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pythonmatplotlibheatmapcolorbarcalmap

How to draw a heatmap using calmap with the colorbar on the ax?


I have a pandas df as follows:

ipdb> df_calmap
                     count
start_datetime            
2021-03-10 17:40:24      1
2021-03-11 23:41:34      1
2021-03-12 00:41:42      1
2021-03-12 13:11:25      1
2021-03-15 00:02:49      1
2021-03-15 11:40:50      1
2021-03-17 12:42:14      1
2021-03-18 01:50:22      1
2021-03-21 19:10:55      1
2021-03-22 15:00:06      1
2021-03-25 00:22:22      1
2021-03-26 16:33:11      1
2021-03-29 19:16:59      1
2021-03-30 17:58:53      1
2021-03-31 17:46:08      1

I am able to draw a heatmap using calmap, however I would like to have the colorbar the same size as the image as shown here on a similar answer to my question. However, the code does not work for me. I don't seem to be able to achieve what I want.

image

I have searched the matplotlib doc but I couldn't make it work either. Here is my current code. Thank you very much.

def plot_trades_heatmap_chart(self):                                                                                                                                                          
    df_calmap = ...                                                                                                                                                                              
                                                                                                                                             
    fig, ax = calmap.calendarplot(df_calmap['count'], monthticks=1, daylabels='MTWTFSS',                                                                                                      
        dayticks=[0, 1, 2, 3, 4, 5, 6], cmap='RdYlGn',                                                                                                                                        
        fillcolor='whitesmoke', linewidth=0.3,                                                                                                                                                
        fig_kws=dict(figsize=(8, 4)))
                                                                                                                                                                                              
    # Vertical                                                                                                                                                                                
    fig.colorbar(ax[0].get_children()[1], ax=ax.ravel().tolist())                                                                                                                             
                                                                                                                                                                                              
    plt.xlabel("Trades grouped by day", fontsize=12)
    fig.suptitle('Number of trades per day heatmap', fontsize=16)
    return(fig)

The expected output should be like this: image

Thank you very much!


Solution

  • There was a great answer here, but it was a year plot. I tried to see if I could do the same thing with the calendar plot you wanted, but without success. So I made a few changes in the year plot and wrote the code in the calendar plot style.

    df_calmap.set_index('start_datetime', inplace=True)
    
    import matplotlib.pyplot as plt
    from mpl_toolkits.axes_grid1 import make_axes_locatable
    
    yyyy = 2021
    fig = plt.figure(figsize=(20,4))
    ax = fig.add_subplot(111)
                                                                                                 
    cax = calmap.yearplot(df_calmap['count'], year=yyyy)                                                                                                                                                                                           
    plt.xlabel("Trades grouped by day", fontsize=12)
    plt.ylabel(yyyy, fontsize=58, color='#f5f5f5', weight='bold')
    fig.suptitle('Number of trades per day heatmap', fontsize=16)
    
    divider = make_axes_locatable(cax)
    lcax = divider.append_axes("right", size="2%", pad=0.5)
    fig.colorbar(cax.get_children()[1], cax=lcax)
    

    enter image description here