MATLAB Programming Fundamentals - MathWorks

Resample and Aggregate Data in Timetable

This example shows how to resample and aggregate data in a timetable. A timetable is a

type of table that associates a time with each row. A timetable can store column-oriented

data variables that have different data types and sizes, provided that each variable has

the same number of rows. With the retime function, you can resample timetable data, or

aggregate timetable data into time bins you specify.

Import Timetable

Load a timetable containing weather measurements taken from November 15, 2015, to

November 19, 2015. The timetable contains humidity, temperature, and pressure readings

taken over this time period.

load outdoors

outdoors(1:5,:)

ans=5×4 timetable

Time Humidity TemperatureF PressureHg

___________________ ________ ____________ __________

2015-11-15 00:00:24 49 51.3 29.61

2015-11-15 01:30:24 48.9 51.5 29.61

2015-11-15 03:00:24 48.9 51.5 29.61

2015-11-15 04:30:24 48.8 51.5 29.61

2015-11-15 06:00:24 48.7 51.5 29.6

Determine if the timetable is regular. A regular timetable is one in which the differences

between all consecutive row times are the same. outdoors is not a regular timetable.

TF = isregular(outdoors)

TF = logical

0

Find the differences in the time steps. They vary between half a minute and an hour and a

half.

dt = unique(diff(outdoors.Time))

dt = 3x1 duration array

00:00:24

Resample and Aggregate Data in Timetable