Seaborn/Matplotlib: how to remove the horizontal white lines that are overlaying the bars?

Question

This is how it looks:

I would like to remove the white lines that are overlaying the black bars. Btw: is it possible to remove the background behind the legend?

def stack():
    data1 = [

        0.7,
        0.8,
        0.3,
        0.6,
        0.5

    ]

    data2 = [

        20, 30, 23, 17, 28

    ]
    sns.set_theme()
    data = np.multiply(data1, 100)

    r = [0, 1, 2, 3, 4]

    fig, ax1 = plt.subplots()
    ax1.bar(r, data, color="black", width=.5)
    plt.ylim(0,100)
    plt.ylabel('Percent')
    plt.xlabel('Lineage')
    ax2 = ax1.twinx()
    ax2.bar(r, data2, color="red", width=.1)
    plt.ylim(0,150)
    plt.ylabel("Number")

    lgnd1 = mpatches.Patch(color="black", label='Percent')
    lgnd2 = mpatches.Patch(color="red", label='Number')
    plt.legend(loc='upper center',
               bbox_to_anchor=(0.5, 1.2),
               ncol=3, handles=[lgnd1, lgnd2])

    plt.savefig('number.svg', bbox_inches="tight", transparent=True)
    plt.show()

Answer 1

You can use the following code :

plt.grid(False)

Or if you still want the lines you can use:

plt.grid(zorder=0)
plt.bar(range(len(y)), y, width=0.3, align='center', color='skyblue', 
zorder=3)

Answer 2

Regarding the color of your legend: You chose this grey by setting the plot default to be the seaborn standard with sns.set_theme() (see seaborn.set_theme).

But, as described there, you are able to override every rc parameter ("runtime configuration parameter") Setting the legend background color to another color should be possible with using the parameter facecolor=... (see matplotlib.pyplot.legend, scroll down a bit )

In your case you can add this parameter here in your legend definition:

plt.legend(loc='upper center',
           facecolor='white',  # choose your background color
           bbox_to_anchor=(0.5, 1.2),
           ncol=3, handles=[lgnd1, lgnd2])