runDensity: Find the clusters using flowDensity

In bgbrink/dropClust: Clustering algorithm for ddPCR data

Description

Use the local density function of the flowDensity package to find the cluster centres of the ddPCR reaction. Clusters are then labelled based on their rotated position and lastly the rain is assigned.

Usage

runDensity(file, sensitivity = 1, numOfMarkers, missingClusters = NULL,
  similarityParam = 0.95, distanceParam = 0.2)

Arguments

file	The input data. More specifically, a data frame with two dimensions, each dimension representing the intensity for one color channel.
sensitivity	A number between 0.1 and 2 determining sensitivity of the initial clustering, e.g. the number of clusters. A higher value means more clusters are being found. Standard is 1.
numOfMarkers	The number of primary clusters that are expected according the experiment set up.
missingClusters	A vector containing the number of primary clusters, which are missing in this dataset according to the template.
similarityParam	If the distance of a droplet between two or more clusters is very similar, it will not be counted for either. The standard it 0.95, i.e. at least 95% similarity. A sensible value lies between 0 and 1, where 0 means none of the 'rain' droplets will be counted and 1 means all droplets will be counted.
distanceParam	When assigning rain between two clusters, typically the bottom 20% are assigned to the lower cluster and the remaining 80% to the higher cluster. This parameter changes the ratio, i.e. a value of 0.1 would assign only 10% to the lower cluster.

Value

data	The original input data minus the removed events (for plotting)
counts	The droplet count for each cluster.
firstClusters	The position of the primary clusters.
partition	The cluster numbers as a CLUE partition (see clue package for more information).

Examples

# Run the flowDensity based approach
exampleFiles <- list.files(paste0(find.package('ddPCRclust'), '/extdata'), full.names = TRUE)
file <- read.csv(exampleFiles[3])
densResult <- runDensity(file = file, numOfMarkers = 4)

# Plot the results
library(ggplot2)
p <- ggplot(data = densResult$data, mapping = aes(x = Ch2.Amplitude, y = Ch1.Amplitude))
p <- p + geom_point(aes(color = factor(Cluster)), size = .5, na.rm = TRUE) +
     ggtitle('flowDensity example')+theme_bw() + theme(legend.position='none')
p

bgbrink/dropClust documentation built on Nov. 7, 2019, 12:18 p.m.