Python Pandas DataFrame plot to draw line graphs with options

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Pandas plot

Pandas.DataFrame.plot to get line graphs using data

Let us create a DataFrame with name of the students and their marks.

import pandas as pd 
my_dict={
	'NAME':['Ravi','Raju','Alex','Ron','Geek','Kim'],
	'MARK':[20,30,40,30,40,50]
	}
my_df = pd.DataFrame(data=my_dict)
print(my_df)

Output is here

   NAME  MARK
0  Ravi    20
1  Raju    30
2  Alex    40
3   Ron    30
4  Geek    40
5   Kim    50

Line Graph

import pandas as pd 
my_dict={
'NAME':['Ravi','Raju','Alex',
        'Ron','Geek','Kim'],
'MARK':[20,30,40,30,40,50]
}
df = pd.DataFrame(data=my_dict)
df.plot.line(title="Std Mark");

Options

There are several options we can add to above plot. We will discuss them here. Before that let us try some of the options for our line graph.

import pandas as pd 
my_dict={
'NAME':['Ravi','Raju','Alex',
        'Ron','Geek','Kim'],
'MARK':[20,30,40,30,40,50]
}
df = pd.DataFrame(data=my_dict)
my_style=['-.']
df.plot.line( title="Student Mark",figsize=(6,3),x='NAME',y='MARK',
use_index=True,grid=True,legend=True,style=my_style)

title :

title='Student Mark' String used as Title of the graph. We can also use one list to give titles to sub graphs. ( for this subplot must be true )

figsize :

Size of the graph , it is a tuple saying width and height in inches, figsize=(6,3). Here width is 6 inches and height is 3 inches.

X: Y:

What is to be used in X and Y axis. If you have multiple keys then you can specify what can be used. Note that Y axis must be numeric data to plot the graph.
Example : Here we have used y='ENGLISH' to plot the graph against the name of students ( x='NAME' )

import pandas as pd 
my_dict={
'NAME':['Ravi','Raju','Alex',
        'Ron','Geek','Kim'],
'MARK':[20,30,40,30,40,50],
'ENGLISH':[80,70,60,70,90,80]    
}
df = pd.DataFrame(data=my_dict)
df.plot.line( title="Student Mark",x='NAME',y='ENGLISH',use_index=True,legend=True)

use_index

True or False ( default is True ) , To show index or not. The difference is mentioned here ( check X - axis ) .
use_index=True option

grid

We will show grid ( grid=True ) or not ( grid=False) grid=True option

legend

True of False ( default is True ), to show legend ( legend=True ) or not ( legend=False)
legend=True option

style

This is a list or dict. We can specify how the style of the line.

my_style=[':']
df.plot.line( title="style =[ ':'] ",x='NAME',style=my_style)

logx logy loglog

We can specify log scaling or symlog scaling for x ( logx=True ) or y ( logy=True ) or for both x & y ( loglog=True)

df.plot.line( title="loglog=True",figsize=(5,3),loglog=True)

secondary_y

Whether to plot on secondary Y Axis ( secondary_y=True ) or not ( secondary_y=False )

mark_right

Check the image above when secondary_y=True. There is a automatic marking in column lebels saying (right). We can manage this to show ( mark_right=True) or not ( mark_right=False)

df.plot.line( title="secondary_y=True",x='NAME',figsize=(5,3),secondary_y=True)

rot

Rotation of ticks ( check the names at x axis )
rot=45

df.plot.line( title="rot=180",x='NAME',figsize=(5,3),rot=180)

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