Ch 3 Plotting with PyPlot
Sumita Arora Book Exercise Solution
Type A: Short Answer Questions / Conceptual Questions
1. Name the library of which the PyPlot is an interface.
Ans: Matplotlib
2. Write the statement to import PyPlot in your script.
Ans: import matplotlib.pyplot
OR
import matplotlib.pyplot as plt
3. Name the functions to create the following:
(a) line chart (b) bar chart (c) horizontal bar chart (d) histogram
(e) scatter chart (t) boxplot (g) pie chart
Ans: (a) plot( )
(b) bar( )
(c) barh( )
(d) hist( )
(e) scatter( ) or plot( )
(f) boxplot( )
(g) pie( )
4. What is a line chart?
Ans: Line Chart is a type of chart which displays information as a series of data points called ‘markers’ connected by straight line segments. A plot( ) function is used to make line chart.
5. What is a scatter chart?
Ans: Scatter chart is a graph of plotted points on two axes that show the relationship between two sets of data. A scatter( ) method of pyplot interface is use to make the scatter chart. A scatter chart can be created by using plot( ) method also.
6. What is a pie chart?
Ans: Pie chart is a type of chart or graph in which a circle is divided into sections that each represent a proportion of the whole. A pie() method of pyplot interface is use to make pie chart.
7. What is a bar chart?
Ans: Bar chart is a type of graph or chart, which represent the numerical data graphically using bars of different height. It can draw vertically or horizontally. A bar() and barh( ) method of pyplot interface is use to create bar chart.
8. What is a histogram?
Ans: Histogram is a summarisation tool for discrete or continuous data.
9. What is a boxplot?
Ans: A histogram is basically used to represent data provided in a form of some groups. It is accurate method for the graphical representation of numerical data distribution.
10. What is a frequency polygon?
Ans: Frequency polygon is a type of frequency distribution graph. In this, number of observations is marked with a single point at the midpoint of an interval. A straight line then connects each set of points.
11. Name the function to label axes.
Ans: xlabel( ) and ylabel( )
12. Name the function to give a title to a plot.
Ans: title( )
13. Name the function to set figure size of a plot.
Ans: figure(figsize=(w, l))
14. Name the function to set limits for the axes.
Ans: matplotlib.pyplot.xlim( ), matplotlib.pyplot.ylim( )
15. Name the function to show legends on a plot.
Ans: matplotlib.pyplot.legend(loc=value)
or
plt.legend()
16. Name the function to add ticks on axes.
Ans: For x-axis:
matplotlib.pyplot.xticks(sequence tick data points [, sequence tick lable])
For y-axis:
matplotlib.pyplot.yticks(sequence tick data points [, sequence tick lable])
