How to Build a Python Calculator to Compute Sin and Cos Values

This guide walks through the process of building a python calculator to calculate sin and cos values.

Introduction

This guide walks through the process of building a python calculator to calculate sin and cos values. We will learn how to implement the code needed, such as arithmetic operations and taking user input.

Setup

Before we begin writing code, let's set up a few things that we need.

Python Installation

We will need Python 3 or later to be installed on our machine. To install Python, open any web browser, and search for the version of Python you need. Follow the instructions to download and install the program.

Setting Up the Environment

Once Python is installed, we will need to create a new environment. To do this, open the terminal and type in the following command:

python -m venv [folder name]

This command creates a virtual environment for us to work in. We can activate this environment by running source [folder name]/bin/activate.

Installing Python Packages

Now, let's install the needed Python packages. We will need Math, Numpy, and Matplotlib. To install these packages, type in the following command into the terminal:

pip3 install math, numpy, matplotlib

Writing the Code

Now that we have everything installed, we can start writing the code for our calculator.

Imports

Let's begin by importing the packages we need for our calculator.

import math
import numpy
import matplotlib.pyplot as plt

Taking User Input

Now, let's take the user input for the angle they want to calculate the sin and cos value for. To do this, we will use the input() function.

angle = float(input('Please enter the angle you would like to calculate for: '))

Compute Sin and Cos Values

Now, let's compute the sin and cos values. To do this, we will use the math.sin() and math.cos() functions. We will also need to convert the angle to radians using the math.radians() function.

angleInRadians = math.radians(angle)
sinVal = math.sin(angleInRadians)
cosVal = math.cos(angleInRadians)

Plotting the Results

We will use Matplotlib to create a plot of the sin and cos values.

xValues = numpy.arange(-2 * math.pi, 2 * math.pi, 0.1)
sinValues = [math.sin(x) for x in xValues]
cosValues = [math.cos(x) for x in xValues]

plt.plot(xValues, sinValues, label='sin(x)')
plt.plot(xValues, cosValues, label='cos(x)')

plt.axhline(y=sinVal, color='red', label='sin(' + str(angle) + ')')
plt.axhline(y=cosVal, color='blue', label='cos(' + str(angle) + ')')

plt.legend()

plt.show()

Conclusion

In this guide, we built a calculator to calculate sin and cos values for a given angle using Python. We walked through setting up our environment, taking user input, computing sin and cos values, and plotting the results.