从python第二行开始读取文件

Question

I use python and I don't know how to do.

I want to read lots of lines in files. But I have to read from second lines. All files have different lines, So I don't know how to do.

Code example is that it read from first line to 16th lines. But I have to read files from second lines to the end of lines. Thank you!:)

with open('filename') as fin:
  for line in islice(fin, 1, 16):
    print line

Answer 1

You should be able to call next and discard the first line:

with open('filename') as fin:
    next(fin) # cast into oblivion
    for line in fin:
        ... # do something

This is simple and easy because of the nature of fin , being a generator.

Answer 2

with open("filename", "rb") as fin:
    print(fin.readlines()[1:])

Answer 3

Looking at the documentation for islice

itertools.islice(iterable, stop)
itertools.islice(iterable, start, stop[, step])

Make an iterator that returns selected elements from the iterable. If start is non-zero, then elements from the iterable are skipped until start is reached. Afterward, elements are returned consecutively unless step is set higher than one which results in items being skipped. If stop is None, then iteration continues until the iterator is exhausted, if at all ; otherwise, it stops at the specified position. Unlike regular slicing, islice() does not support negative values for start, stop, or step. Can be used to extract related fields from data where the internal structure has been flattened (for example, a multi-line report may list a name field on every third line).

I think you can just tell it to start at the second line and iterate until the end. eg

with open('filename') as fin:
    for line in islice(fin, 2, None):  # <--- change 1 to 2 and 16 to None
        print line