time2num

Convert duration or datetime array into numeric vector with the specified time unit

Since R2020a

Syntax

[x,origUnit] = time2num(T,targetUnit)

Description

time2num is a function used in code generated by Diagnostic Feature Designer.

[x,origUnit] = time2num(T,targetUnit) converts the time array T from its original data type and unit into a numeric vector x expressed in the unit of targetUnit. For instance, suppose that T is a datetime vector that contains timestamps for data measurements, and you want to convert T into a numeric vector x that expresses the time in units of hours. Use x = time2num(T,"hours").

If x is already a numeric vector, time2num sets x to T and ignores targetUnit.

Code that is generated by Diagnostic Feature Designer uses time2num when performing spectral processing and other computations.

Input Arguments

T — Time array

datetime array | duration array | numeric vector

Time array of sampling instants, expressed as a one-dimensional datetime array, a one-dimensional duration array, or a numeric vector.

targetUnit — Time unit

"seconds" | "minutes" | "hours" | "days" | "years" | " "

Time unit corresponding to the converted numeric vector, specified as a string. targetUnit can be one of the following:

• "seconds"

• "minutes"

• "hours"

• "days"

• "years"

• ""

If you omit targetUnit or set targetUnit to "", then time2num derives the original time unit from T.

• If T is a duration array, then time2num sets timeUnit to the unit of the duration array.

• If T is a datetime array, then time2num determines the best value for timeUnit based on sample time. For instance, if the timestamps in T are 100 seconds apart, time2num sets timeUnit to "minutes".

• If T is a numeric array, then time2num ignores targetUnit and sets x to T.

Example: tNumeric = time2num(Tacho.Time,"seconds")

Output Arguments

x — Sampling instants

numeric vector

Sampling instants, returned as a numeric vector. The starting point x(1) depends on the data type of T.

• If T is a datetime array, then x(1) is 0.

• If T is a duration array or a numeric vector, then x(1) is T(1), converted to the unit in targetUnit if targetUnit is specified.

• If T is a numeric vector, then x(1) is T(1).

origUnit — Original unit

string

Original unit of T, returned as a string.

Version History

Introduced in R2020a