How can I extract a specific time for a "datetime" table?

Dear coders,

I have a simple question but I am confused how to code it. I have this datetime table (attached with the question: RESULT.mat) and I want to keep only those rows that contains time between 2:00-3:00 am and 12:00-13:00 pm. As shown in this picture -

The final datetime table should contain only these rows with the desired HourSeries. Any feedback from you will be highly appreciated! <3

Answer 1

[Kevin Holly]

load('RESULT.mat')
result

result = 16282×3 table
    TimeSeries     HourSeries    HeightSeries
    ___________    __________    ____________

    10-Jan-2004    {'00:00'}         0.707   
    10-Jan-2004    {'01:00'}         0.997   
    10-Jan-2004    {'02:00'}         1.171   
    10-Jan-2004    {'03:00'}         1.134   
    10-Jan-2004    {'04:00'}         0.893   
    10-Jan-2004    {'05:00'}         0.557   
    10-Jan-2004    {'06:00'}         0.233   
    10-Jan-2004    {'07:00'}             0   
    10-Jan-2004    {'07:30'}       -0.0215   
    10-Jan-2004    {'08:00'}        -0.043   
    10-Jan-2004    {'09:00'}         0.116   
    10-Jan-2004    {'10:00'}         0.346   
    10-Jan-2004    {'11:00'}         0.562   
    10-Jan-2004    {'12:00'}         0.808   
    10-Jan-2004    {'13:00'}         1.084   
    10-Jan-2004    {'14:00'}         1.282   

result.HourSeries = datetime(result.HourSeries,"Format","HH:mm")

result = 16282×3 table
    TimeSeries     HourSeries    HeightSeries
    ___________    __________    ____________

    10-Jan-2004      00:00           0.707   
    10-Jan-2004      01:00           0.997   
    10-Jan-2004      02:00           1.171   
    10-Jan-2004      03:00           1.134   
    10-Jan-2004      04:00           0.893   
    10-Jan-2004      05:00           0.557   
    10-Jan-2004      06:00           0.233   
    10-Jan-2004      07:00               0   
    10-Jan-2004      07:30         -0.0215   
    10-Jan-2004      08:00          -0.043   
    10-Jan-2004      09:00           0.116   
    10-Jan-2004      10:00           0.346   
    10-Jan-2004      11:00           0.562   
    10-Jan-2004      12:00           0.808   
    10-Jan-2004      13:00           1.084   
    10-Jan-2004      14:00           1.282   

index = hour(result.HourSeries)==12|hour(result.HourSeries)==2;
result(index,:)

ans = 1305×3 table
    TimeSeries     HourSeries    HeightSeries
    ___________    __________    ____________

    10-Jan-2004      02:00           1.171   
    10-Jan-2004      12:00           0.808   
    26-Jan-2004      02:00           0.868   
    26-Jan-2004      12:00           0.319   
    11-Feb-2004      02:00           0.859   
    11-Feb-2004      12:00           0.354   
    19-Feb-2004      02:00           0.697   
    19-Feb-2004      12:00            1.56   
    19-Feb-2004      12:18          1.5045   
    27-Feb-2004      02:00           0.611   
    27-Feb-2004      12:00           0.307   
    14-Mar-2004      02:00           0.425   
    14-Mar-2004      12:00           0.204   
    22-Mar-2004      02:00           1.493   
    22-Mar-2004      12:00           0.958   
    07-Apr-2004      02:00           1.693   

[Ashfaq Ahmed]

Perfect!! Thank you so much!!

Answer 2

[Sulaymon Eshkabilov]

Here is one partial answer that finds the data pointsat specific times, i.e. 02:00, 03:00, 12:00, 13:00 and overlooks other time points such as s12:08, for example:

R =load('RESULT.mat').result;
IDX1 = find(ismember(R.HourSeries, '02:00'));
IDX2 = find(ismember(R.HourSeries, '03:00'));
IDX3 = find(ismember(R.HourSeries, '12:00'));
IDX4 = find(ismember(R.HourSeries, '13:00'));
Rs = R([IDX1,IDX2, IDX3, IDX4, IDX4],:);          % Selected
whos R Rs

  Name          Size              Bytes  Class    Attributes

  R         16282x3             2118115  table              
  Rs         2960x3              386255  table              

[Ashfaq Ahmed]

I liked this approach. It is meaningful. But Is there any way to get the interval time points? (i.e., 12:08)

Answer 3

[dpb]

Convert to datetime and use <isbetween>

result.HourSeries=duration(result.HourSeries,'InputFormat','hh:mm');
ix=isbetween(result.HourSeries,hours(2),hours(4))|isbetween(result.HourSeries,hours(12),hours(13));
result=result(ix,:);

Keeps only the selected entries; you lose the rest and would have to reload the .mat file if need any other data. Doing the conversion and reSAVEing first would probably be the smart thing; then save that step going forward.