Fast Access to Large ASCII Files
Read records from a large file object into R
Column of a Large File Object
Create a connection to a comma separated value (CSV) file.
Create a connection to a fixed width file.
Create a connection to a file using a data model.
Large File object
Get and change the levels of the column in a Large File object
Get and set the names of the columns in a Large File object
Get the number of columns in a Large File object
Read the next block of data from a file.
Get the number of rows in a Large File object
Read in specified lines from a text file
Go to specified line in the file
Determine number of lines in a text file
Go to the beginning of the file
Select a column from a LaF object
Close the connection to the Large File
Get the current line in the file
Read and write data models for LaF
Automatically detect data models for CSV-files
Blockwise processing of file
Read in Blaise data models
Read lines from the file
Read in random lines from a text file
Print the Large File object to screen
Calculate simple statistics of column
Methods for fast access to large ASCII files. Currently the following file formats are supported: comma separated format (CSV) and fixed width format. It is assumed that the files are too large to fit into memory, although the package can also be used to efficiently access files that do fit into memory. Methods are provided to access and process files blockwise. Furthermore, an opened file can be accessed as one would an ordinary data.frame. The LaF vignette gives an overview of the functionality provided.