DEV Community: johnnyhopkins28160@gmail.com

Calculating the Mean (Correction)

johnnyhopkins28160@gmail.com — Thu, 22 Apr 2021 15:44:52 +0000

Here is the program:

Programmer: Johnny L. Hopkins

Date: April 20, 2021

mean.py: Computing the aritmetic mean without using libraries

We will use matplotlib for basic visualizations based on the mean

import matplotlib.pyplot as plt

We need sample data to calculate the mean

We do this by declaring a new list

list_values = {80, 75, 93, 88, 99, 100, 80}

We will now build the equation for the mean by using

sum(), which takes the iterables in our list and sum over the

elements. To count the elements we will use len(). We can combine

the sum() and len() to build the equation for the mean. We declare a

new variable to store the value of the mean.

values_mean = sum(list_values) / len(list_values)

We now will print out the mean to the standard output:

print("The mean is: ", values_mean)

Finally, we will graph a histogram to see the distribution of values

To output the histogram, we have to specify the list as the values

to be graphed. If we don't specify a variable, an error is returned to

standard output

plt.hist(list_values, density = 1)
plt.show()

Here is the output:

Windows PowerShell
Copyright (C) Microsoft Corporation. All rights reserved.

Try the new cross-platform PowerShell https://aka.ms/pscore6

PS C:\Users\hopki> & python c:/Users/hopki/OneDrive/Documents/mean.py
The mean is: 89.16666666666667
PS C:\Users\hopki>

This comes directly from Visual Studio Code.

Calculating the Mean (Disclaimer)

johnnyhopkins28160@gmail.com — Wed, 21 Apr 2021 23:40:20 +0000

In posting today, I did not know the limitations on how to upload my screenshots of the program I explained. What I will do tomorrow is post the code within the post without screenshots from Visual Studio Code. However, it is still the coding environment for me and gives me everything I need without using a more feature-driven IDE like Visual Studio. So, I will post the raw code in my posts going forward. So, look for the corrected posts with some coding modifications tomorrow. I will eventually do some stuff with R as well. Both R and Python have democratized data science by allowing more people to use the language to analyze data.

Computing the Mean

johnnyhopkins28160@gmail.com — Wed, 21 Apr 2021 17:08:50 +0000

Calculating the Mean from Scratch using Python
In this post, I will explain a Python program that I wrote which calculates the mean without using the analytics libraries (NumPy, SciPy, etc.). The mean is a standard statistical expression used to calculate the average of a set of real numbers. There are two functions in Python used to calculate the mean from scratch. The first function is sum(), which calculates the sum of elements declared in a program. The program I wrote applies the function to add up a list of numbers and divides them by the len()function, which counts the number of elements declared in a list. When you divide sum()by len(), you get the equation for the mean, which you can declare in a program. The following screenshots show the code and a basic histogram of the values displayed in the program:

The screenshot shows the program where I declared a list of dummy values. Once I did this, I then built the equation for the mean, stored in the values_mean variable. Then, I printed the result to standard output. Finally, I generated a basic histogram using the matplotlib library and used hist() to output the histogram as we see here:

The graph is far from perfect, but it does give a simple visualization of values. In my next post, I will improve the program using the Ames data set, a standard set used in regression modeling. I will also improve upon the graphics to create a more descriptive distribution of values.

Visual Studio Code

johnnyhopkins28160@gmail.com — Wed, 21 Apr 2021 02:20:01 +0000

The cover photo you see on this posts is Visual Studio Code running on my HP Pavilion laptop I purchased recently. In my subsequent posts, I will post screenshots of my Python code running in Visual Studio Code. I love the IDE because there are extensions for most languages and platforms. I also appreciate the ability to run code in a terminal within the IDE. This is just a quick post on the software before I head for bed tonight. Tomorrow, I will post the mean.py program I worked on tonight and explain how it works.

New Python App

johnnyhopkins28160@gmail.com — Tue, 20 Apr 2021 18:12:05 +0000

This is my second post on dev.to. I plan to build a basic app calculating the mean from scratch without using any libraries. This evening or today, I will work on this program using either a data set or dummy data in a list. My goal is to write up this code today and post tonight or tomorrow. The program is very simple but powerful as I explain the methods used in the code. I plan to do a handful of simple apps each week and blog about them just to sharpen my skills and to keep up with my goal of blogging at least several times a week. I will extend this to calculating the variance and standard deviation from scratch as well. Some functions may be used to build the equation. The idea is to take basic statistical equations and work through them without using standard analytics libraries. Keep your eyes on the blog as I continue to write and put up code for you to follow, critique, and improve upon.

Hello

johnnyhopkins28160@gmail.com — Mon, 19 Apr 2021 00:22:08 +0000

This is my first post on dev.to. I hold two Bachelor degrees in Biology and Computer Science from UNC Greensboro and UNC Charlotte respectively. I hold two Associate of Applied Science degrees plus certificates in Java, Python, C++, and Front-End Web Development from Isothermal Community College. Finally, I hold a Master of Science in Management from Colorado Technical University. These colleges are in North Carolina, where I am from. I found out about this site from the Hanselman Minutes podcast. I have blogged for Topcoder in the past and seek to continue the process of writing as a way to strengthen my technical and programming skills.
With that being said, I will strive to do a post every day or every other day. I want to do my posts on Python and show you some demo programs and applications.