What Can Be Used Instead of "while" In Python, NO Loops?

[gurgy11]

Is there something in Python that allows me to do something, like "while" but without looping?

Can I use variables from inside of "while" in this "alternative"?

Thank you!

[joan]

Basically a while loop is

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while condition:
   statements

If you don't want to loop it just becomes

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statements

What are you trying to achieve?

[gurgy11]

Basically a while loop is

Code: Select all

while condition:
   statements

If you don't want to loop it just becomes

Code: Select all

statements

What are you trying to achieve?

I'm trying to send an email everytime an LED lights up.

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import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
GPIO_PIR = 7 # Pin 26
GPIO_LED = 4 # Pin 7
GPIO.setup(GPIO_LED,GPIO.OUT)
GPIO.setup(GPIO_PIR,GPIO.IN)

print " Press Ctrl & C to Quit"

try:
    while GPIO.input(GPIO_PIR)==1:
        Motion = 0
    print " Ready"

    Motion = 0

    while True:
        if GPIO.input(GPIO_PIR)==1:
            if Motion == 0:
                print " Motion detected!"
                Motion = 1
            GPIO.output(GPIO_LED, True)
        else:
            if Motion == 1:
                print " Clear "
                Motion = 0
            GPIO.output(GPIO_LED, False)
            import smtplib

            content = 'example stuff'
            mail = smtplib.SMTP('smtp.gmail.com',587)
            mail.ehlo()
            mail.starttls()
            mail.login('EMAIL','PASSWORD')
            mail.sendmail('EMAIL','RECEIVER_EMAIL',content)
            mail.close()
            
except KeyboardInterrupt:
    print " Quit"
    GPIO.cleanup()

Notice where I try to send an email? It just loops, and sends me TONS of email! Haha!

Any example on how I can get it to send me only ONE email only once the LED Lights up, and not loop continuously?

Thanks!

[kusti8]

All you need to do is put another while in the while loop which waits until the led turns off, and then continues.

[gurgy11]

All you need to do is put another while in the while loop which waits until the led turns off, and then continues.

Okay, I'll try that. My original understanding was that "while" loops.

[gurgy11]

All you need to do is put another while in the while loop which waits until the led turns off, and then continues.

Sorry, but could you show me exactly where to put it?

(I'm completely new to this sort of stuff )

[ame]

You could store the previous state of the LED, and only send an email if the state changes to 'on'.

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last_state=false

while true:
    new_state=GPIO input

    if new_state and not last_state:
        send email

    last_state=new_state