I have a single csv file chr1.step1.csv, say it has five columns. I can read this as follows:
df=pd.read_csv('chr1.step1.csv',sep='\t',header=None)
df.head()
0 1 2 3 4 5
a1 b1 c1 d1 e1
a2 b2 c2 d2 e2
a3 b3 c3 d3 e3
How can I add 6th column as file name chr1.step1.csv, such as:
0 1 2 3 4 5 6
a1 b1 c1 d1 e1 chr1.step1.csv
a2 b2 c2 d2 e2 chr1.step1.csv
a3 b3 c3 d3 e3 chr1.step1.csv
Its only one file, not multiple files.
Assuming that 6th column name is Name File, and considering the file is in the path csv = '/home/User/Documents/file.csv' or csv = 'file.csv', one can do that using the os.path module.
import os.path
df['Name File'] = os.path.basename(csv)
One might also do, as @tdy suggests. Assign the name of the file to a variable
filename='chr1.step1.csv';
Then, assuming the df already exists (else one needs to read it, with something like df=pd.read_csv(filename,sep='\t',header=None)), assign the file name to the cells in a new column
df['Name File'] = filename
Extra: If one has a directory with lots of csv files
import pandas as pd
import glob
import os.path
# Create a list of all CSV files
files = glob.glob("*.csv")
# Create an empty list to append the df
filenames = []
for csv in files:
df = pd.read_csv(csv)
df['Name File'] = os.path.basename(csv)
filenames.append(df)
df[6] = "chr1.step1.csv"?filename='chr1.step1.csv'; df=pd.read_csv(filename,sep='\t',header=None); df[6]=filename? i think that's basically all you can do