Multiple lines? - Printable Version

Multiple lines? - Printable Version

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+--- Thread: Multiple lines? (/thread-6297.html)

Multiple lines? - Noobie12 - Nov-14-2017

Hello, everyone. I'm fairly new to coding and in a bit of a jam. I'm trying to type out this example i saw online on IDLE and it reads something like this.

1 response = input("What is your radius? ")
2 r = float(response)
3 area = 3.14159 * r ** 2
4 print("The area is ", area)

But MY code stops at the 2nd line.

>>> response = input("What is your radius?")
What is your radius?

What am I doing wrong or how do i get my code to look something like the example? And how come I can't code offline? Any help is greatly appreciated.

RE: Multiple lines? - Larz60+ - Nov-15-2017

the code will break on line 2
if response contains anything other than a number,
including an empty line.
you can use:

while True:
    response = input("What is your radius? ")
    if response.isdigit():
        break
    print('Please enter a number')

RE: Multiple lines? - Noobie12 - Nov-15-2017

(Nov-15-2017, 12:49 AM)Larz60+ Wrote: the code will break on line 2
if response contains anything other than a number,
including an empty line.
you can use:
while True:
    response = input("What is your radius? ")
    if response.isdigit():
        break
    print('Please enter a number')

How did you get it to go to the next line without executing the first line? the first code i posted is supposed to work but i cant go to the next line. I'm not sure if im making any sense. What are you using to code? If you copy and paste the first code

response = input("What is your radius? ")
r = float(response)
area = 3.14159 * r ** 2
print("The area is ", area)

and press enter. It works fine. I just cant get to the next line in IDLE. If i type

>>> response = ("What is your radius? ")
>>> r = float(response)
Traceback (most recent call last):
  File "<pyshell#1>", line 1, in <module>
    r = float(response)
ValueError: could not convert string to float: 'What is your radius? '
>>>

I get that error. I'm not sure what im doing wrong and why the first code from the example online works and i cant type it out on IDLE like the example.

RE: Multiple lines? - Larz60+ - Nov-15-2017

Quote:and press enter. It works fine. I just cant get to the next line in IDLE. If i type

Not if you input text, it will still crash
the way I wrote it:

while True:

this starts an endless loop. It says execute all following indented code, forever.
the input statement is the same:

    response = input("What is your radius? ")

nothing special here.

the next line:

    if response.isdigit():
        break

says 'If the value i response is numeric, I've got what I want, so break the endless loop'
and does just that.

If it is not numeric, it continues on to the next line, printing the message

    print('Please enter a number')

And restarts the loop

RE: Multiple lines? - buran - Nov-15-2017

Compare

response = input("What is your radius? ")

with

response = ("What is your radius? ")

do you see the difference?