### Python Matplotlib for Beginners

**Prerequisites**

**Hardware : Local Machine**

**Software : Jupyter Notebook**

**Programming Language : Python **

**Definition:**

**Matplotlib is a cross-platform, data visualization and graphical plotting for Python.**

**Jupyter Notebook Introduction:**

**Jupyter** is a free, open-source, interactive web tool which known as a computational **notebook**, which anybody can **use** to combine software code to get the computational output, explanatory text in a single document.

**PLOT A LINE IN Matplotlib:**

You can run the following code in **Jupyter Notebook:**

Click this link to open Jupyter Notebook – https://jupyter.org/

**plt.plot() –**

A function which is used to plot the points between x and y.

**plt.show()**

Function which shows the plot.

What is Matplotlib?

**matplotlib.pyplot** is a collection of command style functions which makes matplotlib work like MATLAB

Each `pyplot`

function can make any changes to a figure. For example It can create a figure, It can also create a plotting area in the figure, A function which plots some lines in a plotting area

** What is Pyplot? **

**Pyplot package can be considered as plt.**

**SIMPLE PLOT:**

Let’s display a simple line plot by using the math module which uses mathematical functions.

Here is the program for the reference** Simple Plot**:

What is Numpy?

NumPy is a module for the Python programming language for large multi-dimensional arrays and matrices

**import numpy as np** – In simple terms making short “**numpy**” to “**np**” to make your code easier to read.

**import math** – . The math module uses mathematical functions

**np.arrange()** –

**NumPy arange()** Creation of an array using routines based on numerical ranges. It is also for

**Setting the coordinates**

**np.sin() – **

It is a mathematical function which helps user to calculate trignometric **sine**.

**plt.plot() –**

A function which is used to plot the points between x and y.

**MULTI PLOT:**

This allows to draw multiple graphs in a single plot.

A subplot () function is known as wrapper function which allows user to plot more than one graph in a single figure

Here is the program for the reference **Multi Plot:**

**plt.plot([1, 2, 3)]**

Plot a line, Implicitly creating a subplot

**What is a Subplot?**

Subplots can connect to main plots.

**plt.subplot(211)**

Creation of a subplot that represents the top plot of a grid with 2 rows and 1 column.

**plt.subplot(212, facecolor=’y’)**

As we can see it creates 2nd subplot with yellow background

**BAR PLOT:**

A bar graph is the visualization which shows the comparison among discrete categories. X axis of the chart shows the categories which are compared, and Y axis represents a measured value.

Here is the program for reference for **Bar Plot:**

**fig = plt.figure()**

**figure()** A function which is used to create a figure object.

**ax = fig.add_axes**

** **It is a figure module of matplotlib which is used to add axes to the figure.

**ax.bar()**

A module of matplotlib is used to make a bar plot.

**plt.show()**

Function to show the plot.

**HISTOGRAM:**

A histogram represents the numerical data. It is also known as the other form of Bar Graph.

Here is the program for the reference **Histogram:**

**np.array()**

A function which includes Array elements

**ax.hist()**

It is an essential function that is to plot a histogram graph.

**ax.set()**

A function which is know to be a property, In other words it is a batch setter, Be it Title set or a Label Set

**plt.show()**

A function to show the plot.

**PIE CHART:**

A Pie Chart displays one series of data. Pie charts shows the size of subjects in one data series in different divisions, The data points are shown in percentage in a Pie chart.

Here is the program for the reference **Pie Chart:**

**import numpy as np**

In simple terms making short “**numpy**” to “**np**” to make your code easier to read.

**fig = plt.figure()**

**figure()** A function which is to create a figure object.

**ax.pie**

A function of Matplotlib library which is to plot a pie chart Graph.

**plt.show()**

A function to show the plot.

Matplotlib – **Scatter Plot**

Scatter plots are knows to be of plotting data points on horizontal and vertical axis in the attempt to show how much one variable is affected by another.

A scatter plot is a diagram which is displayed in a graphical format where each value in the data set is represented by a single dot.

Here is a program for the reference **Scatter Plot:**

**fig = plt.figure()**

**figure()** A function which is to create a figure object.

**ax = fig.add_axes()**

To add the coordinates

**ax.scatter**

It is a module of Matplotlib library which is to plot a scatter plot graph.

**ax.set_title()**

To set the Title on the Top of the Graph

**CONTOUR PLOT**

Contour plots displays a 3 dimensional surface on 2 – dimensional plane.

Here is the program for the reference **Contour Plot:**

**np.linespace**

The **np**. **linspace** is a tool in Python for creating numeric sequences. It is kind of similar to np.arrange() function.

**np.meshgrid**

The `numpy.meshgrid`

function is used to create a rectangular grid out of two given 1 – dimensional arrays.

**np.sqrt**

A Function which is to determine the positive square-root of an array, in a specific way, element-wise.

**ax.contour**

It is a function of matplotlib is to Plot contours. **contour**draw contour lines.

**fig.colorbar(cp)**

It is a function of matplotlib is to add a color bar to a plot.

**ax.set_title()**

To set the Title on the Top of the Graph

**plt.show()**

A function to show the plot.

**QUIVER PLOT**

A quiver plot displays the velocity vectors as arrows with components.

Here is the program for the reference **Quiver Plot:**

**VIOLIN PLOT**

**Violin plots** are identical to box plots, exception is that they also show the probability density of the data at different pace of values.

A violin plot is much more informative than a plain box plot.

Here is the program for the reference **Violin Plot:**

**3 D CONTOUR PLOT**

** ax.contour3D() **

It is a function creates three-dimensional contour plot.

Here is the program for the reference **3D Contour Plot:**

**Output:**

**3D WIREFRAME PLOT**

Wireframe plot takes a grid of values and projects it onto the specified three-dimensional surface

Here is the program for the reference **3D Wireframe plot:**

**Output:**

**GRIDS**

The grid() function of axes object sets visibility of grid inside the figure to on or off.

Here is the program for the reference **Grids:**

**Output:**