DSD_Memory

0th

Percentile

A Data Stream Interface for Data Stored in Memory

This class provides a data stream interface for data stored in memory as matrix-like objects (including data frames). All or a portion of the stored data can be replayed several times.

Usage
DSD_Memory(x, n, k=NA, loop=FALSE, class = NULL, description=NULL)
Arguments
x
A matrix-like object containing the data. If x is a DSD object then a data frame for n data points from this DSD is created.
n
Number of points used if x is a DSD object. If x is a matrix-like object then n is ignored.
k
Optional: The known number of clusters in the data
loop
Should the stream start over when it reaches the end?
class
Vector with the class/cluster label (only used if x is not a DSD object).
description
character string with a description.
Details

In addition to regular data.frames other matrix-like objects that provide subsetting with the bracket operator can be used. This includes ffdf (large data.frames stored on disk) from package ff and big.matrix from bigmemory.

Value

Returns a DSD_Memory object (subclass of DSD_R, DSD).

See Also

DSD, reset_stream

Aliases
  • DSD_Memory
Examples
# store 1000 points from a stream
stream <- DSD_Gaussians(k=3, d=2)
replayer <- DSD_Memory(stream, k=3, n=1000)
replayer
plot(replayer)  
  
# creating 2 clusterers of different algorithms
dsc1 <- DSC_DBSTREAM(r=0.1)
dsc2 <- DSC_DStream(gridsize=0.1, Cm=1.5)
  
# clustering the same data in 2 DSC objects
reset_stream(replayer) # resetting the replayer to the first position
update(dsc1, replayer, 500)
reset_stream(replayer)
update(dsc2, replayer, 500)
  
# plot the resulting clusterings
reset_stream(replayer) 
plot(dsc1, replayer, main="DBSTREAM")
reset_stream(replayer) 
plot(dsc2, replayer, main="D-Stream")   
  
### use a data.frame to create a stream (3rd col. contains the assignment)
df <- data.frame(x=runif(100), y=runif(100), 
  class=sample(1:3, 100, replace=TRUE))
head(df)  

stream <- DSD_Memory(df[,c("x", "y")], class=df[,"class"])  
stream
Documentation reproduced from package stream, version 1.2-3, License: GPL-3

Community examples

Looks like there are no examples yet.