Filling empty python dataframe using loops

Question

Lets say I want to create and fill an empty dataframe with values from a loop.

import pandas as pd
import numpy as np

years = [2013, 2014, 2015]
dn=pd.Data         


        

Answer 1

As far as I know you should avoid to add line by line to the dataframe due to speed issue

What I usually do is:

l1 = []
l2 = []

for i in range(n):
   compute value v1
   compute value v2
   l1.append(v1)
   l2.append(v2)

d = pd.DataFrame()
d['l1'] = l1
d['l2'] = l2