Plot Data from MySQL in Python/v3
How to graph data from a MySQL database with Python.
See our Version 4 Migration Guide for information about how to upgrade.
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Version Check¶
Plotly's python package is updated frequently. Run pip install plotly --upgrade
to use the latest version.
import plotly
plotly.__version__
Imports¶
This notebook uses the MySQL world database:http://dev.mysql.com/doc/index-other.html. Instructions for setting up the world database in MySQL are here. This notebook was created for this article in Modern Data
import plotly.plotly as py
import plotly.graph_objs as go
import MySQLdb
import pandas as pd
Connect to MySQL Database¶
conn = MySQLdb.connect(host="localhost", user="root", passwd="xxxx", db="world")
cursor = conn.cursor()
cursor.execute('select Name, Continent, Population, LifeExpectancy, GNP from Country');
rows = cursor.fetchall()
str(rows)[0:300]
df = pd.DataFrame( [[ij for ij in i] for i in rows] )
df.rename(columns={0: 'Name', 1: 'Continent', 2: 'Population', 3: 'LifeExpectancy', 4:'GNP'}, inplace=True);
df = df.sort_values(['LifeExpectancy'], ascending=[1]);
Some country names cause serialization errors in early versions of Plotly's Python client. The code block below takes care of this.
country_names = df['Name']
for i in range(len(country_names)):
try:
country_names[i] = str(country_names[i]).decode('utf-8')
except:
country_names[i] = 'Country name decode error'
trace1 = go.Scatter(
x=df['GNP'],
y=df['LifeExpectancy'],
text=country_names,
mode='markers'
)
layout = go.Layout(
title='Life expectancy vs GNP from MySQL world database',
xaxis=dict( type='log', title='GNP' ),
yaxis=dict( title='Life expectancy' )
)
data = [trace1]
fig = go.Figure(data=data, layout=layout)
py.iplot(fig, filename='world GNP vs life expectancy')
# (!) Set 'size' values to be proportional to rendered area,
# instead of diameter. This makes the range of bubble sizes smaller
sizemode='area'
# (!) Set a reference for 'size' values (i.e. a population-to-pixel scaling).
# Here the max bubble area will be on the order of 100 pixels
sizeref=df['Population'].max()/1e2**2
colors = {
'Asia':"rgb(255,65,54)",
'Europe':"rgb(133,20,75)",
'Africa':"rgb(0,116,217)",
'North America':"rgb(255,133,27)",
'South America':"rgb(23,190,207)",
'Antarctica':"rgb(61,153,112)",
'Oceania':"rgb(255,220,0)",
}
# Define a hover-text generating function (returns a list of strings)
def make_text(X):
return 'Country: %s\
<br>Life Expectancy: %s years\
<br>Population: %s million'\
% (X['Name'], X['LifeExpectancy'], X['Population']/1e6)
# Define a trace-generating function (returns a Scatter object)
def make_trace(X, continent, sizes, color):
return go.Scatter(
x=X['GNP'], # GDP on the x-xaxis
y=X['LifeExpectancy'], # life Exp on th y-axis
name=continent, # label continent names on hover
mode='markers', # (!) point markers only on this plot
text=X.apply(make_text, axis=1).tolist(),
marker= dict(
color=color, # marker color
size=sizes, # (!) marker sizes (sizes is a list)
sizeref=sizeref, # link sizeref
sizemode=sizemode, # link sizemode
opacity=0.6, # (!) partly transparent markers
line= dict(width=3,color="white") # marker borders
)
)
# Initialize data object
data = []
# Group data frame by continent sub-dataframe (named X),
# make one trace object per continent and append to data object
for continent, X in df.groupby('Continent'):
sizes = X['Population'] # get population array
color = colors[continent] # get bubble color
data.append(
make_trace(X, continent, sizes, color) # append trace to data object
)
# Set plot and axis titles
title = "Life expectancy vs GNP from MySQL world database (bubble chart)"
x_title = "Gross National Product"
y_title = "Life Expectancy [in years]"
# Define a dictionary of axis style options
axis_style = dict(
type='log',
zeroline=False, # remove thick zero line
gridcolor='#FFFFFF', # white grid lines
ticks='outside', # draw ticks outside axes
ticklen=8, # tick length
tickwidth=1.5 # and width
)
# Make layout object
layout = go.Layout(
title=title, # set plot title
plot_bgcolor='#EFECEA', # set plot color to grey
hovermode="closest",
xaxis=dict(
axis_style, # add axis style dictionary
title=x_title, # x-axis title
range=[2.0,7.2], # log of min and max x limits
),
yaxis=dict(
axis_style, # add axis style dictionary
title=y_title, # y-axis title
)
)
# Make Figure object
fig = go.Figure(data=data, layout=layout)
# (@) Send to Plotly and show in notebook
py.iplot(fig, filename='s3_life-gdp')
References¶
See https://plotly.com/python/getting-started/ for more information about Plotly's Python Open Source Graphing Library!