MATLAB Programming Fundamentals - MathWorks

Select Timetable Data by Row Time and Variable Type

A timetable is a type of table that associates a time with each row. You can subscript into

a timetable to select subsets of its data in a number of different ways. To select timetable

rows with row times that fall within a given time range, specify the time range using the

timerange function. Since a timetable is a table, you can index on rows and variables

using either smooth parentheses or curly braces. You can index on specific row times, or

select rows with row times that match specified times within a tolerance you set using the

withtol function. You can also subscript into a table or timetable to select all the

variables that match a type you specify with the vartype function. Finally, extract data

from a timetable into a matrix using the Variables property.

Create Timetable from File

Create a timetable from the sample file outages.csv, containing data representing

electric utility outages in the United States. Read the table from the file with the

readtable function. Convert T.Cause and T.Region into categorical arrays. Then

convert the table to a timetable using the table2timetable function. Display the first

five rows of the timetable. TT is a timetable containing outage data from February 2002 to

January 2014.

T = readtable('outages.csv');

T.Cause = categorical(T.Cause);

T.Region = categorical(T.Region);

TT = table2timetable(T);

TT(1:5,:)

ans=5×6 timetable

OutageTime Region Loss Customers RestorationTime Cause

________________ _________ ______ __________ ________________ _______________

2002-02-01 12:18 SouthWest 458.98 1.8202e+06 2002-02-07 16:50 winter storm

2003-01-23 00:49 SouthEast 530.14 2.1204e+05 NaT winter storm

2003-02-07 21:15 SouthEast 289.4 1.4294e+05 2003-02-17 08:14 winter storm

2004-04-06 05:44 West 434.81 3.4037e+05 2004-04-06 06:10 equipment fault

2002-03-16 06:18 MidWest 186.44 2.1275e+05 2002-03-18 23:23 severe storm

Summarize Timetable and Access Row Times

Display a summary of TT. It is a timetable that contains 1468 rows and five variables.

summary(TT)

10 Timetables