string_methods.py

# The capitalize() method returns a string where the first character is upper case, and the rest 
# are lower case.        

txt = "hello, and welcome to my world."
x = txt.capitalize()
print (x)

txt = "python is FUN!"
x = txt.capitalize()
print (x)

txt = "36 is my age."
x = txt.capitalize()
print (x)

#casefold() method is used for caseless matching. It is similar to lower() but more aggressive
#  because it is intended to remove all case distinctions in a string.  

txt = "Hello, And Welcome To My World!" 
x = txt.casefold()  
print(x)


#center() method will center align the string, using a specified character (space is default) as 
# the fill character.

txt = "banana"
x = txt.center(50)      
print(x)
txt = "banana"
x = txt.center(20, "*") 
print(x)        

#count() method returns the number of times a specified value occurs in a string.
txt = "I love apples, apple are my favorite fruit"
x = txt.count("apple")  
print(x)

x = txt.count("apple", 10, 24)
print(x)

# The encode() method encodes the string, using the specified encoding. If no encoding is specified,
#   UTF-8 will be used.
txt = "My name is Ståle"
x = txt.encode()
print(x)

print(txt.encode(encoding="ascii",errors="backslashreplace"))
print(txt.encode(encoding="ascii",errors="ignore"))
print(txt.encode(encoding="ascii",errors="namereplace"))
print(txt.encode(encoding="ascii",errors="replace"))
print(txt.encode(encoding="ascii",errors="xmlcharrefreplace"))


# The endswith() method returns True if the string ends with the specified value, otherwise False.
txt = "Hello, welcome to my world."
x = txt.endswith("y")
print(x)

x = txt.endswith("my world.", 5, 11)
print(x)

txt = "Hello, welcome to my castle."
x = txt.endswith(("world.", "castle."))
print(x)

# The expandtabs() method sets the tab size to the specified number of whitespaces.
txt = "H\te\tl\tl\to"
print(txt)
print(txt.expandtabs())
print(txt.expandtabs(2))
print(txt.expandtabs(4))
print(txt.expandtabs(10))

# The find() method finds the first occurrence of the specified value. The find() method returns -1 
# if the value is not found.
txt = "Hello, welcome to my world." 
x = txt.find("e")
print(x)    
x = txt.find("e", 5, 10)
print(x)
print(txt.find("q"))
#print(txt.index("q"))


# The format() method formats the specified value(s) and insert them inside the string's placeholder.
# The placeholder is defined using curly brackets: {}.  
txt = "For only {price:.2f} dollars!"
print(txt.format(price = 49))
txt = "My name is {fname}, I'm {age}".format(fname = "John", age = 36)
print(txt)  
txt = "My name is {0}, I'm {1}".format("John",36)
print(txt)      

# The format_map() method is similar to format(), but it takes a dictionary as an argument,
# where the keys are the placeholders in the string.        
my_dict = {'fname': 'Johnny', 'age': 36}
txt = "My name is {fname}, I'm {age}".format_map(my_dict)   
print(txt)  

# The index() method finds the first occurrence of the specified value. The index() method raises an
#  exception if the value is not found.
txt = "Hello, welcome to my world."
x = txt.index("d")
print(x)

x = txt.index("e", 5, 10)
print(x)    

print(txt.find("q"))
#print(txt.index("q"))

# The isalnum() method returns True if all characters in the string are alphanumeric (either 
# alphabets or numbers), and there is at least one character, otherwise False.

txt = "CompanyX%"
x = txt.isalnum()
print(x)


# The isalpha() method returns True if all characters in the string are in the alphabet, and there 
# is at least one character, otherwise False.

txt = "CompanyX12"
x = txt.isalpha()
print(x)

# The isdecimal() method returns True if all characters in the string are decimals, and there is at 
# least one character, otherwise False.

a = "\u0030" #unicode for 0
b = "\u0047" #unicode for G

print("is decimal:",a.isdecimal())
print("is decimal:",b.isdecimal())

# The isdigit() method returns True if all characters in the string are digits, and there is at 
# least one character, otherwise False
a = "\u0037" #unicode for 7
b = "\u0047" #unicode for G     
print("is digit:",a.isdigit())
print("is digit:",b.isdigit())  

# The isidentifier() method returns True if the string is a valid identifier, otherwise False.
# A string is considered a valid identifier if it only contains alphanumeric characters 
# (A-Z, a-z, 0-9) or underscores (_), and it does not start with a number. Python keywords cannot 
# be used as identifiers, even though they are valid identifiers.
txt = "123_Demo_123"
x = txt.isidentifier()
print("is identifier:",x)

txt = "DemoText"
x = txt.isidentifier()  
print("is identifier1:",x)

a = "MyFolder"
b = "Demo002"
c = "2bring"
d = "my demo"

print("is identifier2:",a.isidentifier())
print("is identifier3:",b.isidentifier())
print("is identifier4:",c.isidentifier())
print("is identifier5:",d.isidentifier())


# The islower() method returns True if all characters in the string are lower case, and there is at
# least one character, otherwise False.

txt = "hello worlD!"
x = txt.islower()
print("is lower:",x)

# The isnumeric() method returns True if all characters in the string are numeric, and there is
#  at least one character, otherwise False.

a = "\u0034" #unicode for 4
b = "\u0047" #unicode for G
print("is numeric:",a.isnumeric())
print("is numeric:",b.isnumeric())  

# The isprintable() method returns True if all characters in the string are printable, otherwise False.
txt = "Hello! Are you #1?"      
x = txt.isprintable()
print("is printable:",x)    

# The isspace() method returns True if all characters in the string are whitespaces, and there is at
#  least one character, otherwise False.
txt = " space  "
x = txt.isspace()
print("is space:",x)   

# The istitle() method returns True if the string follows the rules of a title, where the first
#  letter of each word is upper case, and the rest are lower case, otherwise False.
txt = "Hello, And Welcome To My World!"     
print("is title:",txt.istitle())


# The isupper() method returns True if all characters in the string are upper case, and there is at
#  least one character, otherwise False.    
txt = "THIS IS hOW!"
print("is upper:",txt.isupper())

# The join() method takes all items in an iterable and joins them into one string. A string must be
# specified as the separator.
myTuple = ("John", "Peter", "Vicky")
x = "#".join(myTuple)
print(x)

myDict = {"name": "John", "country": "Norway"}
mySeparator = "TEST"

x = mySeparator.join(myDict)

print(x)

# The ljust() method returns a left justified version of the string, using a specified character 
# (space is default) as the fill character.
txt = "banana"
x = txt.ljust(20)
print(x, "is my favorite fruit.")       

txt = "banana"
x = txt.ljust(20, "*")      
print(x, "is my favorite fruit.")

# The lower() method returns a string where all characters are lower case.
txt = "Hello my FRIENDS"
x = txt.lower()     
print(x)

# The lstrip() method returns a left trim version of the string. The lstrip() method removes any
# leading characters (space is the default leading character to remove).    
txt = "     banana     "
x = txt.lstrip()
print("of all fruits", x, "is my favorite")

txt = ",,,,,ssaaww.....banana"
x = txt.lstrip(",.asw")
print(x)

# The maketrans() method returns a translation table to be used in translations. The translate() method
#  takes a translation table and translates the string according to that table.
txt = "Hello Sam!"
mytable = txt.maketrans("S", "P")
print(txt.translate(mytable))

txt = "Good night Sam!"
x = "mSa"
y = "eJo"
z = "odnght"
mytable = str.maketrans(x, y, z)
print(txt.translate(mytable))
print(str.maketrans(x, y, z))


# The partition() method searches for a specified string, and splits the string into a tuple 
# containing three elements: the part before the specified string, the specified string itself, and
#  the part  after the string.
txt = "I could eat bananas all day"
x = txt.partition("bananas")        
print(x)

txt = "I could eat bananas all day"
x = txt.partition("apples")
print(x)


# The replace() method replaces a specified phrase with another specified phrase.
txt = "I like bananas"  
x = txt.replace("bananas", "apples")
print(x)    

txt = "one one was a race horse, two two was one too."
x = txt.replace("one", "three",2)
print(x)


# The rfind() method finds the last occurrence of the specified value. The rfind() method returns -1 if the value is not found.
txt = "Mi casa, su casa."   
x = txt.rfind("casa")
print(x)    
x = txt.rfind("casa", 0, 10)
print(x)    

# The rindex() method finds the last occurrence of the specified value. The rindex() method raises an exception if the value is not found.
txt = "Mi casa, su casa."
x = txt.rindex("casa")          
print(x)
x = txt.rindex("casa", 0, 10)
print(x)