Source code for cerebras.modelzoo.common.model_utils.count_lines

# Copyright 2022 Cerebras Systems.
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# Licensed under the Apache License, Version 2.0 (the "License");
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from glob import glob
from itertools import repeat, takewhile


[docs]def count_lines(filename_pattern): """ Returns linecount in the given filename or sum over all of the filenames matching the pattern. Takes a filename pattern and globs the pattern to get all matching filenames. In order, this function reads all the files in raw format for a fixed buffer size till EOF is reached. It then counts the number of ``\n`` in each buffer and returns the sum. Using ``takewhile`` and ``repeat`` provides inbuilt speedup compared to writing custom while/for loop to handle EOF. `Note`: The size of the buffer is currently set to 1024*1024, but this is not optimized for all files. Some files can be read in faster by modifying the buffer size. This value is suboptimal to memory usage on a local dev instance. :param str filename_pattern: filename glob pattern (or filename) :returns: integer number of lines in the file """ line_count = 0 for filename in glob(filename_pattern): with open(filename, "rb") as f: bufgen = takewhile( lambda x: x, (f.raw.read(1024 * 1024) for _ in repeat(None)) ) line_count += sum(buf.count(b'\n') for buf in bufgen) # check if last line has "\n"; if not increment line count by 1 with open(filename, "r") as f: # seek to the end of the file f.seek(0, 2) # seek the last character of file f.seek(f.tell() - 1, 0) if f.read() != "\n": line_count += 1 return line_count