types.py

#font: http://cs231n.github.io/python-numpy-tutorial/
# Build in Functions: https://docs.python.org/3/library/functions.html

#Number
x = 3
print(type(x)) # Prints "<class 'int'>"
print(x)       # Prints "3"
print(x + 1)   # Addition; prints "4"
print(x - 1)   # Subtraction; prints "2"
print(x * 2)   # Multiplication; prints "6"
print(x ** 2)  # Exponentiation; prints "9"
x += 1
print(x)  # Prints "4"
x *= 2
print(x)  # Prints "8"
y = 2.5
print(type(y)) # Prints "<class 'float'>"
print(y, y + 1, y * 2, y ** 2) # Prints "2.5 3.5 5.0 6.25"


#Booleans
t = True
f = False
print(type(t)) # Prints "<class 'bool'>"
print(t and f) # Logical AND; prints "False"
print(t or f)  # Logical OR; prints "True"
print(not t)   # Logical NOT; prints "False"
print(t != f)  # Logical XOR; prints "True"


#String

hello = 'hello'    # String literals can use single quotes
world = "world"    # or double quotes; it does not matter.
print(hello)       # Prints "hello"
print(len(hello))  # String length; prints "5"
hw = hello + ' ' + world  # String concatenation
print(hw)  # prints "hello world"
hw007 = '%s %s %03d' % (hello, world, 7)  # printf-style String Formatting
print(hw007)  # prints "hello world"

country = 'Italy'
quantity = 4
print(country, "won", quantity, "world title", sep=" ") #Italy won 4 world title

day = 15
month = 3
year = 2020
print(day, month, year, sep="/") #15/3/2020

s = "hello"
print(s.capitalize())  # Capitalize a string; prints "Hello"
print(hw.title())      # Prints "Hello World"
print(s.upper())       # Convert a string to uppercase; prints "HELLO"
print(s.rjust(7))      # Right-justify a string, padding with spaces; prints "  hello"
print(s.center(7))     # Center a string, padding with spaces; prints " hello "
print(s.replace('l', '(ell)'))  # Replace all instances of one substring with another;
                                # prints "he(ell)(ell)o"
                                
print(s.endswith('llo'))   # Prints "True"
print(hw.find('ll'))       # Prints "2" where the substring starts
'll' in hw                 # Prints "True"
print('  world '.strip())  # Strip leading and trailing whitespace; prints "world"

# String interpolation
# https://docs.python.org/3/library/string.html#formatexamples
print("Tentativa {} de {}".format(1, 3))

print("Tentativa {1} de {0}".format(1, 3))

print("Cad$ {}".format(1.59))

print("Cad$ {:f}".format(1.59))

print("Cad$ {:.2f}".format(1.59))

print("Cad$ {:.2f}".format(1.5))

print("Cad$ {:7.2f}".format(1234.50))

print("Cad$ {:07.2f}".format(1.5))

print("Cad$ {:07d}".format(4))

print("Date {:02d}/{:02d}".format(9, 4))

#Containers
#Python includes several built-in container types: lists, dictionaries, sets, and tuples.

xs = [3, 1, 2]    # Create a list
print(xs, xs[2])  # Prints "[3, 1, 2] 2"
print(xs[-1])     # Negative indices count from the end of the list; prints "2"
xs[2] = 'foo'     # Lists can contain elements of different types
print(xs)         # Prints "[3, 1, 'foo']"
xs.append('bar')  # Add a new element to the end of the list
print(xs)         # Prints "[3, 1, 'foo', 'bar']"
x = xs.pop()      # Remove and return the last element of the list
print(x, xs)      # Prints "bar [3, 1, 'foo']"


nums = list(range(5))     # range is a built-in function that creates a list of integers
print(nums)               # Prints "[0, 1, 2, 3, 4]"
print(nums[2:4])          # Get a slice from index 2 to 4 (exclusive); prints "[2, 3]"
print(nums[2:])           # Get a slice from index 2 to the end; prints "[2, 3, 4]"
print(nums[:2])           # Get a slice from the start to index 2 (exclusive); prints "[0, 1]"
print(nums[:])            # Get a slice of the whole list; prints "[0, 1, 2, 3, 4]"
print(nums[:-1])          # Slice indices can be negative; prints "[0, 1, 2, 3]"
nums[2:4] = [8, 9]        # Assign a new sublist to a slice
print(nums)               # Prints "[0, 1, 8, 9, 4]"


# Loops
animals = ['cat', 'dog', 'monkey']
for animal in animals:
    print(animal)
# Prints "cat", "dog", "monkey", each on its own line.


# Enumerate function
animals = ['cat', 'dog', 'monkey']
for idx, animal in enumerate(animals):
    print('#%d: %s' % (idx + 1, animal))
# Prints "#1: cat", "#2: dog", "#3: monkey", each on its own line


# From Loops to List Comprehension:
nums = [0, 1, 2, 3, 4]
squares = []
for x in nums:
    squares.append(x ** 2)
print(squares)   # Prints [0, 1, 4, 9, 16]

###############


nums = [0, 1, 2, 3, 4]
squares = [x ** 2 for x in nums]
print(squares)   # Prints [0, 1, 4, 9, 16]


## List comprehensions can also contain conditions:
nums = [0, 1, 2, 3, 4]
even_squares = [x ** 2 for x in nums if x % 2 == 0]
print(even_squares)  # Prints "[0, 4, 16]"