實時動態掃描數據流

import datetime
import numpy as np
from matplotlib import pyplot as plt
import matplotlib.dates as mdates
plt.rcParams["font.sans-serif"]=['SimHei']
hour = 10
step = 60
second = int(float(hour)*60*60)
now = datetime.datetime.now()
MeanValue, SumValue, MeanIndex = 0, 0, 0
delta = datetime.timedelta(seconds=60)
xmin = now - delta
ymax = 0
plt.ion()
plt.figure(1)
ax = plt.subplot(111)
Meanline = []
for i in range(0, second, step):
    m = (1500 - 100 + 200 * np.random.random())/380
    if ymax < m:
        ymax = m
    now += delta
    SumValue += m
    xmax = now
    MeanValue = SumValue/(MeanIndex + 1)
    MeanIndex += 1
    if i == 0:
        x = [now - delta, now]
        y = [m-1, m]
        plt.plot(x, y, "-")
    else:
        x.pop(0)
        x.append(now)
        y.pop(0)
        y.append(m)
        plt.plot(x, y, "-")
    if (xmax - xmin) > datetime.timedelta(hours=1):
        xmin = xmax - datetime.timedelta(hours=1)
    plt.xlim(xmin, xmax)
    plt.ylim(0, 1.5*ymax)
    ax1 = plt.axhline(y=MeanValue, color="b", linewidth=1, linestyle="--")
    Meanline.append(ax1)
    if i > 1:
        Meanline[0].remove()
        Meanline.pop(0)

    plt.xticks(rotation=50)
    ax.xaxis.set_major_formatter(mdates.DateFormatter("%m-%d %H:%M:%S"))
    plt.pause(1)