TIL: Defining a piecewise function in numpy

python/defining-a-piecewise-function-in-numpy.md

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+This is how you can define a piecewise function in numpy:
+
+```python
+import numpy as np
+import matplotlib.pyplot as plt
+
+
+def piecewise(t):
+    conds = [ 
+        t <= -1, 
+        (-1 < t) & (t <= 1),
+        (1 < t) & (t <= 5),
+        t > 5
+    ]
+    funcs = [
+        lambda t: 0, 
+        lambda t: t + 1, 
+        lambda t: 4 - 2*t, 
+        lambda t: 0
+    ]
+    return np.piecewise(t, conds, funcs)
+
+t = np.arange(-2, 6, 0.01)
+plt.xlabel('t')
+plt.ylabel('y(t)')
+plt.plot(t, piecewise(t))
+plt.show() # or plt.savefig('my_fig.png')
+```