glycanr (version 0.3.0)

glyco.outliers: Discover outliers in glycan data

Description

Returns outliers within every glycan structure

Usage

glyco.outliers(data, group = NULL, outlier.function = NULL, alpha = 1.5)

Arguments

data

data frame in long format containing glycan measurements

group

a possible grouping parameter on which stratification of data should be conducted. It should be a name of one of the columns in dataframe data and of type factor.

outlier.function

a function that checks for outliers in a vector. Receives one parameter representing a vector and returns logical vector indicating outliers.

alpha

If outlier.function parameter is set to NULL outliers are calculated as those points that are greater than upper quartile + alpha * IQR (interquartile range) or lower than lower quartile - alpha * IQR (interquartile range). If parameter outlier.function is not NULL parameter alpha is not used.

Value

Returns a data.frame with outliers

Details

Input data frame should have at least the following three columns: - gid - representing a unique name of a sample - glycan - representing glycan names - value - representing measured values

Examples

data(mpiu)

glyco.outliers(mpiu)

# outliers per plate
glyco.outliers(mpiu, group="Plate")