Python Day 5 - String functions

Python is dynamically typed programming language which means no need of entering datatype.Instead python will take datatype in default.
It is also called as duck typed programming language.

For reference: https://docs.python.org/3/library/string.html
https://peps.python.org/pep-0020/

String:

String(str) refers to words which should denoted in ' ' single quotes or " " double quotes.

Ex:

city = 'Madurai's Jigarthanda is very famous'
print(city)

For the above input,Output will be

SyntaxError: unterminated string literal

So even though string is defined in ' ' single quotes syntax error displays.The reason is string is incomplete Madurai's in this word we are using ' apostrophe but python consider this as a string and it is incomplete.

This error can be rectified by using three consecutive ''' ''' or """ """.

For ex:

city = '''Madurai's Jigarthanda is very famous'''
print(city)

city2= """Madurai's Jigarthanda is very famous"""
print(city2)

Address = """no. 7, East Street, 
            Mela masi veedhi,
            Madurai 625002"""

print(Address)

For the above inputs,output will be

Madurai's Jigarthanda is very famous
Madurai's Jigarthanda is very famous
no. 7, East Street, 
            Mela masi veedhi,
            Madurai 625002

Even for multiple lines string also you should use """ """ double quotes.

1.In python everything is an object.
2.Every object has its own memory space.
3.String is immutable.
For ex:

name = 'guru'
degree = 'B.com'
height = 170
sunday = False
print(id(name))
print(id(degree))
print(id(height))
print(id(sunday))

output will be

129009333595248
129009335659968
11759304
10654592

So print(id(#object name)) will be used for finding object's memory.

Index/subscript:(வரிசை)
Ex:
guru
0123

So indexing is used to access individual characters.In above example for g-0,u-1,r-2,u-3.
Indexing always starts from zero.

Ex:1

name = 'guru'

print(name[0])
print(name[1])
print(name[2])
print(name[3])

output:

g
u
r
u

Ex:2

name = 'guru'

print(name[0],end=' ')
print(name[1],end=' ')
print(name[2],end=' ')
print(name[3],end=' ')

output:

g u r u

For horizontal output use end=' '.If end is not used then output will be in vertical like Ex:1.

= is used to assign
== is used to compare.

String functions:
print(len(#object))-This is used to find length of a string.

ame = 'guru'

# first letter
print(name[0])
#last letter
print(name[3])
#first letter 'g'
if name[0] == 'g':
    print("yes starts with g")
#last letter 'u'
if name[3] == 'u':
    print("yes ends with u")
#all letters with single space in same line
print(name[0],end=' ')
print(name[1],end=' ')
print(name[2],end=' ')
print(name[3],end='\n')


#middle letter
length=len(name)#4
print(name[length//2])

In the above example // is used for division which is called as floor division.It will not take decimal points value.
Atlast \n is used for new line.
round()-It is used for round off decimal points.

output:

g
u
yes starts with g
yes ends with u
g u r u
r

Few string functions:

capitalize()-Converts the first character to upper case
casefold()-Converts string into lower case
endswith()-Returns true if the string ends with the specified value

Ex:

print(name.capitalize())

name = 'GuruPrasanna'
print(name.casefold())

print(name.endswith('Prasanna'))

Output:

Guru came to class today
guruprasanna
True