g++ is a program that calls GCC (GNU C Compiler) and automatically links the required C++library files to the object code

CSV is a simple file format used to store tabular data, such as a spreadsheet or database. Since they're plain text, they're easier to import into a spreadsheet or another storage database, regardless of the specific software

'cd' command refers to change directory and absolute path refers to the couple path.
(Eg) "cd c:\program files\open office 4\program"

(i) SWIG - Simplified Wrapper Interface Generator
(ii) MinGW - Minimalist GNU for Windows

(i) The theoretical difference between the two is that scripting languages do not require the compilation step and are rather interpreted.
(ii) For example, normally, a C++ program needs to be compiled before running whereas, a scripting language like JavaScript or Python need not be compiled.
(iii) A scripting language requires an interpreter while a programming language requires a compiler. 

The row heading is get sorted, to avoid the first row should be skipped. This is can be done by using the command "next( )".

The default is reading in text mode. In this mode, while reading from the file the data would be in the format of strings.

A CSV file is a human readable text file where each line has a number of fields, separated by commas or some other delimiter.

(i) We can import the definitions inside a module to another module. We use the import keyword to do this.
(ii) Using the module name we can access the functions defined inside the module. The dot (.) operator is used to access the functions. The syntax for accessing the functions from the module is.
<module name>. <function name>
(iii) Example: >>> factorial.fact(5)

The commonly used interfaces are
(i) Python-C-API (API-Application Programming Interface for interfacing with C programs)
(ii) Ctypes (for interfacing with c programs)
(iii) SWIG (Simplified Wrapper Interface Generator- Both C and C++)
(iv) Cython (Cython is both a Python-like language for writing C-extensions)
(v) Boost. Python (a framework for interfacing Python and c++)
(vi) MinGW (Minimalist GNU for Windows)

(i) CSV file - data with default delimiter comma (,)
(ii) CSV file - data with Space at the beginning
(ill) CSV file - data with quotes
(iv) CSV file - data with quotes

To create a CSV file in Notepad,
(i) First open a new file using
File ⟶New or ctrl +N.
(ii) Then enter the data separating each value with a comma and each row with a new line.
(iii) For example consider the following details
Topic1, Topic2, Topic3
one, two, three
Example1, Example2, Example3
(iv) Save this content in a file with the extension.csv.

welcome → module name
      ●      →  operator name
display() → definition name

Program: To read a csv file with comma (,)
#importing csv
import csv
#opening the csv file which is in different location with read mode
with open('c:\\Pyprg\ \sample1.csv', 'r') as F:
#other way to open the file is
f=('C:\\pyprg\\sample1.csv', 'r')
reader = csv.reader(F))
#printing each line of the Data row by row.
print (row)
F. close( )
Output:
['SNO','NAME', 'CITY']
['12101', 'RAM', 'CHENNAI']
['12102', 'LAVANYA' "TIRUCHY']
['12103', 'LAKSHMAN', 'MADURAI']

(i) Python has a built-in function open() to open a file. This function returns a file object also called a handle, as it is used to read or modify the file accordingly.
For Example:
>>>f = open ("sample.txt") #open file in current directory # f is file object
>>> f =  open ('c:\\Pyprg\ch13 sample5.csv') # specifying full path
(ii) The default is reading in text mode. In this mode, while reading from the file the data would be in the format of strings.
(iii) On the other hand, binary mode returns bytes and this is the mode to be used when dealing with non-text files like image or exe files.

commands for wrapping C++ code:
if___name___ =='___main___':
main(sys.argv[ 1:])
_name_ (A Special variable) in Python:
(i) Since there is no main ( ) function in Python, when the command to run a Python program is given to the interpreter, the code that is at level 0 indentation is to be executed.
(ii) However, before doing that, interpreter will define a few special variables. __name___ is one such special variable which by default stores the name of the file. If the source file is executed as the main program, the interpreter sets the ___name___ variable to have a value as "___main___".
(iii) __name__ is a built-in variable which evaluates to the name of the current module. Thus it can be used to check whether the current script is being run on its own.
(iv) For example consider the following:
if ___name___ ==' ___main___':
main (sys.argv[1:])
(v) if the command line Python program itself is going to execute first, then _main_ contains the name of that Python program and the Python special variable _name_ also contain the Python program name.
(vi) If the condition is true it calls the main which is passed with C++ file as argument.

import csv
csv.register_dialect('myDialect', delimiter = '|', quoting=csv.QUOTE_ALL)
with open('c:\\pyprg\\ch13\\ grade.csv', 'w') as csvfile:
fieldnames = ['Name', 'Grade']
writer = csv.DictWriter(csvfile,
fieldnames=fieldnames. dialect ="myDialect")
writer.writeheader()
writer.writerows([{'Grade': 'B', 'Name': Anu'},
{'Grade': 'A', 'Name': 'Beena',},
{Grade': 'C', 'Name': 'Tarun'}])
print("writing completed")

Import csv
#opening the csv file which is in different location with read mode
f=open("c:\\pyprg\\ch13ample5.csv",'r')
#reading the File with the help of csv.reader( )
readFile=csv.reader(f)
#printing the selected column
for col in readFile:
print col[0],col[3]
f.close ( )
Sample5.csv File in Excel

Execution Steps:
//save above file as welcome.cpp
#Now select File -> New in Notepad and type the Python program
#save the file as fun.py
#Program that compiles and executes a .cpp file
#Python fun.py- iC: |pyprg| welcome - file.cpp
Program:
import sys, os, getopt
def main (argv):
cpp_file="
exe_file="
opts, args = getopt.getopt(argv, "i:", ['ifile='])
for o a in opts
if o in ("-i, "--ifile"):
cpp_file=a+ .'cpp'
exe_file = a+ 'exe'
run (cpp_file, exe_file)
def run (cpp_file, exe_file):
print("Compiling" + Cpp_file)
os.system ('g++' + cpp_file+'_o'+exe_file)
print("Running" + exe_file)
print("---------------")
print
Os.system(exe_file)
print
if_name_=='_main_':
main (sys.argv [1:])
Output:
welcome.

getopt() method returns value consisting of two elements. Each of these values are stored separately in two different list opts and args. opts contains list of splitted strings like made, path and args contains any string if at all not splitted because of wrong path or mode. args will be an empty array if there is no error in splitting strings by getopt().
Example:
The Python code which is going to execute the C++ file p4 in command line will have the getopt() method.
Syntax:
opts, args = getopt.getopt (argv, "i:", ['ifile ='])
where opts contains ('-i','c:\\pyprg\\p4')]]
-i:- option nothing but mode should be followed by
'c:\\pyprg\\p4' value nothing but the absolute path of C++ file,
Since the entire command-line commands are parsed and no leftover arguments, the second argunent args will be empty[].

(i) Python's Sys module:
This module provides access to some variables used by the interpreter and to functions that interact strongly with the interpreter.
Sys.argv:
(i) Sys.argv is the list of command-line arguments passed to the Python program.argv contains all the items that come along via the command-line input, it's basically an array holding the commandline arguments of the program.
(ii) To use sys.argv, we will first have to import sys. The first argument, sys.argv[O], is always the name of the program as it was invoked, and sys.argv[1] is the first argument you pass to the program (here it is the C++ file).
Example:
main (sys.argv [1]) Accepts the program file and input file as a list. argv [O] contains the Python program which is need not to be passed because bydefault_main_contains source code reference and argv [1] contains the name of the C++ file.
(ii) Python's OS module:
The OS module in Python provides a way of using operating system dependent functionality.
The functions that the OS module allows to interface with the windows operating system where Python is running on.
OS.system(): Execute the C++ compiling command in the shell.
Example:
os.system <'g++'+<variable - name 1> - '<mode>' <variable_name 2>
os.system: Function system() defined in os module. g++: General compiler to compile C++ program under
windows Operating system. Variable_name 1: Name of the C++ file without extension. cpp in string
format. Mode: To specify input or output mode. Here it is o prefixed
with hyphen. Variable_name 2: Name of the executable file without extension.exe in
string format. (iii) Python getopt module:
The getopt module of python helps to parse command-line options and arguments. This module provides two functions to enable command-line argument parsing.
getopt.getopt method:
This method parses command line options and parameter list.
Syntax:
<opts>, <args> = getopt.getopt(argv, options, [long_options])
argv - This is the argument list of values to be parsed.
options - This is string of option letters that the Python program recognize as, for input or for output with options 'i' or 'o' that followed by a colon(:).
Long- options - This parameter is passed with a list of strings. Argument of long options should be followed by an equal sign '='.

(i) Python uses Automatic Garbage Collection whereas C++ does not.
(ii) C++ is a statically typed language, while Python is a dynamically typed language.
(iii) Python runs through an interpreter, while C++ is pre-compiled.
(iv) Python code tends to be 5 to 10 times shorter than that written in C++.
(v) In Python, there is no need to declare types explicitly where as it should be done in C++.
(vi) In Python, a function may accept an argument of any type, and return multiple values without any kind of declaration beforehand. Whereas in C++ return statement can return only one value.

Rules to be followed to format data in a CSV file:
(i) Each record (row of data) is to be located on a separate line, delimited by a line break by pressing enter key.
For example:↲
xxx,yyy↲
↲denotes enter Key to be pressed
(ii) The last record in the file mayor may not have an ending line break.
For example:
ppp, qqq↲
yyy, xxx
(iii) There may be an optional header line appearing as the first line of the file with the same format as normal record lines. The header will contain names corresponding to the fields in the file and should contain the same number of fields as the records in the rest of the file.
For example:
field_name 1, field_name 2, field_name 3↲
aaa,bbb,ccc↲
zzz, yyy, xxx CRLF(Carriage Return and Line Feed)
(iv) Within the header and each record, there may be one or more fields, separated by commas. Spaces are considered part of a field and should not be ignored. The last field in the record must not be followed by a comma.
For example:
Red, Blue
(v) Each field mayor may not be enclosed in double quotes. If fields are not enclosed with double quotes, then double quotes may not appear inside the fields
For example:
"Red","Blue","Green"↲  
Black, White, Yellow 
(vi) Fields containing line breaks (CRLF), double quotes, and commas should be enclosed in double-quotes.
For example:
Red, ",", Blue CRLF 
Red, Blue, Green
(vii) If double-quotes are used to enclose fields, then a double-quote appearing inside a field must be preceded with another double quote.
For example:
"Red, " "Blue", "Green",
White

1. CSV file - data with default delimiter comma(,)
2. CSV file - data with space at the beginning.
3. CSV file - data with quotes
4. CSV file - data with custom Delimiters
1. CSV file - data with default delimiter comma(,):
The following program read a file called "Sample1.csv" with default delimiter comma (,) and print row by row.
Program:
#importing csv
import csv
#opening the csv file which is in different location with read mode
with opent('c.\\pyprg\\sample1.csv', 'r') as F:
#other way to open the file is f= ('C:\\pyprg\\ sample1.csv', 'r')
reader = csv.reader(F)
# printing each line of the Data row by row
print(row)
F.close()
Output:
['SNO', 'NAME', 'CITY']
['12101', 'RAM', 'CHENNAI']
['12102', 'LAVANYA', 'TIRUCHY']
['12103', 'LAKSHMAN', 'MADURAI']
2. CSV files - data with spaces at the beginning:
Consider the following file "Sample2.csv containing the following data when opened through notepad.

Topic 1	Topic 2	Topic 3
One,	two,	three,
Example 1,	Example 2,	Example 3,

Program:
import csv
csv.register_dialect ['my Dialect', delimiters=', 'Skipinitialspace= True).
F = open ('c:\\Pyprgl\sample2.csv', 'r')
reader = CSV.reader (F, dialect = 'myDialect')
for row in reader:
print (row)
F.close()
Output:
['Topic 1', 'Topic 2', 'Topic 3']
['One', 'two', 'three']
['Example 1', 'Example 2', 'Example 3']
We can see in "Sample 2.csv" there are spaces after the delimiter due to which the output is also displayed with spaces.
These whitespaces can be removed, by registering new dialects using csv. register _dialect( ) class of csv module. A dialect describes the format of the csv file that is to be read. In dialects the Parameter "skipinitialspace" is used for removing whitespaces after the delimiter.
3. CSV File - Data with Quotes:
We can read the csv files with quotes, by registering new dialects using csv. register_dialect( ) class of csv module.
SNO,                   Quotes
1,  "The Secret to getting ahead is getting started".
2, "Excellence is a continuous process and not an accident."
3,  "Work hard dream big never give up and believe Yourself"
4, "Failure is the opportunity to begin again more intelligently".
5, "The successful warrior is the average man, with laser-like focus."
Program:
import cSv
csv.register_ dialect ('MyDialect', delimiter =, 'quoting = csv.QUOTE_ALL, skipinitialspace = True)
f=open ('c:\\Pyprg\\ quotes.csv', 'r')
reader = csv.reader (f, dialect = 'myDialect')
for row in reader:
print (row)
Output:
['SNO, 'Quotes']
['1', 'The secret to getting ahead is getting started'.]
['2', 'Excellence is a continuous process and not an accident'.]
['3', 'Work hard dream big never give up and believe yourself'.]
['4', 'Failure is the opportunity to begin again more intelligently':]
['5', 'The successful warrior is the average man with laser- like focus':]
4. CSV files with custom Delimiters:
We can read csv file having custom the delimiter by registering a new dialect with the help of csv.register_dialect( ).
In the following file called "sample4.csv", each column is separated with |(Pipe Symbol)

Roll No	Name	City
12101	Arun	Chennai
12102	Meena	Kovai
12103	Ram	Nellai
103	Ayush	M
104	Abinandh	M

Program:
import csv
Csv. register_dialect('myDialect', delimiter= '|')
with open (c:\\pyprg\sample 4.csv', 'r') as f:
reader = csv.reader (f, dialect = "my dialect")
for row is reader:
print (row)
f.close()
Output:
['Roll no', 'Name', 'City]
['12101', 'Arun', 'Chennai']
['12102', 'Meena', 'Kovai']
['12103', 'Ram', 'Nellai']

Excel	CSV
Excel is a binary file that holds information about all the worksheets in a file, including both content and formatting	CSV format is a plain text format with a series of values separated by commas.
XLS files can only be read by applications that have been especially written to read their format, and can only be written in the same way.	CSV can be opened with any text editor in Windows like notepad, MS Excel, Open Office, etc.
Excel is a spreadsheet that saves files into its own proprietary format viz. xls or xlsx	CSV is a format for saving tabular information into a delimited text file with extension .csv
Excel consumes-more memory while importing data	Importing CSV files can be much faster, and it also consumes less memory