使用单个全局变量启动多个独立函数

Question

我确定我想错了，但我不知道如何走出死胡同。

我正在构建一个基于外部输入独立闪烁 LED 的程序。我的代码适用于单个 LED。然而，我能想到的让它适用于多个 LED 的所有方法似乎都很愚蠢。

基本上，我希望函数的所有实例都以相同的全局变量开始，但是一旦它们开始烹饪，它们就会按照自己的方式进行。这是当前代码的相关部分：

counter = 0
time_from_start = 0
new_average = 0

#eventually this will be get_new_average(sensor_number)
def get_new_average():
    #average is going to be time in .... ms?
    #eventually it will be the average from the arduino
    new_average = int(input("new average? "))

def lighter_up(light_number, intensity):
    print("lighter_up intensity = " + str(intensity))
    #this line needs to be modified to whatever the intensity should be
    strip.setPixelColorRGB(light_number, intensity, 0, 0)
    strip.show()
    return intensity + 1

def lighter_down(light_number, intensity):
    print("lighter_down value = " + str(255 - (intensity - 255)))
    #this line needs to be modified to whatever the intensity should be
    strip.setPixelColorRGB(light_number, 255 - (intensity - 255), 0, 0)
    strip.show()
    return intensity + 1

def heartbeat(light):
    #acknowledge that counter is a global variable
    global counter
    global start_time

    if counter == 0:
        get_new_average()
        #this counts seconds from an arbitrary start point
        start_time = int(time.perf_counter())
        counter = 1
    #the 255 value is arbitrary
    #need to change it when you figure out the flash
    elif 0 < counter < 255:
        counter = lighter_up(light, counter)
    elif 254 < counter <510:
        counter = lighter_down(light, counter)
    elif counter > 509:
        #turn off the light
        strip.setPixelColorRGB(light, 0, 0, 0)
        strip.show()
        #difference between the start time and now
        time_from_start = int(time.perf_counter()) - start_time
        print(time_from_start)
        #if the time from the start of the flash is less than the
        #duration of the heartbeat, as defiend by new_average
        if time_from_start < new_average:
            #just wait it out
            pass
        #if the time from start has hit the new_average
        #it is time for a new heartbeat
        elif time_from_start >= new_average:
            counter = 0
        else:
            print("There was an error in heartbeat()")
    else:
        print("error: counter = " + str(counter))
while True:
    heartbeat(0)

我想在末尾添加一个heartbeat(1) 来控制最终将连接到第二个传感器的第二个灯。但是，这样做会使 heartbeat(0) 中的“计数器”和 heartbeat(1) 中的“计数器”发生冲突（并且对 time_from_start 和 new_average 产生相同的影响）。

我可以创建一个全局变量列表（“counter0”、“counter1”等），但这看起来既愚蠢又不优雅。我也可以在 heartbeat() 中移动计数器，但是每次循环时它都会重置为零，并且什么都不会发生。一定有更好的办法！

我强烈怀疑（希望？）这是一个完全常见的 python 东西，有一个非常明显的解决方案。我就是找不到。有什么想法吗？

谢谢

Answer 1

如果我理解正确，您正在寻找的是一种为每个“灯”设置不同的变量集 counter、time_from_start 和 new_average 的方法，这样您就可以将函数分别应用于每个灯没有函数覆盖其他“灯”自己的变量集？

如果是，pythonic 的解决方案是定义一个类并为每个灯光创建一个实例。然后，您的函数将成为该类的方法，并且每个实例都有自己的状态（变量集）：

class Light(object):
    def __init__(self, number):
       self.number = number
       self.counter = 0
       self.time_from_start = 0
       self.new_average = 0

    def get_new_average(self):
        self.new_average = int(input("new average? "))

    def lighter_up(self, intensity):
        print("lighter_up intensity = " + str(intensity))
        #this line needs to be modified to whatever the intensity should be
        strip.setPixelColorRGB(self.number, intensity, 0, 0)
        strip.show()
        return intensity + 1

    def lighter_down(light_number, intensity):
        print("lighter_down value = " + str(255 - (intensity - 255)))
        #this line needs to be modified to whatever the intensity should be
        strip.setPixelColorRGB(self.number, 255 - (intensity - 255), 0, 0)
        strip.show()
        return intensity + 1

    def heartbeat(self):
        if self.counter == 0:
            self.get_new_average()
            #this counts seconds from an arbitrary start point
            start_time = int(time.perf_counter())
            self.counter = 1

        #the 255 value is arbitrary
        #need to change it when you figure out the flash
        elif 0 < self.counter < 255:
            self.counter = self.lighter_up(self.counter)
        elif 254 < self.counter <510:
            self.counter = self.lighter_down(self.counter)
        elif counter > 509:
            #turn off the light
            strip.setPixelColorRGB(light, 0, 0, 0)
            strip.show()
            #difference between the start time and now
            self.time_from_start = int(time.perf_counter()) - start_time
            print(self.time_from_start)
            #if the time from the start of the flash is less than the
            #duration of the heartbeat, as defiend by new_average
            if self.time_from_start < self.new_average:
                #just wait it out
                pass
            #if the time from start has hit the new_average
            #it is time for a new heartbeat
            elif self.time_from_start >= self.new_average:
                self.counter = 0
            else:
                print("There was an error in heartbeat()")
        else:
            print("error: counter = " + str(self.counter))


lights = [Light(0), Light(1)]
while True:
   for light in lights:
       light.heartbeat()