Notes:
It is not good practice to put all your code for a block into one line like this. You can press Return after each instruction here and Python will show you “...” to indicate that it is expecting more instructions but remember to indent each line in the block with spaces.
Tip...
When you see ellipsis (…) it means that Python is expecting more instructions to follow your “while” instruction. Just press Return again to clear it.
>>> a = 0 >>> while (a < 10000): ... a+=1 ...
print ( "Raspberry Pi Users = " , a)
...
Running Python programs
Python programs don’t have to run from IDLE either. You could use any application to create the text and then run the program using Python directly. You could even use a word processor but you’ll find that it keeps trying to capitalise words at the start of each line and correct your grammar. It is not recommended you try to use a word processor for programming! Those programs you created before can be edited using the “nano” text editor, for example. Open up the Linux terminal so you can see a “$” prompt. Open the program you created earlier – factors.py – in the nano editor, using:
$ nano factors.py
With some trial and error, you should be able to use nano to change the program to read:
for number in range (1, 51): factors = 0 print (number, end= ": " )
for divisor in range (1, number+1): if number%divisor == 0: print (divisor, end= " " )
factors+=1 if (factors == 2):
print ( "and is a prime number" )
else :
print ()
Save it (“Ctrl-O”), close nano (“Ctrl-X”) and then, to run in the terminal window, type this:
$ python factors.py
You should see the program’s output in the Linux terminal window, as it did in the IDLE Python Shell.
For the remainder of this Python section, we will use IDLE but, if you prefer, you can use a different text editor and run your programs from the Linux terminal as shown here.
Experiments in Python
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