How to do while loops with multiple conditions

user_228653 0
Viewed 210303

I have a while loop in python

condition1=False
condition1=False
val = -1

while condition1==False and condition2==False and val==-1:
    val,something1,something2 = getstuff()

    if something1==10:
        condition1 = True

    if something2==20:
        condition2 = True

'
'

I want to break out of the loop when all these conditions are true, the code above does not work

I originally had 

while True:
      if condition1==True and condition2==True and val!=-1:
         break

which works ok, is this the best way to do this?

Thanks

logic python
6 Answers

Change the ands to ors.

Ignacio_Vazquez-Abrams_208620 
while not condition1 or not condition2 or val == -1:

But there was nothing wrong with your original of using an if inside of a while True.

Admin1

Have you noticed that in the code you posted, condition2 is never set to False? This way, your loop body is never executed.

Also, note that in Python, not condition is preferred to condition == False; likewise, condition is preferred to condition == True.

user_68990

I am not sure it would read better but you could do the following:

while any((not condition1, not condition2, val == -1)):
    val,something1,something2 = getstuff()

    if something1==10:
        condition1 = True

    if something2==20:
        condition2 = True
user_29790

use an infinity loop like what you have originally done. Its cleanest and you can incorporate many conditions as you wish

while 1:
  if condition1 and condition2:
      break
  ...
  ...
  if condition3: break
  ...
  ...
user_1315270
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