add a vector as a timetable element

Hi,

I would like to write the column of a matrix as element of a timetable (meaning a column for each time). in this timetable I have other variables that have a scalar value at each time. Any suggestion on how to do it?

Cheers,

Giacomo

Answer 1

[Cris LaPierre]

A column for each time? Do you mean row?

Just add it as a new variable in your timetable. Each column is typically a separate variable.

indoors = readtimetable('indoors.csv')

indoors = 60x2 timetable
           Time            Humidity    AirQuality
    ___________________    ________    __________

    2015-11-15 00:00:24       36           80    
    2015-11-15 01:13:35       36           80    
    2015-11-15 02:26:47       37           79    
    2015-11-15 03:39:59       37           82    
    2015-11-15 04:53:11       36           80    
    2015-11-15 06:06:23       36           80    
    2015-11-15 07:19:35       36           80    
    2015-11-15 08:32:47       37           80    
    2015-11-15 09:45:59       37           79    
    2015-11-15 10:59:11       36           80    
    2015-11-15 12:12:23       37           80    
    2015-11-15 13:25:35       37           79    
    2015-11-15 14:38:46       36           83    
    2015-11-15 15:51:58       37           80    
    2015-11-15 17:05:10       36           80    
    2015-11-15 18:18:22       37           80    

% Create temperatures
tempF = randi(100,[height(indoors),1]);
% Add vector of temperatures to timetable
indoors.Temp = tempF

indoors = 60x3 timetable
           Time            Humidity    AirQuality    Temp
    ___________________    ________    __________    ____

    2015-11-15 00:00:24       36           80         75 
    2015-11-15 01:13:35       36           80         17 
    2015-11-15 02:26:47       37           79          6 
    2015-11-15 03:39:59       37           82         92 
    2015-11-15 04:53:11       36           80         74 
    2015-11-15 06:06:23       36           80         98 
    2015-11-15 07:19:35       36           80         72 
    2015-11-15 08:32:47       37           80         65 
    2015-11-15 09:45:59       37           79          1 
    2015-11-15 10:59:11       36           80         84 
    2015-11-15 12:12:23       37           80         45 
    2015-11-15 13:25:35       37           79         23 
    2015-11-15 14:38:46       36           83         65 
    2015-11-15 15:51:58       37           80          5 
    2015-11-15 17:05:10       36           80         46 
    2015-11-15 18:18:22       37           80         10 

[giacomo labbri]

Thanks for you detail answer but this is not what I am trying to do. Referring to the example:

I would like to add for each time in the initial time table a vector that is the temperature at different heights (and this are stored in a matrix in which each column correspond to a time, this is why I said column but it is not the central part of the problem).

So my table (using your example) would have for each time one value of humidity, one value of air quality and a vector that is the temperature at - lets say 10 - different heights.

This temperatures are stored into a matrix that has a column for each time and a row for each height (so in the example 10 rows and 60 colums).

Hope I managed to explained myself.

Thanks again!

Giacomo

[Cris LaPierre]

Still not a problem. Can we assume the times in your timtable rows align with the times of your matrix colums?

Updating the example slightly.

% Creating a 60x2 timetable
indoors = readtimetable('indoors.csv');

% Creating a matrix with 4 heights x 60 times (reduced for visual purposes only)
tempF = randi(100,[4,60]);

% Add temps to timetable under a variable Temp
% Transopose tempF so that rows are times, and columns are heights
indoors.Temp = tempF'

indoors = 60x3 timetable
           Time            Humidity    AirQuality             Temp          
    ___________________    ________    __________    _______________________

    2015-11-15 00:00:24       36           80         4     16     47     59
    2015-11-15 01:13:35       36           80        23      3     13     91
    2015-11-15 02:26:47       37           79        76     34     90     13
    2015-11-15 03:39:59       37           82        76     24     12     41
    2015-11-15 04:53:11       36           80        92     76     25     39
    2015-11-15 06:06:23       36           80        67     85     37     63
    2015-11-15 07:19:35       36           80        20      4     29     68
    2015-11-15 08:32:47       37           80        41     60     98     99
    2015-11-15 09:45:59       37           79        64     48     15     14
    2015-11-15 10:59:11       36           80        56     26    100     31
    2015-11-15 12:12:23       37           80        67     74     55     74
    2015-11-15 13:25:35       37           79        57      2     46     16
    2015-11-15 14:38:46       36           83        84     54     16     35
    2015-11-15 15:51:58       37           80        87     21     12     23
    2015-11-15 17:05:10       36           80        61     73     34     78
    2015-11-15 18:18:22       37           80        69     81     66     73

If you want each height to be its own variable, you can use the splitvars function.

indoors = splitvars(indoors,'Temp','NewVariableNames',["H1" "H2" "H3" "H4"])

indoors = 60x6 timetable
           Time            Humidity    AirQuality    H1    H2    H3     H4
    ___________________    ________    __________    __    __    ___    __

    2015-11-15 00:00:24       36           80         4    16     47    59
    2015-11-15 01:13:35       36           80        23     3     13    91
    2015-11-15 02:26:47       37           79        76    34     90    13
    2015-11-15 03:39:59       37           82        76    24     12    41
    2015-11-15 04:53:11       36           80        92    76     25    39
    2015-11-15 06:06:23       36           80        67    85     37    63
    2015-11-15 07:19:35       36           80        20     4     29    68
    2015-11-15 08:32:47       37           80        41    60     98    99
    2015-11-15 09:45:59       37           79        64    48     15    14
    2015-11-15 10:59:11       36           80        56    26    100    31
    2015-11-15 12:12:23       37           80        67    74     55    74
    2015-11-15 13:25:35       37           79        57     2     46    16
    2015-11-15 14:38:46       36           83        84    54     16    35
    2015-11-15 15:51:58       37           80        87    21     12    23
    2015-11-15 17:05:10       36           80        61    73     34    78
    2015-11-15 18:18:22       37           80        69    81     66    73

If you need help in accessing your data in the table, see this documentation page.

[giacomo labbri]

Thanks! This was very helpful!