On 12/12/2013 04:18, uga...@talktalk.net wrote:
I don't mind you asking if you don't understand something, but please
don't top post on this list, it makes following discussions such as this
more difficult than it need be.
--
My fellow Pythonistas, ask not what our language can do for you, as
Oops, I got this slightly wrong.
On 12/12/13 08:50, Alan Gauld wrote:
mult(3,0)
It returns zero because b is zero, right?
Now consider what it does for
mult(3,1)
It checks if b is zero, it's not, so it executes
rest = 3 + mult(3,0)
Sorry, it actually does:
rest = mult(3,0)
So rest equal
On 12/12/13 04:18, uga...@talktalk.net wrote:
In a way,it may help to identify the issue
def multiply(a,b)
return a*b
clearly returns the product of the two arguments, a and b
I presume it returns a+a rather than b+b+b
It depends on how multiplication is implemented in the CPU microcode.
But
multiply the arguments
How in the original def mult(a, b) . . .,
does mult(a, b-1) say return the product of a and b-1?
-Original Message-
From: Alan Gauld
To: tutor@python.org
Sent: Thu, 12 Dec 2013 0:27
Subject: Re: [Tutor] recursive function example
On 11/12/13 18:09, uga
On 11/12/13 18:09, uga...@talktalk.net wrote:
No, not really.
mutl(3, 2) has two arguments
rest = mult(a, b - 1) also has two arguments
rest does not have any arguments.
arguments are the values you pass *into* a function.
The function in turn passes back a return value.
In this case rest is
: Re: [Tutor] recursive function example
On 10/12/2013 14:48, uga...@talktalk.net wrote:
[snipped]
As you're clearly struggling here's my attempt at showing you what is
happening.
c:\Users\Mark\MyPython>type mytest.py
level = 0
def mult(a, b):
global level
This is a pretty good clarification! (debug prints well designed and well
placed)
Congrats, Mark!
denis
On 12/11/2013 06:37 PM, Mark Lawrence wrote:
On 10/12/2013 14:48, uga...@talktalk.net wrote:
[snipped]
As you're clearly struggling here's my attempt at showing you what is happening.
c:
On 12/11/2013 07:15 PM, Alan Gauld wrote:
Remember we are calling mul() several times, each with a new set of values.
So mul(3,2) calls mul(3,1)
and mul(3,1) calls mul(3,0)
mul(3.0) returns 0 to mul(3,1)
mul(3,1) then returns 3+0 => 3 to mul(3,2)
mul(3,2) returns 3+3 => 6.
This is a very cle
On 12/11/2013 03:56 PM, uga...@talktalk.net wrote:
Self-similar (fractal) recursion, sounds complex, I am guessing this is like
linear recursion but simultaneously in more than one dimension?
Curious business really. Wonders, if I may be a closet programmer, or something,
It is not complex,
On 11/12/13 12:36, uga...@talktalk.net wrote:
What I do not see is how?
Clearly, a = 3, it is constant throughout each iteration, and
if rest is equal to 3, then a + rest must be equal to 6.
Correct and the return value from the second invocation of mul() is 3.
You spoke of drilling down, a
On 10/12/2013 14:48, uga...@talktalk.net wrote:
[snipped]
As you're clearly struggling here's my attempt at showing you what is
happening.
c:\Users\Mark\MyPython>type mytest.py
level = 0
def mult(a, b):
global level
level += 1
print('level now', level, 'a =', a, 'b =', b)
if
ow the sub_res
outcomes are printed :)
-A
-Original Message-
From: spir
To: tutor@python.org
Sent: Wed, 11 Dec 2013 13:15
Subject: Re: [Tutor] recursive function example
On 12/10/2013 03:48 PM, uga...@talktalk.net wrote:
> [...]
Recursivity is hard to get really, meaning in
e.
I do not understand "+>", is it a typo perhaps?
Many thanks.
-A
-Original Message-
From: Alan Gauld
To: tutor@python.org
Sent: Wed, 11 Dec 2013 9:05
Subject: Re: [Tutor] recursive function example
On 10/12/13 14:48, uga...@talktalk.net wrote:
OK, I'll try a
On 12/11/2013 09:50 AM, Alan Gauld wrote:
Remember that each time mult() is called it creates
its own mini-world of variables independent of the
previous calls.
That, is a key point.
Denis
___
Tutor maillist - Tutor@python.org
To unsubscribe or cha
On 12/10/2013 03:48 PM, uga...@talktalk.net wrote:
[...]
Recursivity is hard to get really, meaning intuitively with your guts so-to-say.
Maybe using another example may help. Lets us say you want a function that sums
numbers from 1 up to n, the only input variable. (The result should thus be
On 10/12/13 14:48, uga...@talktalk.net wrote:
OK, I'll try again, this time just walking through the code from the top.
def mult(a, b):
if b == 0:
return 0
rest = mult(a, b - 1)
value = a + rest
return value
>
print "3 * 2 = ", mult(3, 2)
We print "3 * 2 = " and
-Original Message-
From: Alan Gauld
To: tutor@python.org
Sent: Wed, 11 Dec 2013 0:29
Subject: Re: [Tutor] recursive function example
On 10/12/13 14:48, uga...@talktalk.net wrote:
>> Here is original code:
>> def mult(a, b):
>> if b == 0:
&g
On 10/12/13 14:48, uga...@talktalk.net wrote:
Here is original code:
def mult(a, b):
if b == 0:
return 0
rest = mult(a, b - 1)
value = a + rest
return value
print "3 * 2 = ", mult(3, 2)
I see how python outputs the string "mult(3,2)" before running the
function,
N
18 matches
Mail list logo
