knnInterface: An Interface for class Package's knn Function

In ClassifyR: A framework for cross-validated classification problems, with applications to differential variability and differential distribution testing

Description

More details of k Nearest Neighbours are available in the documentation of knn.

Usage

  ## S4 method for signature 'matrix'
kNNinterface(measurements, classes, test, ...)
  ## S4 method for signature 'DataFrame'
kNNinterface(measurements, classes, test, ..., verbose = 3)
  ## S4 method for signature 'MultiAssayExperiment'
kNNinterface(measurements, test, targets = names(measurements), ...)

Arguments

measurements	Either a matrix, DataFrame or MultiAssayExperiment containing the training data. For a matrix, the rows are features, and the columns are samples. If of type DataFrame, the data set is subset to only those features of type integer.
classes	Either a vector of class labels of class factor of the same length as the number of samples in measurements or if the measurements are of class DataFrame a character vector of length 1 containing the column name in measurement is also permitted. Not used if measurements is a MultiAssayExperiment object.
test	An object of the same class as measurements with no samples in common with measurements and the same number of features as it.
targets	If measurements is a MultiAssayExperiment, the names of the data tables to be used. "clinical" is also a valid value and specifies that integer variables from the clinical data table will be used.
...	Variables not used by the matrix nor the MultiAssayExperiment method which are passed into and used by the DataFrame method or parameters that knn can accept.
verbose	Default: 3. A number between 0 and 3 for the amount of progress messages to give. This function only prints progress messages if the value is 3.

Details

Data tables which consist entirely of non-numeric data cannot be analysed. If measurements is an object of class MultiAssayExperiment, the factor of sample classes must be stored in the DataFrame accessible by the colData function with column name "class".

Value

A factor vector, the same as is returned by knn.

Author(s)

Dario Strbenac

Examples

  if(require(class))
  {
    classes <- factor(rep(c("Healthy", "Disease"), each = 5),
                      levels = c("Healthy", "Disease"))
    measurements <- matrix(c(rnorm(50, 10), rnorm(50, 5)), ncol = 10)
    colnames(measurements) <- paste("Sample", 1:10)
    rownames(measurements) <- paste("mRNA", 1:10)
  }
  
  kNNinterface(measurements[, 1:9], classes[1:9], measurements[, 10, drop = FALSE])

ClassifyR documentation built on Nov. 8, 2020, 6:53 p.m.