Python while 循环语法无效
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Python while loop with invalid syntax
提问by cmbrooks
Just to give some background on the project I am working on before I show the code. I am currently developing a Python script that will be running on a Raspberry Pi to monitor the float switch from a sump pump in my basement. This code will check to see if the sump pump is not working by these two criteria:
在我展示代码之前，只是提供一些我正在处理的项目的背景知识。我目前正在开发一个 Python 脚本，该脚本将在 Raspberry Pi 上运行，以监控我地下室污水泵的浮子开关。此代码将检查污水泵是否不符合以下两个标准：
- If the switch is on for more than three minutes
- If the switch turns on and off more than 10 times in three minutes
- 如果开关打开超过三分钟
- 如果开关在三分钟内打开和关闭超过 10 次
I am not done with the rest of the code, but here is what I have:
我还没有完成其余的代码，但这是我所拥有的：
import time
import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(17, GPIO.IN)
floatSwitch = GPIO.input(17)
import smtplib
running = True
log = open("sumpPumpLog.txt", "r+")
startTime = time.time()
def elapsedTime():
"""This function checks how much time
has elapsed since the timer has started"""
endtime = time.time()
elapsed = endtime - starttime
return elapsed
def sendEmail(*msg):
"""This function sends an email to selected recipients with a custom
message as well as the log file attached."""
#enter the code that sends an email to the family with the log attached
fromaddr = '[email protected]'
toaddrs = [[email protected]']
msg = """Please see the Pi and the data log file for more details."""
# Credentials (if needed)
username = 'my_username'
password = 'my_password'
msg.attached()
# The actual mail send
server = smtplib.SMTP('smtp.gmail.com:587')
server.starttls()
server.login(username, password)
server.sendmail(fromaddr, toaddrs, msg)
server.quit()
if running is True:
if floatSwitch is True:
#Write the time and what happened to the file
log.write(str(time.time() + "Float switch turned on")
#Wait until switch is turned off
while floatSwitch is True:
startTime = time.time()
if floatSwitch is False:
log.write(str(now) + "Float switch turned off")
break
#if elapsedTime > 3 min (in the form of 180 seconds)
elif elapsedTime() > 180:
log.write(str(now) + "Sump Pump has been deemed broaken")
sendEmail("The sump pump is now broken.")
else:
log.write(str(time.time() + "The sctipt has stopped.")
sendEmail("The script has been stopped.")
My problem is that on line 52 when it says
我的问题是在第 52 行，当它说
while floatSwitch is True:
There is an error in the code, and all it says is 'invalid syntax' I am very new to Python, and this is my first real project with it. I am unfamiliar with a lot of the syntax, so this could be a very elementary mistake. Can anyone please help me fix the syntax of this statement so that I can get my code to work. I know that there are numerous other mistakes without the rest of the code, but I am planning to work out those bugs when I find them. I have searched around, but I cannot find another example like this. Any and all help is very appreciated!
代码中有一个错误，它说的是“无效语法”我对 Python 非常陌生，这是我第一个真正使用它的项目。我不熟悉很多语法，所以这可能是一个非常基本的错误。任何人都可以帮我修复此语句的语法，以便我的代码可以正常工作。我知道在没有其余代码的情况下还有许多其他错误，但是我计划在找到这些错误时解决它们。我四处搜索，但找不到这样的另一个例子。非常感谢任何和所有帮助！
采纳答案by Rohit Jain
Actually, your problem is with the line abovethe while-loop. You are missing a parenthesis:
实际上，您的问题出在 while 循环上方的那一行。您缺少一个括号：
log.write(str(time.time() + "Float switch turned on"))
here--^
Also, just a tip for the future, instead of doing this:
另外，只是对未来的一个提示，而不是这样做：
while floatSwitch is True:
it is cleaner to just do this:
这样做更干净：
while floatSwitch:
回答by Rohit Jain
You have an unbalanced parenthesis on your previous line:
您在上一行中有一个不平衡的括号：
log.write(str(time.time() + "Float switch turned on")) # Last parenthesis is missing
And also in sendEmail()method, you have a missing opening quote:
而且在sendEmail()方法中，您缺少开头引用：
toaddrs = [[email protected]'] # Opening quote missing
