Working with table.

Hi all!

I have some data arranged in a table. I want to extract particular data values corresponding to a Date and do calculations with that value.

How can I do this?

For example:-

Let's say my data table is:

data =

date x y

____________________ ________ _________

03-Sep-2018 08:48:45 -1.3617 1.0391

29-Aug-2018 08:13:50 0.45503 -1.1176

24-Aug-2018 08:32:40 -0.84871 1.2607

19-Aug-2018 07:53:05 -0.33489 0.66014

14-Aug-2018 09:13:22 0.55278 -0.067866

So now how would I extract the value corresponding to "19-Aug-2018 07:53:05" in column "x" that is "-0.33489"?

Answer 1

[Steven Lord]

Do you need your data to be stored in a table or would a timetable be acceptable instead? Offhand I can't think of anything you can do with a table that you can't also do with a timetable, though the reverse is not true.

If you're not tied to storing your data in a table, convert it to a timetable using table2timetable. Once you've done that you can use a datetime as a row index, or you can use timerange or withtol if you're concerned that the dates and times in the RowTimes property of your timetable include fractional seconds that may not be shown in the display. See this documentation page for examples of these techniques.

[ADITYA GUPTA]

Actually I want to put the entire table data in .csv file. If this could be done using timetable than I'm fine with it. But I don't know how to do it.

Answer 2

[Peter Perkins]

>> t = table(datetime(2019,5,1:3)',[1;2;3],[4;5;6])
t =
  3×3 table
       Var1        Var2    Var3
    ___________    ____    ____
    01-May-2019     1       4  
    02-May-2019     2       5  
    03-May-2019     3       6  
>> tt = table2timetable(t)
tt =
  3×2 timetable
       Var1        Var2    Var3
    ___________    ____    ____
    01-May-2019     1       4  
    02-May-2019     2       5  
    03-May-2019     3       6  
>> tt('02-May-2019',:)
ans =
  1×2 timetable
       Var1        Var2    Var3
    ___________    ____    ____
    02-May-2019     2       5  
>> tt(timerange('02-May-2019','10-May-2019'),:)
ans =
  2×2 timetable
       Var1        Var2    Var3
    ___________    ____    ____
    02-May-2019     2       5  
    03-May-2019     3       6