Category: Python

Get The Learn to Code Course Bundle!
https://josephdelgadillo.com/product/learn-to-code-course-bundle/

Enroll in The Complete Python Course on Udemy!
https://www.udemy.com/python-complete/?couponCode=PYTHONWP

Welcome back everyone! We are on the last video of this tutorial series which means you now have a basic understanding of Python. You actually have enough knowledge right now to start building basic programs. We have covered some of the core concepts, as well as the language syntax, and we currently know how to create loops, if-elif-else statements, variables, etc. So, we are going to finish off the series with a project, specifically building a calculator in Python. Let’s go ahead an open up our ide.

import re

print("Our Magical Calculator")
print("Type 'quit to exit\n'")

previous = 0
run = True

def performMath():
global run
global previous
equation = ""
if previous == 0:
equation = input("Enter equation:")
else:
equation = input (str(previous))

if equation == 'quit':
print("Goodbye, human.")
run = false
else:
equation = re.sub('[a-zA-Z,.:()" "]', ' ', equation)

if previous == 0:
previous = eval(equation)
else:
previous = eval(str(previous) + equation)

while run:
performMath()

At the top of the script we are going to import the regex library, write a print statement welcoming our user, and inform our user how to exit the program. Next, we will define the previous and run variables. The previous variable will define the default value upon starting the program, and the run variable will determine whether the program is running or not.

Next, we will get into the meat of our calculator program. We will begin by defining the performMath function. Since the run and previous variables do not exist within our function, we will need to import them as global variables. Finally, we will define the equation variable.

Now that the performMath function is created, we will need to tell it what to do. The first if-else statement will request an input from the user. The second if-else statement will tell the program how to handle the user input. If the user types “quit”, the program will end and print “Goodbye, human.” Otherwise, the program will run a regex request on the input. Remember from the previous tutorial, we can use the regex library to identify and replace different sets of characters. We do not want the user inputting anything other than basic math. In the same block of code, we are going to run the eval function on the input from the user. If the user has already run a calculation, our program will take that result and add it to any additional calculations.

Lastly, we will create a while loop to run our performMath function. This is a very basic program and I would be interested to see any additions you make to it! Thank you to everyone who followed along with this tutorial series. I hope you found the information valuable!

Web – https://josephdelgadillo.com/
Subscribe – https://goo.gl/tkaGgy
Follow for Updates – https://steemit.com/@jo3potato

Get The Learn to Code Course Bundle!
https://josephdelgadillo.com/product/learn-to-code-course-bundle/

Enroll in The Complete Python Course on Udemy!
https://www.udemy.com/python-complete/?couponCode=PYTHONWP

In this tutorial we are going to cover the two loops types in Python. The first one is a for loop. A for loop will allow you to iterate over a list in Python. In other words, you can do something for each item in the list. So, let’s go ahead and create a list.

numbers = [1, 2, 3, 4, 5]

for item in numbers
print(item)

When we run this each number in our list will be printed out in the console. Let’s add names to our list instead of numbers.

names = ["Nick", "Someone", "Another Person"]

for item in names
print("This persons name is", item)

That is a for loop, and basically the second parameter is to access the list, and then the first parameter is what you want each item in the list to be called while inside it’s little block of code. Now we’re going to learn about a while loop.

run = True
current = 1

while run:
if current == 100:
run = False
else:
print(current)
current += 1

In this bit of code we are creating two variables, while, and then we write what we want to happen while the program is running. In this case, we are going to check to see if current = 100. If not, we are going to add 1 to the total, and we are starting from 1. Once the total hits 100 the program will stop running. We will be using loops quite a bit throughout this course, so make sure you’ve mastered this concept.

Web – https://josephdelgadillo.com/
Subscribe – https://goo.gl/tkaGgy
Follow for Updates – https://steemit.com/@jo3potato

Get The Learn to Code Course Bundle!
https://josephdelgadillo.com/product/learn-to-code-course-bundle/

Enroll in The Complete Python Course on Udemy!
https://www.udemy.com/python-complete/?couponCode=PYTHONWP

In this tutorial we are going to be learning about the conditional statements available to you in Python. So, we’re going to be learning about the if-else statement, and this is basically provides us a way to evaluate if something is true or false, and then perform something whether or not the condition is met. Let’s write an if-else statement.

check = True

if check == False:
print("It is false")
else:
print("It is actually equal to True")

This is going to print out “It is actually equal to True” in the console. First, Python is going to check if the variable is equal to false. Else, it’s going to continue through the script and print, or perform, whatever we tell it to do. This is great if we only have two conditions, but what if we want to use more than two? Between the if and else we can use an elif statement, and here we can supply an additional condition.

check = Hamburger

if check == False:
print(“It is false”)
elif check == “Hamburger”:
print(“Yummm, hamburgers”)
else:
print(“It is actually equal to True”)

When we run this script it’s going check to see if the first condition is true, if not it will check the next condition, if not it will print the else statement. So, that’s what an if-statement is, and these are necessary for the project we are about to begin working on.

Web – https://josephdelgadillo.com/
Subscribe – https://goo.gl/tkaGgy
Follow for Updates – https://steemit.com/@jo3potato

Get The Learn to Code Course Bundle!
https://josephdelgadillo.com/product/learn-to-code-course-bundle/

Enroll in The Complete Python Course on Udemy!
https://www.udemy.com/python-complete/?couponCode=PYTHONWP

Welcome back everyone. This is the final tutorial in the subsection for functions, and we’re going to be talking about return values from functions. Again, this may not be new to some of you as it is a fairly basic concept. So, in the past videos we have been using functions to print something out, but what if we want to return that value and do something else with it? Let’s go ahead and define a function.

def do_math(num1, num2):
return num1 + num2

do_math(5, 7)

Now when we run this bit of code, it’s not going to print anything in our Python console because we didn’t tell it to. Let’s add on to this.

def do_math(num1, num2):
return num1 + num2

math1 = do_math(5, 7)
math2 = do_math(11, 34)

print("First sum is", math1, "and the second sum is", math2)

When we run this we get the First sum is 12 and the second sum is 45. So, again, this a very simple example, but we will expand on this when we build our calculator.

Web – https://josephdelgadillo.com/
Subscribe – https://goo.gl/tkaGgy
Follow for Updates – https://steemit.com/@jo3potato

Get The Learn to Code Course Bundle!
https://josephdelgadillo.com/product/learn-to-code-course-bundle/

Enroll in The Complete Python Course on Udemy!
https://www.udemy.com/python-complete/?couponCode=PYTHONWP

In this video we are going to discuss passing an infinite number of arguments in to a function. So, let’s go ahead and write a function.

def print_people(*people):

So, here we have a function called print_people, and the asterisk tells this argument that it’s going to be an array of all the arguments that are passed in to the function. This may result in 1, 100, 1,000, etc. arguments, and we will see how this works in a moment. With an array we need some way to loop over it, and so we’re going to be using a for statement.

for person in people:
print("This person is", person)

Basically, the for loop allows us to iterate over the people list and pass the values into our function as arguments. Again, if you’re familiar with other programming languages this is not a new concept, it’s just a slightly different way of doing it. Let’s call the print_people function and pass it some names.

print_people("Nick", "Dan", "Jack", "King", "Smiley")

What we’re doing here is passing 5 arguments. Now if we knew we were always going to expect 5 arguments, we could accept each individual argument as it’s own variable. However, if we don’t know the total number of values, we are going to create an array stored in the variable called people. So, that’s how to include an infinite, or flexible, number of parameters. In the next tutorial we will cover return values.

Web – https://josephdelgadillo.com/
Subscribe – https://goo.gl/tkaGgy
Follow for Updates – https://steemit.com/@jo3potato

Get The Learn to Code Course Bundle!
https://josephdelgadillo.com/product/learn-to-code-course-bundle/

Enroll in The Complete Python Course on Udemy!
https://www.udemy.com/python-complete/?couponCode=PYTHONWP

Alright! So, let’s talk about keyword arguments. The first keyword, or boolean, that we are going to cover is None. Basically, this is the equivalent to null in other languages. So, let’s go ahead and write our previous function.

def print_something(name = "Someone", age = "Unknown"):
print("My name is", name, "and my age is", age)

print_something(None, 27)

There isn’t a way to pass in an argument that isn’t first one being used unless we use keyword arguments. We can also define the variable when we call the function.

def print_something(name = "Someone", age = "Unknown"):
print("My name is", name, "and my age is", age)

print_something(age = 27, name = "Nick")

By using keyword arguments, we can specify which value is supposed to go in a particular variable.

Web – https://josephdelgadillo.com/
Subscribe – https://goo.gl/tkaGgy
Follow for Updates – https://steemit.com/@jo3potato

Get The Learn to Code Course Bundle!
https://josephdelgadillo.com/product/learn-to-code-course-bundle/

Enroll in The Complete Python Course on Udemy!
https://www.udemy.com/python-complete/?couponCode=PYTHONWP

In this video we were going to discuss arguments a bit further, and we were going to move on to keyword arguments. Before we do that however, it is going to make more sense to cover default arguments first. So, let’s go ahead and write a function.

def print_something(name, age):
print("My name is ", name, + " and my age is " + age)

print_something("Nick", 27)

This won’t run. Remember, when we concatenate strings we must convert integers to strings as well. While we could use the str function to fix our code, it is much easier to separate the four pieces of data with commas.

def print_something(name, age):
print("My name is", name, "and my age is", age)

print_something("Nick", 27)

The results will be the same as if we converted the integer to a string and concatenated the four strings together. So, what happens if we only want to pass our function 1 of the 2 values? This is where we can use default arguments.

def print_something(name = "Someone", age = "Unknown"):
print("My name is", name, "and my age is", age)

print_something("Nick")

When we run this bit of code, Python will print out My name is Nick and my age is Unknown. As you can see, Python will default to the argument we provided it if no data is given.

Web – https://josephdelgadillo.com/
Subscribe – https://goo.gl/tkaGgy
Follow for Updates – https://steemit.com/@jo3potato