pandas read_csv. How to ignore delimiter before line break

Question

I'm reading a file with numerical values.

data = pd.read_csv('data.dat', sep=' ', header=None)

In the text file, each row end with a space, So pandas wait for a value that is not there and add a "nan" at the end of each row. For example:

2.343 4.234

is read as: [2.343, 4.234, nan]

I can avoid it using , usecols = [0 1] but I would prefer a more general solution

Answer 1

You can use regular expressions in your sep argument.

Instead of specifying the separator to be one space, you can ask it to use as a separator any number of spaces until it finds the next value. You can do this by using the regular expression \s+:

data = pd.read_csv('data.dat', sep='\s+', header=None)