM_ALL_kW = sum(combine{:,:},2) ;

[Andrei Bobrov]

Comment by Stefan Azzopardi:

Andrei, Thanks for your help and it worked perfectly. This resulted in a new column with the sum of the other columns. Thank you once again for your help :) :)

[Andrei Bobrov]

Stefan! If my answer solved your problem, then please accept it.

Answer 2

[WalterWhite]

t = datetime('now')

nn = datenum(t)+10;

f= datetime(nn,'ConvertFrom','datenum')

>> reading

t =

datetime

15-Jan-2020 09:52:43

f =

datetime

25-Jan-2020 09:52:43

did you mean something like this?

[Stefan Azzopardi]

thank you for your help Walter, but it is not exactly what I meant. Anyway, I got all the help that I requested from Andrei :) :)

Answer 3

[Steven Lord]

Using the example from the timetable help text:

MeasurementTime = datetime({'2015-12-18 08:03:05';'2015-12-18 10:03:17';'2015-12-18 12:03:13'});
Temp = [37.3;39.1;42.3];
Pressure = [30.1;30.03;29.9];
WindSpeed = [13.4;6.5;7.3];
WindDirection = categorical({'NW';'N';'NW'});
TT = timetable(MeasurementTime,Temp,Pressure,WindSpeed,WindDirection)

Let's say that I wanted (for whatever reason) to add the temperature, pressure, and wind speed. I can extract that data from TT into a numeric array in two different ways:

A1 = TT{:, ["Temp", "Pressure", "WindSpeed"]} % Using variable names
A2 = TT{:, 1:3} % Using variable numbers

Now sum and put back into TT.

TT.combinedData = sum(A1, 2)

If all your data could be concatenated into an array with a uniform type, you could extract the data even easier. But this technique won't work for TT, as you can't combine a numeric variable like TT.Temp and a categorical variable like TT.WindDirection into one array.

TT.Variables