In [ ]:

    

'''
pd.read_csv
pd.read_table
df.to_csv
'''


    

In [1]:

    

import numpy as np
import pandas as pd
from pandas import DataFrame,Series


    

In [7]:

    

csvfile = 'lecture25_in.csv'


    

In [8]:

    

df = pd.read_csv(csvfile)


    

In [9]:

    

df


    

    
Out[9]:






  

    

      

      
q
      
r
      
s
      
t
      
apple
    
  
  

    

      
0
      
2
      
3
      
4
      
5
      
pear
    
    

      
1
      
a
      
s
      
f
      
g
      
rabbit
    
    

      
2
      
5
      
8
      
3
      
7
      
dog
    
  

In [10]:

    

df = pd.read_csv(csvfile, header=None)


    

In [11]:

    

df


    

    
Out[11]:






  

    

      

      
0
      
1
      
2
      
3
      
4
    
  
  

    

      
0
      
q
      
r
      
s
      
t
      
apple
    
    

      
1
      
2
      
3
      
4
      
5
      
pear
    
    

      
2
      
a
      
s
      
f
      
g
      
rabbit
    
    

      
3
      
5
      
8
      
3
      
7
      
dog
    
  

In [12]:

    

df = pd.read_table(csvfile, sep=',', header=None)


    

In [13]:

    

df


    

    
Out[13]:






  

    

      

      
0
      
1
      
2
      
3
      
4
    
  
  

    

      
0
      
q
      
r
      
s
      
t
      
apple
    
    

      
1
      
2
      
3
      
4
      
5
      
pear
    
    

      
2
      
a
      
s
      
f
      
g
      
rabbit
    
    

      
3
      
5
      
8
      
3
      
7
      
dog
    
  

In [14]:

    

pd.read_csv(csvfile, header=None,nrows=2)


    

    
Out[14]:






  

    

      

      
0
      
1
      
2
      
3
      
4
    
  
  

    

      
0
      
q
      
r
      
s
      
t
      
apple
    
    

      
1
      
2
      
3
      
4
      
5
      
pear
    
  

In [15]:

    

df.to_csv('lecture25_out.csv')


    

In [16]:

    

# to show results inline
import sys


    

In [17]:

    

df.to_csv(sys.stdout)


    

    




,0,1,2,3,4
0,q,r,s,t,apple
1,2,3,4,5,pear
2,a,s,f,g,rabbit
3,5,8,3,7,dog

In [20]:

    

# saving with different delimiter
df.to_csv(sys.stdout,sep='_')


    

    




_0_1_2_3_4
0_q_r_s_t_apple
1_2_3_4_5_pear
2_a_s_f_g_rabbit
3_5_8_3_7_dog

In [21]:

    

# exporting specific columns
df.to_csv(sys.stdout,columns=[0,1,2])


    

    




,0,1,2
0,q,r,s
1,2,3,4
2,a,s,f
3,5,8,3

In [ ]: