Question

这是我的代码，我需要在橙色曲线上放置标记

halflife = 0.25
resolution_per_second = 1000
values = np.concatenate([np.zeros(resolution_per_second),
                         np.ones(resolution_per_second * 2),
                         np.zeros(resolution_per_second),
                         np.ones(resolution_per_second * 1),
                         np.zeros(resolution_per_second * 2),
                         ])
t_grid = np.arange(0, len(values)) / resolution_per_second
step = 1.0 / resolution_per_second
k = np.power(0.5, 1 / (halflife * resolution_per_second))

def ema_fixed_step(y, k): #ema method 1 on chart
    res = np.zeros_like(y)
    curV = y[0]
    for i in range(1, len(y) - 1):
        curV = k * curV + (1 - k) * y[i]
        res[i + 1] = curV
    return res

ema1_arr = ema_fixed_step(values, k)

#
w = values != np.roll(values, 1)
w[0] = True
t_new = t_grid[w]
values_new = values[w]
t_extra = [0.6, 1.0001, 1.2, 1.5, 2.9, 4.5, 3.3, 5.5]

t_req = np.sort(np.concatenate([t_new, t_extra]))


def ema_func2(t_req, t, y): #ema method 2 on chart
    return np.zeros_like(t_req, dtype=np.double)

ema2_arr = ema_func2(t_req, t_new, values_new)

plt.clf()
plt.step(t_grid, values, '.-', where='post', label='y')
plt.step(t_grid, ema1_arr, '.-', where='post', label='ema method 1')
plt.plot(t_req, ema2_arr, 'o', color='red', markersize=4, label='ema method 2')


plt.grid()
plt.legend()
plt.xlabel('t, seconds')

我有这个

我认为问题出在EMA2功能上，但我不明白如何按照我想要的方式进行编辑我将np.where设置为true，但没有成功我也尝试过使用数学，但仍然没有任何线索有什么建议吗？

Answer 1

您没有包括进口，但幸运的是我知道了它们
由于没有对应的点，我不得不从t_extra中删除一个值

也就是说，这就是我想出的

import numpy as np
import matplotlib.pyplot as plt

halflife = 0.25
resolution_per_second = 1000
values = np.concatenate([np.zeros(resolution_per_second),
                         np.ones(resolution_per_second * 2),
                         np.zeros(resolution_per_second),
                         np.ones(resolution_per_second * 1),
                         np.zeros(resolution_per_second * 2),
                         ])
t_grid = np.arange(0, len(values)) / resolution_per_second
step = 1.0 / resolution_per_second
k = np.power(0.5, 1 / (halflife * resolution_per_second))

def ema_fixed_step(y, k): #ema method 1 on chart
    res = np.zeros_like(y)
    curV = y[0]
    for i in range(1, len(y) - 1):
        curV = k * curV + (1 - k) * y[i]
        res[i + 1] = curV
    return res

ema1_arr = ema_fixed_step(values, k)

#
w = values != np.roll(values, 1)
w[0] = True
t_new = t_grid[w]
values_new = values[w]
t_extra = [0.6, 1.2, 1.5, 2.9, 4.5, 3.3, 5.5]

t_req = np.sort(np.concatenate([t_new, t_extra]))


def ema_func2(t_req, t, y): #ema method 2 on chart
    return np.zeros_like(t_req, dtype=np.double)

ema2_arr = ema_func2(t_req, t_new, values_new)

plt.clf()
plt.step(t_grid, values, '.-', where='post', label='y')
plt.step(t_grid, ema1_arr, '.-', where='post', label='ema method 1')

markers_y = []
for t in t_grid:
    if t in t_req:
        index = list(t_grid).index(t)
        markers_y.append(ema1_arr[index])

plt.scatter(t_req, markers_y, color='red', label='markers', zorder=10)

plt.grid()
plt.legend()
plt.xlabel('t, seconds')

plt.show()

输出：基本上，我只是列出一个列表，如果时间匹配，我会在适当的索引处获取y值（因为x和y必须具有相同的索引才能进行绘图）。然后我通过zorder=10

绘制了这些并确保它们是图表的顶层

我应该添加什么以在Matplotlib的橙色曲线上添加红色标记？

1 个答案: