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(c) both are true

The syntax for csv.reader( ) is 

where csv.reader(fileobject,delimiter,fmtparams) 

file object – passes the path and the mode of the file 

delimiter – an optional parameter containing the standard dilects like, | etc can be omitted 

fmtparams – optional parameter which help to override the default values of the dialects like skipinitialspace,quoting etc. Can be omitted

import csv

row= [‘3’ , ‘Meena’ , ‘Bangalore’]

with open(‘student.csv’ , ‘r’) as readFile:

reader= csv.reader(readFile)

lines =list(reader) # list( ) – to store each row of data as a list

lines[3] =row

with open(‘student.csv’ , ‘w’) as writeFile:

# returns the writer object which converts the user data with delimiter

writer= csv.writer(writeFile)

#writerows( )method writes multiple rows to a csv file 

writer, writerows(lines)

readFile.close( )

writeFile.close( )

When we Open the student.csv file with text editor, then it will show:

Append mode write the value of row after the last line of the “student.csv file:”

The ‘w’ write mode creates a new file. If the file is already existing ‘w’ mode over writs it. Where as ‘a’ append mode add the data at the end of the file if the file already exists otherwise creates a new one.

A CSV file is a human readable text file where each line has a number of fields , separated by commas or some other delimiter. A CSV file is also known as a Flat File. Files in the CSV format can be imported to and exported from programs that store data in tables, such as Microsoft Excel or OpenOfficeCalc.

To open the file updating data, click +

(b) truncates the file

x opens a file for exclusive creation.

Python has a garbage collector to clean up unreferenced objects.

Create A CSV File Using Microsoft Excel:

To create a CSV file using Microsoft Excel, launch Excel and then open the file you want to save in CSV format.

For example, below is the data contained in our sample Excel worksheet:

Item Name, Cost-Rs, Quantity, Profit

Keyboard,480, 12,1152 ,

Monitor, 5200, 10, 10400

Mouse,200,50,2000

Total Profit = 13552

(a) the first two fields of the row are empty

sort( ) command arranges a list value in ascending order.

(d) Exam, Quarterly, Halfearly

(b) mumbai,andheri

(c) Modification

Dist( ) is used to remove the ordered Diet.

(a) orderedDist

1. sort(reverse)

2. itemgetter

List literals are written using [ ]

(d) DictReader( )

closing a file will free up the resources that were tied with the file and is done by close method.

append is used to add the elements in the list.

csv.register-dialects

writerow( ) method writes a row of data into the specified file.

(b) itemgetter(1)

(b) comma separated values

Answer is (d) #

Asterisk is not allowed to read data from cav files.

Answer is (c) dict( )

The number of parameters in csv.writer( ) 3

(a) (I),(II) – True (III) – False

(b) Quote-all

Answer is (c) doubled

(c) No such writerows( ) function in csv

(a) (I) is true, (II) is False

(a) xls Civdsx

(c) both a and b

dictionary keys

There are 3 arguments in csv.reader( ) functions.

(a) file object

(d) double quotes

(a) csv consumes less memory and faster

csv file is used to store tabular data such as spreadsheet or database.

(c) Fields containing line breaks, double quotes and commas should be enclosed in single quotes.

The syntax for csv.writer( ) is csv. writerffileobject, delimiter,fmtparams) where

fileobject : passes the path and the mode of the file. 

delimiter : an optional parameter containing the standard dilects like , | etc can be omitted. 

fmtparams : optional parameter which help to override the default values of the dialects like skipinitialspace,quoting etc. can be omitted.

Reading CSV File Into A Dictionary: To read a CSV file into a dictionary can be done by using DictReader class of csv module which works similar to the reader( ) class but creates an object which maps data to a dictionary. The keys are given by the fieldnames as parameter. DictReader works by reading the first line of the CSV and using each comma separated value in this line as a dictionary key.

The columns in each subsequent row then behave like dictionary values and can be accessed with the appropriate key (i.e. fieldname). The main difference between the csv.reader( ) and DictReader( ) is in simple terms csv. reader and csv.writer work with list/tuple, while csv.DictReader and csv.DictWriter work ‘ with dictionary. csv.DictReader and csv.DictWriter take additional argument fieldnames that are used as dictionary keys.

If the fields of data in csv file has commas, then it should be given with "

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 = openf’sample.txt”) bopen file in current directory andf is file object

>>> f = open(‘c:\ \pyprg\ \chl3sample5.csv’) #specifyingfull path

You can specify the mode while opening a file. In mode, you can specify whether you want to read ‘r’ , write ‘w’ or append ‘a’ to the file, you can also specify “text or binary” in which the file is to be opened.

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

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.

f = open(“test.txt”) # since no mode is specified the default mode it is used

#perform file operations

f.close( )

The above method is not entirely safe. If an exception occurs when you are performing some operation with the file, the code exits without closing the file. The best way to do this is using the “with” statement. This ensures that the file is closed when the block inside with is exited. You need not to explicitly call the close() method. It is done internally.

There are 2 ways to read a csv file.

import csv

row= [‘6’ , ‘Sajini’Madurai’]

with open(‘student.csv’ , ‘a’) as CF: # append mode to add data at the end

writer= csv.writer(CF)

writer.writerow(row) # writerow( ) method write a 

single row of data in file

CF.close( )

Output