writetimetable

Write timetable to file.

📝Syntax

writetimetable(TT)
writetimetable(TT, filename)
writetimetable(..., Name, Value)

📥Input Arguments

Parameter	Description
TT	a timetable.
filename	a string specifying the destination filename.
Name, Value	optional write settings such as Delimiter, WriteVariableNames, WriteMode, QuoteStrings, and FileType.

📄Description

writetimetable writes a timetable to a delimited text file.

Row times are written as the first output column. Data variables are written after the row-time column and retain their variable names.

The supported text-file options match the practical surface of writetable, including Delimiter, WriteVariableNames, WriteMode, and QuoteStrings.

Datetime and duration row times are converted to stable text before writing. The resulting delimited text file can be read back with readtimetable.

JSON files (.json extension or 'FileType', 'json'): the timetable is written as a JSON array with one object per row. The row times are the first value of each object, keyed by the first dimension name. PrettyPrint and PreserveInfAndNaN behave as in writetable.

💡Examples

Write a timetable and read it back.

Time = datetime(2026, 1, 1) + hours(0:2)';
Temperature = [20.1; 21.3; 22.0];
Pressure = [1012; 1011; 1013];
TT1 = timetable(Time, Temperature, Pressure, ...
  'VariableNames', {'Temperature', 'Pressure'});
filename = [tempdir(), 'writetimetable_roundtrip.csv'];
writetimetable(TT1, filename);
TT2 = readtimetable(filename)

Use a semicolon delimiter.

Time = datetime(2026, 1, 1) + days(0:2)';
Temperature = [20.1; 21.3; 22.0];
TT = timetable(Time, Temperature);
filename = [tempdir(), 'writetimetable_semicolon.csv'];
writetimetable(TT, filename, 'Delimiter', ';');
fileread(filename)

Write duration row times.

Time = seconds([0; 5; 10]);
Signal = [3.2; 4.1; 3.8];
TT = timetable(Time, Signal);
filename = [tempdir(), 'writetimetable_duration.csv'];
writetimetable(TT, filename);
fileread(filename)

Append rows to an existing text file.

Time1 = datetime(2026, 1, 1) + hours(0:1)';
Value1 = [10; 11];
TT1 = timetable(Time1, Value1, 'VariableNames', {'Value'});
Time2 = datetime(2026, 1, 1) + hours(2:3)';
Value2 = [12; 13];
TT2 = timetable(Time2, Value2, 'VariableNames', {'Value'});
filename = [tempdir(), 'writetimetable_append.csv'];
writetimetable(TT1, filename);
writetimetable(TT2, filename, 'WriteMode', 'append', 'WriteVariableNames', false);
readtimetable(filename)

Write a timetable to a JSON file:

TT = timetable(datetime(2024, 1, 1) + days(0:2)', [12.5; 13; 11.75], 'VariableNames', {'Temperature'}); f = [tempdir, 'timetable_json.json']; writetimetable(TT, f, 'PrettyPrint', false); fileread(f) TT2 = readtimetable(f)

🔗See Also

readtimetable writetable timetable

🕔Version History

Version	Description
2.0.0	initial version
2.0.0	JSON files: FileType json, PrettyPrint and PreserveInfAndNaN.

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