Handling of data is a skillful art. In the trending technological world there is massive amount of data that is being consumed as well as wasted. But, handling these data in a rather effective manner, becomes the main goal of data science. We can make use of various programming languages to deal with the datasets that require operations to be done on them, like- calculating the statistics, sales, marketing, plotting on graphical platforms, etc.
The following content will enable you to get a detailed view on how data can be plotted using matplotlib.
Plotting of data can be extensively made possible in an interactive way by matplotlib, which is a plotting library that can be demonstrated in python scripts. Plotting of graphs is a part of data virtualization hence, this property can be achieved by making use of matplotlib.
Matplotlib makes use of many general purpose GUI toolkits such as wxPython, Tkinter, Qt, etc. in order to provides an object oriented API for embedding plots into applications. John D. Hunter was the person who originally wrote matplotlib. And its lead developer is Michael Droettboom. One of the free and open source python library which is basically used for technical and scientific computing is SciPy. Matplotlib is used in SciPy as most scientific calculations may require plotting of graphs and diagrams.
|It is an open source programming language, free to use||MATLAB is a commercial based platform. Hence, it is not free.|
|Matplotlib is more flexible and capable for plotting||Plotting is comparatively not as flexible and capable as python plotting.|
|Python provides a large number of libraries to work with.||It is tricky to add libraries and then work with in MATLAB|
|Python is an easy to read and powerful programming language||MATLAB is not as powerful as python|
|Matplotlib plotting is faster in python||Plotting of data requires time and effort.|
|Integrated development environment(IDE) need to be added additionally||IDE shall be provided within the MATLAB environment|
|Code can be used in multiple systems. It is portable||Code portability is restricted|
|Namespace is supported in python||Core of MATLAB does not support namespace|
The graph can be used to plot three straight lines. Hence, we make this possible by using the plotting library matplotlib.
1. Plot: Illustration that can be represented using a graph
When we take the plot parameters as [1,1] we get the above represented plot as the output.
2. Figure: A diagram or a shape that can be formed by a collection of plots in different dimensions
Example for figure():
3. Label: It is used to add labels or name to the respective x and y axis
4. Title: Used to display the title of the graph
Example for label() and title()
In the above graph the horizontal axis is labelled as X-axis and the vertical axis is labelled as Y-axis and the title is displayed as GRID REPRESENTATION.
5. Grid: It is a collection of objects and functions which is concerned with 3 dimensional data.
Example for grid
A grid based representation is displayed in the above output and this helps to locate specific regions in the graph.
6. Subplot: A function subplot() can be called to plot multiple plots in the same figure.
Example for subplot
There are various plotting techniques or ways of plotting that can be carried out on the data provided and some of these plotting types are-
The plotting of a frequency of data along a line can be represented using line plot. It is one of the simplest and commonly used plotting methods. Line plotting is a primitive plotting technique that we have been using as it was the first plotting method that was introduced.
Let us now look at a real time scenario:
Consider a survey to be done on how much distance the following vehicles have covered in a span of 5 days. And the data collected can be plotted in different plotting methods.
I have made use of jupyter notebook to run the codes to represent the following data in plots.
DISTANCE COVERED IN KMS
Example for line plot
Various lines are represented in the above graph and each line is denoted with a unique color. The line representing Honda has been overwritten upon by the line representing KTM since, both the vehicles have covered same distance in their respective days.
Categorical data can be represented in rectangular blocks with different height and length proportional to the values. Such a type of representation is called a bar chart. Bar charts can be used to plot data in both vertical and horizontal manner.
Example for Bar plot
The above plotting shows the bar representation of the given scenario where the mentioned bikes are symbolized using different colors and each colored block shows the distance covered by the respective bikes on every particular day for a period of 5 days.
This type of plotting is basically used for quantitative data. Line chart forms the basis of an area plot where, the region between the axis and the line is represented by colors.
Example of area plot
The above represented graph shows how an area plot can be plotted using the bike and its distance covered scenario. Each shaded area in the graph shows a particular bike with the frequency variations denoting the distance covered by the bike on different days.
Statistical data can be represented in a circular graph where the circle is divided into portions that denote particular data, that is, each portion can be called a slice and these slices are proportional to the values in the data. This sort of plot can be mainly used in mass media and business.
Example for pie plot
Dot based plotting of multiple variables along x and y axis represent scatter plot. We can use different colors if necessary for better plotting and identification of dots.
Example for scatter plot
Plotting of data along the X, Y and Z -axis to enhance the display of data and get a better view of plotted data, represents the three dimensional plotting. A three dimensional plotting is an advanced plotting technique that gives us a better view of the data representation along the three axis of the graph.
Example for 3d plot
In the above represented 3 dimensional graph. A line graph is illustrated in a three dimensional manner. We make use of a special library to plot 3D graphs which is given in the following syntax.
Syntax for plotting 3D graphs
The import Axes3D is mainly used to create an axis by making use of the projection=3d keyword. This enables a three dimensional view of any data that can be written along with the above mentioned code.
The plotting of numerical data in a precise manner by using rectangular blocks forms the basis of histogram plotting. A probability distribution can be estimated using histogram plot. The data is mostly represented in a continuous manner based on the dataset provided to plot the graph.
Example for histogram plot
The represented graph of a histogram shows the stepfill pattern. There are various histypes that can be used such as, bar, step, stepfill, etc. Histogram does not include spaces between the blocks. It is a continuous structure denoting the distance count that is the number of times the same distance is covered within a span of five days by the bikes along the Y-axis and the kilometer distance along X-axis.
This tutorial has shown you how to work with matplotlib and how to implement various types of plotting techniques. Hopefully, this tutorial served as a good demonstration about what is possible by using matplotlib. Dealing with multiple or huge amount of data and representing them in graphs for better understanding shows a beneficial use of matplotlib in python.
From code representation to output generation and explaining the graphs have been carried out in the tutorial. So, I would suggest you to go through the examples and practice them to get a better insight on how the code works.
Learning to work in python by using matplotlib shall enable you to improve in quality assessment of various data that can be put in front of you to deal with. This shall ensure you to become successful in the domain of plotting data.
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