CrestFactor (FPScript)

21.09.2021

Calculates the crest factor for a data set.

Syntax

CrestFactor(DataSet, [ Mode = PROCESS_COLUMNS ] [ , IntervalWidth ])

 

The syntax of the CrestFactor function consists of the following parts:

Part

Description

DataSet

The data set to be evaluated.

All data structures are allowed. All numeric data types are permitted.

For complex data types the absolute value is formed.

If the argument is a list, then the function is executed for each element of the list and the result is also a list.

Mode

Specifies how data matrices and signal series are to be processed and whether individual, moving or block crest factors are to be determined.

The argument Mode can have the following values:

Constant

Meaning

PROCESS_COLUMNS

Data matrices and signal series are processed column by column. The result is a data series or a signal with one crest factor per column.

PROCESS_ROWS

Data matrices and signal series are processed row by row. The result is a data series or a signal with one crest factor per row.

PROCESS_COMPLETE

Data matrices and signal series are processed as a whole. The result is a scalar value for the entire data set.

...plus an optional constant, which determines the calculation method:

Constant

Meaning

+ CALC_BLOCK

Block-by-block calculation. One value is calculated per interval.

+ CALC_MOVING

Moving calculation. For every value in the data set, a result is determined in the specified interval.

If the argument is a list, then the first element in the list is taken. If this is also a list, then the process is repeated.

If this argument is omitted, it will be set to the default value PROCESS_COLUMNS.

IntervalWidth

This argument is required for determining the moving and block crest factors. The interval width then specifies the number of values to be examined. The width should be an odd number. Otherwise, the interval is asymmetrical, and one more value is included in the calculation to the right of the center as opposed to the left.

Permitted data structures are scalar value. All integral data types are permitted.

The value must be greater or equal to 1.

If the argument is a list, then the first element in the list is taken. If this is also a list, then the process is repeated.

Remarks

The result always has the data type 64-bit floating point.

The crest factor of a sample is defined as:

For signals and signal series, the Y component is processed and the X or Z component is copied, if possible. When calculating moving and block crest factors, the data structure of the result corresponds to that of the argument. If, on the other hand, DataSet is a data series or a signal, the result is a scalar value with the crest factor searched for; otherwise, the result is a data series or a signal with one crest factor per column or row.

Available in

FlexPro Basic, Professional, Developer Suite

Examples

CrestFactor(Sin(Series(0, 2 * PI, 0.01)))

Results in 1.414979831240105. The crest factor of a sine wave is Sqrt(2).

CrestFactor({ Sin(Series(0, 2 * PI, 0.01)), Sawtooth(Series(0, 2 * PI, 0.01)) })

Results in { 1.414979831240105, 1.730172555653944 }. Calculates the crest factor for a sine or sawtooth wave.

See Also

Mean Function

Statistical Quantity Analysis Object

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