Load Multiple Csv Files Into Dataframe: Columns Names Issue

I have multiple csv files with the same format (14 rows 4 columns). I tried to load all of them into a single dataFrame, and use file's name to rename the values of the first colum

Solution 1:

I think you need create list of DataFrames first, then concat with parameter keys for new values by range in MultiIndex, then modify column id and last remove MultiIndex by reset_index:

Also was added parameter names to read_csv for custom columns names.

Y = []
forxin S_Sub_list: 
    n = ['id', 'data', 'isEB', 'isEM']
    temp = pd.read_csv('sub' + str(x) +'_ICA_thre.csv', names = n)
    Y.append(temp)

#list comprehension alternative
#n = ['id', 'data', 'isEB', 'isEM']
#Y = [pd.read_csv('sub' + str(x) +'_ICA_thre.csv', names = n) forxin S_Sub_list]

df = pd.concat(Y, keys=range(1,len(S_Sub_list) + 1))

df['id'] = 'sub' + df.index.get_level_values(0).astype(str) +'_ICA_'+ df['id'].astype(str)
df = df.reset_index(drop=True)