Sample code for Heatmap generation : use case emailing visualisation profile

heatmap_toolkit.py

# https://medium.com/@shuvashish.chatterjee/putting-graphs-inside-emails-bb6dfc16553c
import matplotlib.cm as cm
import matplotlib.colors as colors
import pandas as pd
import numpy as np

d = np.random.randint(0,20,size=(8,7))
df = pd.DataFrame(data =d,columns=['Mon','Tue','Wed','Thur','Fri','Sat','Sun'])


def heatmapHtml(df):
    cmap = cm.get_cmap('summer')    
    cmap.set_bad('white',1.)
    nrows, ncolumns = df.shape
    minimum = np.nanmin(df.values)
    maximum = np.nanmax(df.values)
    norm = colors.Normalize(vmin=minimum, vmax=maximum)
    table=""" <style>
                .value{ margin: 0px;display: none;padding: 0px; }
                .label{  margin: 0px; padding: 0px;  }
                .cell:hover>.value{ display: inline-block; }
                .table{table-layout:fixed;width:100%; min-width: 400px;height: 50%;min-height: 400px;}
                .ylabel{padding: 0px;cursor:pointer;opacity: 0.8;width: 10px;height: 10px;text-align: center;}
            </style>
    
                <table class="table" table-layout="fixed" border="0">
                <thead>
                    <tr>
                    <th  width="15%"> <h6 class="label" ></h6></th>"""
    for c in range(ncolumns):
        table = table + """ <th> <h6 class="label" >"""+str(df.columns[c]) +  """</h6></th>   """        
    table = table + """   </tr></thead><tbody> """   
    for r in range(nrows):
        table= table + """<tr> <td class="ylabel" > <h6 class = "label"> """ + str(df.index[r]) + """</h6></td> """
        for c in range(ncolumns):
            value= df.iloc[r,c]
            if np.isnan(value):
                hexcode="#ffffff"
#                print value, c
            else:
                hexcode =colors.rgb2hex(cmap(norm(  value    )))
            table=table + """<td style="background:""" + hexcode + """;" class="cell" ><h6 class = "value">"""+ str(value)+ """</h6></td>"""
        table = table+ """ </tr> """
    table = table + """ </tbody></table> """
    hexmin=colors.rgb2hex(cmap(norm(  minimum    )))
    hexmid=colors.rgb2hex(cmap(norm(  (minimum + maximum)/2   )))
    hexmax=colors.rgb2hex(cmap(norm(  maximum    )))
    mid = str(int(round((minimum + maximum)/2)) )
    maximum =str(int(round( maximum)) )
    minimum =str(int(round( minimum)) )
    full="100%"
    quarter="25%"
    table=table+ """
            <hr>
            <table width="%(full)s">
                <tr width = "%(full)s"  height ="10">
                    <td  style="width: %(quarter)s"> <h6 style="margin:2px;"> Legend</h6></td>
                    <td style="background: %(hexmin)s; width: %(quarter)s; color:white;"><h6 style="margin:2px;">Minimum %(minimum)s</h6></td>
                    <td style="background: %(hexmid)s; width: %(quarter)s"><h6 style="margin:2px;">Average %(mid)s</h6></td>
                    <td style="background: %(hexmax)s; width: %(quarter)s"><h6 style="margin:2px;">Maximum %(maximum)s</h6></td>
                </tr>
            </table>
    """ % { "minimum":minimum , "maximum":maximum , "mid":mid , "hexmin":hexmin , "hexmid":hexmid , "hexmax":hexmax, "quarter" :quarter , "full" :full  }
    return table
    
  table  = heatmapHtml(df)