Newbie - Trying to Help a Friend

Alister alister.ware at ntlworld.com
Wed Nov 20 10:06:12 EST 2013


On Wed, 20 Nov 2013 14:49:59 +0000, Alister wrote:

> On Wed, 20 Nov 2013 13:57:30 +0000, Mark Lawrence wrote:
> 
>> On 20/11/2013 09:29, Alister wrote:
>>> On Wed, 20 Nov 2013 00:54:28 -0500, Dave Angel wrote:
>>>
>>>> On 20 Nov 2013 03:52:10 GMT, Steven D'Aprano <steve at pearwood.info>
>>>> wrote:
>>>>> 2 does count because it isn't divisible by 3. The question states,
>>>>> "[count] how many positive integers less than N are not divisible
>>>> by 2,3
>>>>> or 5". Two is not divisible by 3, so "not divisible by 2,3 or 5" is
>>>> true,
>>>>> so two gets counted.
>>>>
>>>>> The first number which is divisible by *all* of 2, 3 and 5 (i.e.
>>>> fails
>>>>> the test, and therefore doesn't get counted) is 30. The next few
>>>> that
>>>>> fail the test are 60, 90, 120, 150, 180, 210, 240, 270, 300, ...
>>>>> Remember, these are the numbers which should not be counted.
>>>>
>>>>>> I count 1, not 6
>>>>
>>>>> Out of curiosity, which number did you count?
>>>>
>>>> 1 of course. It's the only one that's not divisible by any of the
>>>> factors.
>>>>
>>>> Apparently we disagree about precedence and associativity in English.
>>>> I believe the not applies to the result of (divisible by 2, 3, or 5),
>>>> so I'd count 1, 7, 11, 13, 17, 19, 23. The first nonprime would be
>>>> 49.
>>>>
>>>> If I were trying to get the series you describe, I'd phrase it as
>>>>    "Not divisible by 2, and not divisible by 3, and not divisible by
>>>>    5"
>>>
>>> This ambiguity is a great example of why teachers (and enayone else
>>> responsible for specifying a programming project) should take greater
>>> care when specifying tasks.
>>> if it is to late to ask for clarification (the correct step in a real
>>> world case) I suggest you write 2 programs 1 for each interpretation,
>>> it will be good for your personal learning even if the teacher does
>>> not give any extra credit.
>>>
>>>
>> Ambiguity is the reason that some of the most expensive language
>> lessons in the world are at places like Sandhurst and West Point. 
>> Giving crystal clear orders, whether verbally or in writing, is
>> considered quite important in the military.
>> 
>> By the way, this is double posted and there were four identical
>> messages from you yesterday, finger trouble or what? :)
> 
> I don't think the problem is at my end. I am only sending once to the
> best of my knowledge (using Pan newsreader to Comp.lang.python)

Ok this is now silly
Apologies to everyone I am monitoring my network connection to confirm 
that i am not sending multiple times.
 



-- 
T-1's congested due to porn traffic to the news server.



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