Replace column values in large Pandas dataframe
Use pd.read_csv("path_to_file", header=0).
If you also want to assign names to the columns you can pass a list in the names parameter of pd.read_csv.
I have a large input file of numerical data (22000) columns and at the moment when I use
df = pd.read_csv(path_to_file), it uses the first line of numbers as the column values. 
Is there any way to replace the column value with random variables or load the data in a way that the first line is not used as a column name?