Python#05

 File Operations in Python

How to open a file, read, print, write, append the contents.?  All shown with the following example code and output

 # Simple Excel file read

import pandas as pd

csv_file = pd.read_csv('csv.csv')

print(csv_file)


# # printed the following
#  h1  h2  h3  h4
# 0   1   2   3   4
# 1   5   6   7   8
# 2   9  10  11  12
# 3  13  14  15  16
# ##################
#Excel file sheet1 reading specific

excel_file = pd.read_excel('sample.xlsx', sheet_name='Sheet1')

print(excel_file)

# Print out
# Unnamed: 0  slno  name  age  sal
# 0           1     1     1    1    1
# 1           2     2     2    2    2
# 2           3     3     3    3    3
# 3           4     4     4    4    4
# read multiple sheets

df_sheet_multi = pd.read_excel('sample.xlsx', sheet_name=['Sheet1', 'Sheet2'])

print(df_sheet_multi)

#Printout
# {'Sheet1':    Unnamed: 0  slno  name  age  sal
# 0           1     1     1    1    1
# 1           2     2     2    2    2
# 2           3     3     3    3    3
# 3           4     4     4    4    4, 'Sheet2':    Unnamed: 0  slno  name  age  sal
# 0           1    11    11   11   11
# 1           2    22    33   44   55
# 2           3    66    66   66   66
# 3           4    77    77   77   77}

print(25*'-','Sheet1')

print(df_sheet_multi['Sheet1'])


# ------------------------- Sheet1
#    Unnamed: 0  slno  name  age  sal
# 0           1     1     1    1    1
# 1           2     2     2    2    2
# 2           3     3     3    3    3
# 3           4     4     4    4    4

print(25*'-','Sheet2')

print(df_sheet_multi['Sheet2'])


# ------------------------- Sheet2
#    Unnamed: 0  slno  name  age  sal
# 0           1    11    11   11   11
# 1           2    22    33   44   55
# 2           3    66    66   66   66
# 3           4    77    77   77   77

# To Create and write contents

f = open("demo.txt", "w")

f.write("I have written the contents!")

f.close()



#open and read the file after the appending:
f = open("demo.txt", "r")

print(f.read())

#prints  => I have written the contents!
f.close()


f = open("demo.txt", "a")

f.write("Now I have written the contents more again !")

f.close()

#In demo.txt => I have written the contents!Now I have written the contents more again !

import os.path

file_exists = os.path.exists('readme.txt')

print(file_exists)

#False

import os.path

file_exists = os.path.exists('demo.txt')

print(file_exists)

#True

f = open("demo1.txt", "w")

f.write("I have written the contents!")

f.close()


f = open("demo2.txt", "w")

f.write(str(list(csv_file)))


f = open("demo2.txt","r")

print(f.read())

#f.close()

print(f.read())

#Print ['h1', 'h2', 'h3', 'h4']

Hope The above simple code snippets and printouts shown as comments is clear and understandable. Happy Open and Distance Learning!