有没有更好的方法来平均两个温度传感器输入？

Question

I'm building an overhead console for my car. I want to display the temperature outside using the average reading from two temp sensors. I am currently using Timo's Library and am able to retrieve temperatures from each sensor. When I try to average or convert the temps, nothing happens when I run the code except for a blinking cursor. I am new to python.

I have tried adjusting my definitions, the order in which statements are entered, I have changed the locations of the statements from inside the if statements to outside. Hoping its something that I missed. I apologize ahead of time if my question is not formatted correctly.

import os
import time
import serial
from w1thermsensor import W1ThermSensor

os.system('modprobe w1-gpio')
os.system('modprobe w1-therm')

#---------------------------------------------------------
#  Define the function to convert Celsius to Fahrenheit
#---------------------------------------------------------

def CelsiusToFahrenheit(TempCelsius):
 TempFahrenheit = ((TempCelsius*9)/5) + 32
 return TempFahrenheit

#----------------------------------------------------------
#  Define function to Average Outside Temperature in Fahrenheit
#----------------------------------------------------------

def OutsideTempAvg(A, B):
  OutsideTemp = (A + B)/2
  return OutsideTemp

#----------------------------------------------------------
#  Set Pointer to W1ThermSensor object
#----------------------------------------------------------

TmpSensor = W1ThermSensor()

#----------------------------------------------------------
#  Define Sensors by ID
#----------------------------------------------------------

Fsensor = '03079779c963'
Rsensor = '03159779fe5a'
Isensor = '030797799182'

#----------------------------------------------------------
#  Loop Through Available Sensors Identify and Assign 
#----------------------------------------------------------
while True:

    for TmpSensor in W1ThermSensor.get_available_sensors():
        CurSensorID = TmpSensor.id
        CurTempC = round(float(TmpSensor.get_temperature()),1)

        if CurSensorID == Fsensor:
            FtempC = CurTempC
        elif CurSensorID == Rsensor:
            RtempC = CurTempC
        elif CurSensorID == Isensor:
            ItempC = CurTempC
        else:
            print("Unexpected Sensor = " + CurSensorID)
            print("Temp = " + str(FtempC))
            print("Temp = " + str(RtempC))
            print("Temp = " + str(ItempC))

#----------------------------------------------------------------
#  Average and Convert Celsius to Fahrenheit
#----------------------------------------------------------------

            OtempC = round(float(OutsideTempAvg(FtempC, RtempC)))
            OtempF = round(float(CelsiusToFahrenheit(OtempC)))
            FtempF = round(float(CelsiusToFahrenheit(FtempC)))
            RtempF = round(float(CelsiusToFahrenheit(RtempC)))
            ItempF = round(float(CelsiusToFahrenheit(ItempC)))

#-----------------------------------------------------------------
#  Print for testing - Final will be sent to HMI display over Serial
#------------------------------------------------------------------     

            print("Outside Temperature = " + str(OtempF) + " Fahrenheit")
            print("Inside Temperature = " + str(ItempF) + " Fahrenheit")

#---------------------------------------------------------------------
#  Reset time - Final will be 5 minutes
#----------------------------------------------------------------------

    time.sleep(5.0)

I want to be able to print the readings, in both C and F, from each sensor and the average from two of them (Fsensor and Rsensor). Eventually I will send the results out of the serial interface of the Pi to an HMI LCD.

Answer 1

I think you have an issue with indentation:

while True:
    for sensor in W1ThermSensor.get_available_sensors():
        if some_condition:
            pass
        elif some_other_condition:
            pass
        else:  # unreal case just to handle all possible cases
            print('this is not printed when everything is ok')

            calculcate1()  # this function is called only if above is printed!

    calculate2()  # <-- move all calculation to the same level as "for" loop.

side note:

• Python allow to init variables as you go, but it is your responsibility that variables are initialized before accessed! Imaging that Rsensor was not available on "for" loop, your RtempC would never be initialized. To address it - simply create variables ahead of time.

Answer 2

You are absolutely correct, here is what I came up with.

while True:

    for TmpSensor in W1ThermSensor.get_available_sensors():
        CurSensorID = TmpSensor.id
        CurTempC = round(float(TmpSensor.get_temperature()),1)
        CurTempF = round(float(TmpSensor.get_temperature(W1ThermSensor.DEGREES_F)),1)

        if CurSensorID == Fsensor:
            FtempC = CurTempC
            FtempF = CurTempF
#            print("F-Temp = " + str(FtempC) + " C" + ", " + str(FtempF) + " F")
        elif CurSensorID == Rsensor:
            RtempC = CurTempC
            RtempF = CurTempF
#            print("R-Temp = " + str(RtempC) + " C" + ", " + str(RtempF) + " F")
        elif CurSensorID == Isensor:
            ItempC = CurTempC
            ItempF = round(float(CurTempF))
#            print("I-Temp = " + str(ItempC) + " C" + ", " + str(ItempF) + " F")
        else:
            print("Unexpected Sensor = " + CurSensorID)





#----------------------------------------------------------------
#  Average and Convert Celsius to Fahrenheit
#----------------------------------------------------------------

    OtempC = round(float(OutsideTempAvg(FtempC, RtempC)))
    OtempF = round(float(OutsideTempAvg(FtempF, RtempF)))

#-----------------------------------------------------------------
#  Print for testing - Final will be sent to HMI display over Serial
#------------------------------------------------------------------     

    print("Outside Temperature = " + str(OtempF) + " Fahrenheit")
    print("Inside Temperature = " + str(ItempF) + " Fahrenheit")
#---------------------------------------------------------------------
#  Reset time - Final will be 5 minutes
#----------------------------------------------------------------------

    time.sleep(60.0)