Create demo package

First some terminology: A package in python loosely means ‘a folder of .py files’. Each .py file is called a module, and can contain mutiple classes and functions. What we want to release is a package.

To set up a demo preate a new folder called MyPackage. This folder is where we are going to put all our source code, which is is what will eventually be built and uploaded to PyPi. The remaining directories and files we will be creating are purely for developers support, but won’t actually be distributed.

As some demo code, we are going to use a ‘sine_plotter’ function. Create a new python file inside MyPackage called sine_wave_utilities.py and copy the below code into it:

from matplotlib import pyplot as plt
import numpy as np


def generate_sine_data(Amplitude=1, Phase=0, Frequency=1, x_min=0, x_max=np.pi*2, n_samples=100):
    """
    generates sine data for the fiven input parameters

    :param Amplitude: amplitude of sine wave
    :type Amplitude: float
    :param Phase: phase of sine wave
    :type Phase: float
    :param Frequency: frequency of sine wave
    :type Frequency: float
    :param x_min: minimum x data
    :type x_min: float
    :param x_max: maximum x data
    :type x_max: float
    :param n_samples: number of samples in x
    :type n_samples: int
    :return: x, y: the x and y values of the generated sine plot
    """
    # create_data
    x = np.linspace(x_min, x_max, n_samples)
    y = (Amplitude * np.sin(x*Frequency))

    return x, y


def data_plotter(x, y, x_label='x', y_label='y', title='excellent graph', grid=True):  # pragma: no cover
    """
    just plots the data in x and y as a line plot

    :param x: x data for plotting;
    :type x: 1D list or array
    :param y: y data for plotting
    :type : 1D list or array
    :param x_label: x label
    :type x_label: st
    :param y_label:
    :type y_label:
    :param title:
    :type title:
    :param grid:
    :type grid:
    :return: None
    """

    # plot figure
    plt.figure()
    plt.plot(x, y)
    if grid:
        plt.grid()
    plt.xlabel(x_label)
    plt.ylabel(y_label)
    plt.title(title)
    plt.show()

2. Create a new file called __init__.py’ and copy the below code into it

"""
This library allows a user to plot a sine wave. It's fully sick.
"""
__version__ = '0.0.0'
import MyPackage.sine_wave_utilities

Always have an __init__.py file in the root of a package. It can be empty in many cases, but it should always be there.