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Created by Unknown User (jonakaa), last modified on 13.06.2019
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Simple plot
import numpy as np
import matplotlib.pyplot as plt
# Evenly sampled time from 0s to 10s at 200ms intervals
t = np.arange(0.0, 10.0, 0.2)
# Plotting t at x-axis and sin(t) at y-axis
plt.plot(t, np.sin(t))
# Naming the title and both axis
plt.title('Sinus function')
plt.ylabel('sin(t)')
plt.xlabel('t [s]')
# Need to call the show() function at the end to display my figure
plt.show()
import numpy as np
import matplotlib.pyplot as plt
# Evenly sampled time at 200ms intervals
t = np.arange(0.0, 5.0, 0.2)
# plot() can plot several lines in the same figure. To seperate the different lines
# from eachother, we may change the line style and format strings.
# See the plot() documentation for a complete list of line styles and format strings.
# The following lines have red dashes, blue squares and green triangles
plt.plot(t, t, 'r--', label='Linear line')
plt.plot(t, t**2, color='blue', linestyle='none', marker='s', label='Second degree polynom')
plt.plot(t, t**3, 'g^', label='Third degree polynom')
# To describe our plot even more detailed we can draw the labels we previously gave our lines using legend.
plt.legend(loc='upper left')
# The function axis() sets the axis sizes, and takes the argument [xmin, xmax, ymin, ymax]
plt.axis([0, 5, 0, 100])
plt.title('Mulitple polynoms')
plt.show()
import matplotlib.pyplot as plt
import numpy as np
# Some example data to display
x = np.linspace(0, 2 * np.pi, 400)
y = np.sin(x ** 2)
A single plot
subplots() without arguments return a Figure and a single Axes.
fig, ax = plt.subplots()
ax.plot(x, y)
ax.set_title('A single plot')
Quiver plot
import numpy as np
import matplotlib.pyplot as plt
# X and Y define the arrow locations
X, Y = np.meshgrid(np.arange(0, 2 * np.pi, .2), np.arange(0, 2 * np.pi, .2))
# U and V define the arrow directions, respectively in x- and y-direction
U = np.cos(X)
V = np.sin(Y)
# Call signature: quiver([X, Y], U, V, [C]), where C optionally sets the color
plt.quiver(X, Y, U, V)
plt.title('Simple quiver plot')
plt.show()
import numpy as np
import matplotlib.pyplot as plt
# X and Y define the arrow locations
# This setup gives us 10 arrows in width and height, as our interval is from -5 to 5 with step 1
X = np.arange(-5, 5, 1)
Y = np.arange(-5, 5, 1)
# U and V define the arrow directions, respectively in x- and y-direction
U, V = np.meshgrid(3*X, 3*Y)
plt.figure()
plt.subplot(121)
plt.quiver(X, Y, U, V)
plt.title('Only autoscaling')
plt.subplot(122)
plt.quiver(X, Y, U, V)
# Here we specify the axes. How much extra space you need depends on the arrow size and direction,
# and must therefor be adapted each time
plt.axis([-6.5, 5.5, -6.5, 5.5])
plt.title('Manually set axes')
plt.show()