an object the supports the read_lines
method, such as an laf object.
...
passed on to other methods.
rows
a numeric vector with the rows that should be
read from the file.
columns
an integer vector with the columns that
should be read in.
Details
Note that when scanning through the complete file
next_block is much faster. Also note that random file
access can be slow (and is always much slower than
sequential file access), especially for certain file types
such as comma separated. Reading is generally faster when
the lines that should be read are sorted.