Python Language Basics - 2

Slice string in python:

details= "Akshay Kumar Gupta--akshaygupta.me"

# details[:6] and details[0:6] will give same result

print(details[:6]) # OUTPUT: Akshay

# details[20:] and details[20:34] will give same result

print(details[20:]) # OUTPUT: akshaygupta.me

# -1 denotes the reverse order

print(details[11::-1]) #OUTPUT: ramuK yahskA

# Here -9 denotes the count from the end of the string

print(details[:-9:-1]) #OUTPUT: em.atpug

#Both syntax gives the same result for reversing the string

print(details[-1::-1]) #OUTPUT: em.atpugyahska--atpuG ramuK yahskA

print(details[::-1]) #OUTPUT: em.atpugyahska--atpuG ramuK yahskA

Format print in python:

print("hi, My name is {} and I am a {}. I like {}."

.format("Akshay", "Software Engineer", "python"))

• In the above print statement, "{}" refers to the placement of the values given in "format()" function.
• First value in the order "format()" function will replace the first "{}" in the given string and so on.

print("hi, I am studying {0} language. It is easy to understand. {0} is generally used in {1}."

.format("python", "data science"))

• In above example index number is defined inside the "{}" that refers to the position of the values in "format()" function.
• "{0}" refers to the "python" and used two times in the string.

print("I got {0:15}% in my exam that is approx {0:5.1f}%. {1:10} was tough but I passed."

.format(69.967789, "math test"))

• {0:15} refers to the {<position> : <spaces before the value in string>}
• {0:5.1f} refers to the {<position> : <spaces before the value in string>.<round off value in float>f}
• "1f" means value will be round off to one digit after the decimal.
• Out of theh above print statement will be:

hi, I am studying python language. It is easy to understand. python is generally used in data science.. I got 69.967789% in my exam that is approx 70.0%. math test was tough but I passed.

f-string in python:

marks = 69.967789

print(f"I got {marks}% in my exam that is approx {marks:5.1f}%.")

• Put letter "f" before writing the string.
• Use the {} and put the value in it.
• It follows the below formatting inside {}:

{<value>: <spaces before the value>.<round off to the given number for float values>f}

example: print(f"{69.967789:30.2f} is the my marks after round off two two digits")

> I got 69.97 marks after round off two two digits will give below output:

Sorting a list in Python:

# Sorting Numbers
numbers = [1, 4, 5, 3, 2]
# Immutable method for sorting
print(sorted(numbers))
# Mutable method for sorting
numbers.sort()
print(numbers)

# Sorting String
web_link = "AkshayGupta.Me"
# Immutable method for sorting
print(sorted(web_link))

#  Case-Insensitive Sorting
# Immutable
countries = ["India", "USA", "Egypt", "UK"]
print(sorted(countries, key=str.casefold))
# Mutable
countries.sort(key=str.casefold)
print(countries)

Slice and replace the elements in list:

countries = ["India", "USA", "Egypt", "UK"]
countries[2:] = ["Russia", "Indonesia"]
print(countries)  # ['India', 'USA', 'Russia', 'Indonesia']

Delete elements from list in python:

countries = ["India", "USA", "Egypt", "UK"]
# delete multiple countries
del countries[2:]  # ['India', 'USA']
# delete single country
del countries[1]  # ['India', 'Egypt', 'UK']