Generates a two dimensional data stream containing events of two classes.
This function generates a two-dimensional data stream containing events of two classes. The data stream can be saved as separate files with images by specifying the argument folder.
gen_stream( n, folder = NULL, sd = 1, vis = FALSE, muAB = c(4, 3), sdAB = c(2, 3) )
n: The number of files to generate. Each file consists of a 350x250 data matrix.folder: If this is set to a local folder, the data matrices are saved in folder/data, the images are saved in folder/pics and the event details are saved in folder/summary. The event details are needed to obtain the class labels of events, when event extraction is done.sd: This specifies the seed.vis: If TRUE, the images are plotted.muAB: The starting event pixels of class A and B events are normally distributed with mean values specified by muAB. The default is c(4,3).sdAB: The starting standard deviations of class A and B events. Default set to c(2,3).A list with following components: - data: The data stream returned as a data frame.
details: A data frame containing the details of the events: their positions, class labels, etc.. . This is needed for identifying class labels of events during event extraction.
eventlabs: A matrix with 1 at event locations and 0 elsewhere.
There are events of two classes in the data matrices : A and B. Events of class A have only one shape while events of class B have three different shapes, including class A's shape. This was motivated from a real world example. The details of events of each class are given below.
| Feature | class A | class B |
| Starting cell/pixel values | N(4,2) | N(3,3) |
| Ending cell/pixel values | N(8,2) | N(5,3) |
| Maximum age of event - shape 1 | U(20,30) | U(20,30) |
| Maximum age of event - shape 2 | NA | U(100,150) |
| Maximum age of event - shape 3 | NA | U(100,150) |
| Maximum width of event - shape 1 | U(20,26) | U(20,26) |
| Maximum width of event - shape 2 | NA | U(30,38) |
| Maximum width of event - shape 3 | NA | U(50,58) |
out <- gen_stream(1, sd=15) zz <- as.matrix(out$data) image(1:nrow(zz), 1:ncol(zz),zz, xlab="Time", ylab="Location")
stream_from_files.