Create a poster with matplotlib to visualize multiplication tables that remember multiplication

There is a "multiplication table", isn't it? This is the one when children learn multiplication in Japan.

"Inichi gaichi, innigani, insan gasan," is the one.

The multiplication table is convenient for learning multiplication, but I heard the opinion that "You can't just remember the pun. You have to understand the meaning of multiplication." So I made a poster that can understand the meaning of multiplication as well. I made it with matplotlib. It took about 30 minutes to code.

Installation and import of matploblib for Japanese

!pip install japanize-matplotlib

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import matplotlib.pyplot as plt
import japanize_matplotlib 

Drawing of multiplication table poster

fig, axes = plt.subplots(nrows=9, ncols=9, figsize=(16, 16))
for x in range(9):
    for y in range(9):
        axes[y][x].axis("off")
        axes[y][x].set_aspect("equal")
        axes[y][x].set_title("{} x {} = {}".format(x + 1, y + 1, (x + 1) * (y + 1)))
        axes[y][x].set_xlim([0, 11])
        axes[y][x].set_ylim([0, 11])
        X = []
        Y = []
        for i in range(x + 1):
            for j in range(y + 1):
                X.append(i + 2)
                Y.append(10 - j - 1)
        axes[y][x].scatter(X, Y)

plt.savefig("300_dpi_scatter.png ", format="png", dpi=300)

The order of multiplication?

By the way, it seems that teachers who care about the order of multiplication are talking about on Twitter etc., but is there anything to say about this?

Mouse version

My kids love the mice, so I made a mouse version as well.

fig, axes = plt.subplots(nrows=9, ncols=9, figsize=(28, 28))
for x in range(9):
    for y in range(9):
        axes[y][x].axis("off")
        axes[y][x].set_aspect("equal")
        axes[y][x].set_title("{} x {} = {}".format(x + 1, y + 1, (x + 1) * (y + 1)), fontsize=20)
        axes[y][x].set_xlim([-1, 11])
        axes[y][x].set_ylim([-1, 11])
        X = []
        Y = []
        for i in range(x + 1):
            for j in range(y + 1):
                X.append(i + 2)
                Y.append(10 - j - 1)
        if (x + 1) * (y + 1) % 2 == 1:
            c = 'k'
        else:
            c = 'r'
        axes[y][x].scatter(X, Y, c=c, s=28, marker='o')
        axes[y][x].scatter([xx + 0.25 for xx in X], [yy + 0.25 for yy in Y], c=c, s=12, marker='o')
        axes[y][x].scatter([xx - 0.25 for xx in X], [yy + 0.25 for yy in Y], c=c, s=12, marker='o')

plt.savefig("300_dpi_scatter.png ", format="png", dpi=300)

If the result of the multiplication is odd, I made it black, and if it was even, I made it red. Haha ♪