thingSpeakRead

data = thingSpeakRead(channelID) reads the most recent data from all fields of the specified public channel on ThingSpeak.com and returns the data as a numeric type.

data = thingSpeakRead(channelID,Name,Value) uses additional options specified by one or more Name,Value pair arguments. To read nonnumeric data, you must specify the ‘OutputFormat’.

data = thingSpeakRead(___,'ReadKey','channel Read API key') uses the ThingSpeak™ Read API key to read from a private channel.

[data,timestamps] = thingSpeakRead(___) also returns timestamps from the specified channel on ThingSpeak.com and can include any of the input arguments in previous syntaxes.

[data,timestamps,channelInfo] = thingSpeakRead(___) also returns channel information.

Examples

Retrieve Three Points of Data from a Channel

Open Script

Retrieve the last five minutes of data from fields 1 and 4 of a public channel, and return the data in a timetable.

data = thingSpeakRead(12397,'Fields',[1,4],'NumPoints',3,'OutputFormat','TimeTable')

data =

  3×2 timetable

         Timestamps         WindDirectionNorth0Degrees    TemperatureF
    ____________________    __________________________    ____________

    15-Jan-2019 08:16:15               129                    26.1    
    15-Jan-2019 08:17:16               115                    26.1    
    15-Jan-2019 08:18:19               133                    26.2

Return Five Minutes of Data in a Timetable

Read the last five minutes of data from fields 1 and 4 of a public channel, and return the data in a table.

data = thingSpeakRead(12397,'Fields',[1,4],'Numminutes',5,'OutputFormat','TimeTable')

Retrieve Data Along with Timestamp

Retrieve the most recent result for all fields of a public channel, including the timestamps.

[data,timestamps] = thingSpeakRead(12397)

Return Five Minutes of Data Along with Timestamps and Channel Information

Retrieve the last five minutes of data from fields 1 and 4 of a public channel, including the timestamp and channel information.

[data,timestamps,channelInfo] = thingSpeakRead(12397,'Fields',[1,4],'NumMinutes',5)

Retrieve a Specific Date Range of Data with Timestamps and Channel Information

Retrieve the data from 11:59:01 on August 9, 2018 through 12:02:52 on August 10, 2018 for fields 1 and 4 of a public channel, including the timestamp and channel information.

[data,timestamps,channelInfo] = thingSpeakRead(12397,'Fields',[1 4],'DateRange',[datetime(2018,8,9,23,59,01),datetime(2018,8,10,0,02,52)])

Input Arguments

`channelID` — Channel identification number
numeric

The channel identification number, specified as a positive integer. For private channels, you must also specify the ‘ReadKey’ argument.

Data Types: double

Name-Value Pair Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Example: thingSpeakRead(12397,'Location',true);

`'DateRange'` — Range of data to return
datetime vector

Range of data to return, specified as a comma-separated pair consisting of 'DateRange' and an array of values that have [startdate,enddate] in MATLAB^® datetime values. ThingSpeak server limits the number of points returned to a maximum of 8000. Adjust your ranges or make multiple calls if you need more than 8000 points of data.

Note

You cannot use DateRange with NumDays or NumMinutes.

Example: thingSpeakRead(12397,'DateRange',[datetime('Aug 8, 2014'),datetime('Aug 12, 2014')]);

`'Fields'` — Channel fields
positive numeric scalar

Channel field IDs, specified as a comma-separated pair consisting of 'Fields' and numeric values of the channel field ID to retrieve data from.

Example: thingSpeakRead(12397,'Fields',[1,3,4]);

`'Location'` — Positional information of data
logical

Indicator to display positional information of data from the channel, specified as a comma-separated pair consisting of 'Location' and a logical value. Location information includes latitude, longitude, and altitude.

Example: thingSpeakRead(12397,'Location',true);

`'NumDays'` — Number of days of data
positive numeric scalar

Number of days of data to extract data from, specified as a comma-separated pair consisting of 'NumDays' and a numeric value. Number of days is measured in 24-hour periods. The ThingSpeak server limits the number of points returned to a maximum of 8000. Adjust your number of days, or make multiple calls if you need more than 8000 points of data.

Note

You cannot use NumDays with DateRange or NumMinutes.

Example: thingSpeakRead(12397,'NumDays',2);

`'NumMinutes'` — Number of minutes of data
positive numeric scalar

Number of minutes of data to extract data from, specified as a comma-separated pair consisting of 'NumMinutes' and a numeric value. Number of minutes of data to retrieve is measured from the time the command is issued. The ThingSpeak server limits the number of points returned to a maximum of 8000. Adjust your number of minutes, or make multiple calls if you need more than 8000 points of data.

Note

You cannot use NumMinutes with DateRange or NumDays.

Example: thingSpeakRead(12397,'NumMinutes',20);

Data Types: double

`'NumPoints'` — Number of data points
positive numeric scalar

Number of data points to extract, specified as a comma-separated pair consisting of 'NumPoints' and a numeric value. The number of points or rows of data is counted from the time the command is issued. The ThingSpeak server limits the number of points returned to a maximum of 8000.

Example: thingSpeakRead(12397,'NumPoints',200);

`'OutputFormat'` — Class of the output data
matrix (default) | table | timetable

Class of the output data, specified as a comma-separated pair consisting of 'OutputFormat' and a text value. Valid values are 'matrix', 'table', and 'timetable'. Use 'matrix' format for numeric data. You can use 'timetable' or 'table' for any nonnumeric data. The 'table' format outputs [data,channelInfo], where data contains the timestamps and the data from the fields of the channel. The 'timetable' format outputs [data,channelInfo], where data is a timetable and contains as many variables as the number of requested 'fields'.

Example: thingSpeakRead(12397,'OutputFormat','table');

Example: thingSpeakRead(12397,'OutputFormat','timetable');

`'ReadKey'` — Read API key of channel
character vector of API Key | string scalar of API Key

Read API key of the channel, specified as a comma-separated pair consisting of 'ReadKey' and a character vector representing a channel read API key. The Read API key allows you to read data from a private channel. You can find the Read API key for a channel on the API Keys tab of your ThingSpeak channel view. If you are reading data from a public channel, you do not need a Read API key. Save your channel Read API key in a variable for convenience.

Example: thingSpeakRead(12397,'ReadKey','F6CSCVKX42WFZN9Y');

Data Types: char

`'Timeout'` — Server connection timeout period
10 (default) | positive numeric scalar

Server connection timeout period, specified as a comma-separated pair consisting of 'Timeout' and a numeric value. The value is the number of seconds allowed for thingSpeakRead to connect to the server.

Example: thingSpeakRead(12397,'Timeout',15);

Output Arguments

`data` — Data from the channel
array (default) | table | timetable

Data from the channel, returned as an array, table, or timetable.

`timestamps` — Timestamp of each data element
array (default)

Timestamp of each data element, returned as an array of datetime values.

Data Types: datetime

`channelInfo` — Channel information
structure

Channel information, returned as a structure with fields in the order shown in the table..

Field	Description
`ChannelID`	Channel identification number
`Name`	Name of the channel
`Description`	Channel description
`Latitude`	Latitude for the channel as provided in the channel settings
`Longitude`	Longitude for the channel as provided in the channel settings
`Altitude`	Elevation for the channel as provided in the channel settings
`Created`	Datetime of channel creation date
`Updated`	Datetime when the channels settings were last changed
`Last EntryID`	Entry ID for the most recent channel update
`Field Descriptions`	List of field names
`Field IDs`	List of enabled fields
`URL`	URL for feed data

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