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tdmsread

Read data from TDMS-file

Description

example

data = tdmsread(tdmsfile) retrieves data from the specified TDMS-file and returns a cell array of tables. Each element of the cell array is a table corresponding to a channel group.

data = tdmsread(tdmsfile,Name=Value) uses name-value pairs to filter the data reading and specify output format.

Examples

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Read data from a specified TDMS-file. You can determine which channels are read, and what format the result has.

Read all data from a TDMS-file into a table.

data = tdmsread("airlinesmall.tdms");

Read a subset of the variables in a TDMS-file into MATLAB as a timetable. Use the variable ArrTime in the TDMS-file as the time vector of the output timetable.

data = tdmsread("airlinesmall.tdms", ...
           ChannelGroupName = "Airline", ...
           ChannelNames = ["ArrTime" "FlightNum" "ArrDelay"], ...
           RowTimes = "ArrTime");

Read the channel data into a timetable with a specified start time and step duration.

data = tdmsread("airlinesmall.tdms", ...
           ChannelGroupName = "Airline", ...
           ChannelNames = ["ArrTime" "FlightNum" "ArrDelay"], ...
           TimeStep = seconds(0.01), StartTime = seconds(30));

Input Arguments

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TDMS file name, specified as a string.

For local files, use a full or relative path that contains a file name and extension. You also can specify a file on the MATLAB path.

For Internet files, specify the URL. For example, to read a remote file from the Amazon S3 cloud:

data = tdmsread("s3://bucketname/path_to_file/data.tdms");

Example: "airlinesmall.tdms"

Data Types: char | string

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example: ChannelGroupName="Torque",ChannelNames="Torque1"

Supported name-value pairs are:

Channel group containing the channels to read from, specified as a string or character vector.

Example: "Torque"

Data Types: string | char

Names of channels to read, specified as a string, string array, character vector, or cell array of character vectors. The channels must be in the channel group specified by ChannelGroupName.

Example: ["Torque1" "Torque2"]

Data Types: char | string | cell

Times associated with rows of the table, specified as a selected time channel name, a datetime vector, or a duration vector. Specifying this option causes the function to output a cell array of timetables. Each time element labels a row in the output timetable.

Example: duration(seconds([1:1000]/1000))

Data Types: datetime | duration | string

Start time of the output timetable, specified as a scalar datetime or duration indicating the time of the first data record in the timetable.

Example: StartTime=seconds(60)

Data Types: datetime | duration

Sample rate of the output timetable, specified as a positive scalar double indicating samples per second.

Example: SampleRate=1000

Data Types: double

Time step of the output timetable, specified as a scalar duration or calendarDuration indicating the time span between data records.

Example: TimeStep=seconds(0.01)

Data Types: duration | calendarDuration

Output Arguments

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Output data, returned as a cell array of tables or timetables with data records from the TDMS-file. Each element of the cell array is a table or timetable for a channel group. The cell array index corresponds to the channel group number.

Version History

Introduced in R2022a

See Also

Functions