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photobiology (version 0.13.2)

s_median: Median of a collection of spectra

Description

Method to compute the "parallel" median of values across members of a collection of spectra or of a spectral object containing multiple spectra in long form.

Usage

s_median(x, na.rm, ...)

# S3 method for default s_median(x, na.rm = FALSE, ...)

# S3 method for generic_spct s_median(x, na.rm = FALSE, ...)

# S3 method for source_mspct s_median(x, na.rm = FALSE, ...)

# S3 method for response_mspct s_median(x, na.rm = FALSE, ...)

# S3 method for filter_mspct s_median(x, na.rm = FALSE, ...)

# S3 method for reflector_mspct s_median(x, na.rm = FALSE, ...)

# S3 method for calibration_mspct s_median(x, na.rm = FALSE, ...)

# S3 method for cps_mspct s_median(x, na.rm = FALSE, ...)

# S3 method for raw_mspct s_median(x, na.rm = FALSE, ...)

Value

If x is a collection spectral of objects, such as a

"filter_mspct" object, the returned object belongs to the same class as the members of the collection, such as "filter_spct", containing the summary spectrum, with variables with names tagged for summaries other than mean or median.

Arguments

x

An R object.

na.rm

logical A value indicating whether NA values should be stripped before the computation proceeds.

...

Further arguments passed to or from other methods.

Deepest Curves

Parallel summaries differ fundamentally from the "deepest curves" obtained through functional data analysis (FDA) in that in functional data analysis one of the input curves is returned as the deepest one based on a decision criterion. In contrast the parallel summaries from package 'photobioloy' return one or more "fictional" curves different to any of those passed as inputs. This curve is constructed from independent summaries at each wavelength value.

Details

Method specializations compute the median at each wavelength across a group of spectra stored in an object of one of the classes defined in package 'photobiology'. Omission of NAs is done separately at each wavelength. Interpolation is not applied, so all spectra in x must share the same set of wavelengths. An error is triggered if this condition is nor fulfilled.

See Also

See median for the median() method used for the computations.

Examples

Run this code
s_median(sun_evening.mspct)

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