Python中的三角形波阵列

Question

产生100个数字阵列的最有效方法是什么,形成下面的三角波形状,最大/最小振幅为0.5？

记住三角波形:

Answer 1

使用发电机:

def triangle(length, amplitude):
     section = length // 4
     for direction in (1, -1):
         for i in range(section):
             yield i * (amplitude / section) * direction
         for i in range(section):
             yield (amplitude - (i * (amplitude / section))) * direction

这对于可被4整除的长度可以正常工作,对于其他长度,您可能会错过最多3个值.

>>> list(triangle(100, 0.5))
[0.0, 0.02, 0.04, 0.06, 0.08, 0.1, 0.12, 0.14, 0.16, 0.18, 0.2, 0.22, 0.24, 0.26, 0.28, 0.3, 0.32, 0.34, 0.36, 0.38, 0.4, 0.42, 0.44, 0.46, 0.48, 0.5, 0.48, 0.46, 0.44, 0.42, 0.4, 0.38, 0.36, 0.33999999999999997, 0.32, 0.3, 0.28, 0.26, 0.24, 0.21999999999999997, 0.2, 0.18, 0.15999999999999998, 0.14, 0.12, 0.09999999999999998, 0.08000000000000002, 0.06, 0.03999999999999998, 0.020000000000000018, -0.0, -0.02, -0.04, -0.06, -0.08, -0.1, -0.12, -0.14, -0.16, -0.18, -0.2, -0.22, -0.24, -0.26, -0.28, -0.3, -0.32, -0.34, -0.36, -0.38, -0.4, -0.42, -0.44, -0.46, -0.48, -0.5, -0.48, -0.46, -0.44, -0.42, -0.4, -0.38, -0.36, -0.33999999999999997, -0.32, -0.3, -0.28, -0.26, -0.24, -0.21999999999999997, -0.2, -0.18, -0.15999999999999998, -0.14, -0.12, -0.09999999999999998, -0.08000000000000002, -0.06, -0.03999999999999998, -0.020000000000000018]

Answer 2

生成三角波的最简单方法是使用signal.sawtooth.请注意,signal.sawtooth(phi,width)接受两个参数.第一个参数是阶段,下一个参数指定对称性.width = 1给出一个右边的锯齿,width = 0给出一个左边的锯齿,width = 0.5给出一个对称的三角形.请享用!

from scipy import signal
import numpy as np
import matplotlib.pyplot as plt
t = np.linspace(0, 1, 500)
triangle = signal.sawtooth(2 * np.pi * 5 * t, 0.5)
plt.plot(t, triangle)

Answer 3

要使用numpy:

def triangle2(length, amplitude):
    section = length // 4
    x = np.linspace(0, amplitude, section+1)
    mx = -x
    return np.r_[x, x[-2::-1], mx[1:], mx[-2:0:-1]]

Answer 4

三角形是锯齿的绝对值。

from scipy import signal
time=np.arange(0,1,0.001)
freq=3
tri=np.abs(signal.sawtooth(2 * np.pi * freq * time))