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Matplotlib

Programming / python

Hello matplotlib

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import matplotlib.pyplot as plt
import numpy as np 

fig, ax = plt.subplots()             # Create a figure containing a single Axes.
ax.plot([1, 2, 3, 4], [1, 4, 2, 3])  # Plot some data on the Axes.
plt.show()

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Figure

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The whole figure. The Figure keeps track of all the child Axes, a group of 'special' Artists (titles, figure legends, colorbars, etc.), and even nested subfigures.

Axes

An Axes is an Artist attached to a Figure that contains a region for plotting data, and usually includes two (or three in the case of 3D) Axis objects

Axis

Artist

3D plot

Animation

Embedded in QT

figure and subplots

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import matplotlib.pyplot as plt
import numpy as np 

fig, axs = plt.subplots(2, 2, figsize=(4, 3), layout='constrained')
for row in range(2):
    for col in range(2):
        axs[row, col].annotate(f'axs[{row}, {col}]', (0.5, 0.5),
                            transform=axs[row, col].transAxes,
                            ha='center', va='center', fontsize=18,
                            color='darkgrey')
# ax.plot([1, 2, 3, 4], [1, 4, 2, 3])  # Plot some data on the Axes.
plt.show()

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import matplotlib.pyplot as plt
import numpy as np

fig, axs = plt.subplots(2, 2, figsize=(4, 3), layout="constrained")

x, y = [1, 2], [4, 5]

ax = axs[0, 0]
linesx = ax.scatter(x, y)

ax = axs[0, 1]
linesx = ax.plot(x, y)

ax = axs[1, 0]
linesx = ax.bar(x, y)

ax = axs[1, 1]
img_2d_array = np.random.rand(10, 10)
linesx = ax.imshow(img_2d_array)

plt.show()

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