How to read multiple text files into arrays?

Question

I have multiple text files, each containing several columns. I need to read each file into an array in python, called RDF. The point is that I used to read one file into one array as following:

RDF_1 = numpy.loadtxt("filename_1.txt", skiprows=205, usecols=(1,), unpak=True)

How to create a loop in python such that it reads more than one file into their corresponding arrays like this:

for i in range(100):
    RDF_i =  numpy.loadtxt("filename_"+str(i)+".txt", skiprows=205, usecols=(1,), unpak=True)

Answer 1

You can use dictionaries as a proper way:

files_mapping = dict()
for i in range(100):
    files_mapping[f'RDF_{i}'] = numpy.loadtxt(f"filename_{i}.txt", skiprows=205, usecols=(1,), unpak=True)

But if for some unknown reasons you really need to dynamically create variables then you can use exec :

for i in range(100):
    exac(f'RDF_{i} = numpy.loadtxt(f"filename_{i}.txt", skiprows=205, usecols=(1,), unpak=True)'

And another possible way is using locals :

for i in range(100):
    locals()[f'RDF_{i}'] = numpy.loadtxt(f"filename_{i}.txt", skiprows=205, usecols=(1,), unpak=True)

You need to avoid using two last options in real code because it's a direct way to spawning hard-to-find bugs.

Answer 2

I found a way to do it. I use two dimensional arrys after importing numpy library.

However, I had to zero the arrays before filling them out with data because python had already filled them out with random values.