DataFrames Operation - Pandas

Pandas DataFrame operations

1. Creating DataFrame
2. Concatenate of DataFrames
3. Setting Conditions
4. Adding a New Column

Creating DataFrame

Program

import pandas as pd

#Creating DataFrame
cars = pd.DataFrame({'name':['benz','bmw','tata'], 'showroomprice':[12.5,24.6,10.6], 'onroadprice':[16.8,29.6,14.8]})
print("Cars Information:")
print(cars)

Output

Cars Information:
   name  showroomprice  onroadprice
0  benz           12.5         16.8
1   bmw           24.6         29.6
2  tata           10.6         14.8

Concatenate of DataFrames

Program

import pandas as pd

df1 = pd.DataFrame({'r1':[1,2,3],'r2':[4,5,6]})
df2 = pd.DataFrame({'r1':[7,8,9],'r2':[10,11,12]})
df = pd.concat([df1,df2])
print("Concatenated DataFrames")
print(df)

Output

Concatenated DataFrames
   r1  r2
0   1   4
1   2   5
2   3   6
0   7  10
1   8  11
2   9  12

Setting Conditions

Program

import pandas as pd

df = pd.DataFrame(range(1,21))
col1 = df.loc[df[0]%3==0]
print("DataDrame first column elements that are divisible by 3")
print(col1)

Output

DataDrame first column elements that are divisible by 3
     0
2    3
5    6
8    9
11  12
14  15
17  18

Adding a New Column

Program

import pandas as pd

#Creating DataFrame
cars = pd.DataFrame({'name':['benz','bmw','tata'], 'showroomprice':[12.5,24.6,10.6] })
print("Car Details:")
print(cars)
cars.insert(2,'onroadprice',[16.8,29.6,14.8],True)
print("After adding onroadprice column, Car Details:")
print(cars)

Output

Car Details:
   name  showroomprice
0  benz           12.5
1   bmw           24.6
2  tata           10.6
After adding onroadprice column, Car Details:
   name  showroomprice  onroadprice
0  benz           12.5         16.8
1   bmw           24.6         29.6
2  tata           10.6         14.8