Re: [Tutor] Newbie question re. Functions
Thats fine, but what differance does it make?I can see no way that it improves the code.I assume later on when the function is called, it should look as follows:move = ask_number("Where will you move? (0-8): ", 0, NUM_SQUARES, 1)
JonOn 01/02/06, Ed Singleton <[EMAIL PROTECTED]> wrote:
On 31/01/06, Jon Moore <[EMAIL PROTECTED]> wrote:> Improve the function ask_number() so that the function can be called with a> step value. Make the default value of step 1.
>> The function looks like this:>> def ask_number(question, low, high):> """Ask for a number within the range"""> response = None> while response not in range(low, high):
> response = int(raw_input(question))> return responseTo be honest, this made sense to me. I assumed the author wants youto be able to do the following:ask_number("Give me an even number between 1 and 10", 1, 10, 2)
The solution would be:def ask_number(question, low, high, step=1):"""Ask for a number within the range"""response = Nonewhile response not in range(low, high, step):
response = int(raw_input(question))return responseBut I definitely agree that he said it very, very badly.Ed___Tutor maillist -
Tutor@python.orghttp://mail.python.org/mailman/listinfo/tutor-- Best Regards
Jon Moore
___
Tutor maillist - Tutor@python.org
http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
On 31/01/06, Jon Moore <[EMAIL PROTECTED]> wrote:
> Improve the function ask_number() so that the function can be called with a
> step value. Make the default value of step 1.
>
> The function looks like this:
>
> def ask_number(question, low, high):
> """Ask for a number within the range"""
> response = None
> while response not in range(low, high):
> response = int(raw_input(question))
> return response
To be honest, this made sense to me. I assumed the author wants you
to be able to do the following:
ask_number("Give me an even number between 1 and 10", 1, 10, 2)
The solution would be:
def ask_number(question, low, high, step=1):
"""Ask for a number within the range"""
response = None
while response not in range(low, high, step):
response = int(raw_input(question))
return response
But I definitely agree that he said it very, very badly.
Ed
___
Tutor maillist - Tutor@python.org
http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
> Are you the author of Learn to Program Using Python: A Tutorial for > Hobbyists, Self-starters and All Who Want to Learn the Art of Computer > Programming? Yes. > Is the book still available as a web site? Yes. It has been substantially rewritten sionce the book was done to cover more recent features of Python. But the basic structure and content is still the same. The book has 3 chapters whose copyright belongs to Addison Wesley and thus are not on the web site but OTOH the web site has several topics which were written after the book was published Alan G Author of the learn to program web tutor http://www.freenetpages.co.uk/hp/alan.gauld ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
AlanAre you the author of Learn to Program Using Python: A Tutorial for Hobbyists, Self-starters and All Who Want to Learn the Art of Computer Programming? Is the book still available as a web site?JonOn 31/01/06, Alan Gauld <[EMAIL PROTECTED] > wrote:> So a general recommendation to authors is to have a member of the target > audience "test" the book. You Jon have done that but at some cost to you> and those of us on this list.One advantage of doing my book as a web site first was that I had plentyof testers before committing to print (over 100k visitors). Mind you the paperversion still had plenty of mistakes but mostly those were typos...Alan G.-- Best RegardsJon Moore ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
DannyMany thanks for that, I notice a few erratas that I am yet to come up against. This will save my sanity (well some of it)1JonOn 31/01/06, Danny Yoo <[EMAIL PROTECTED]> wrote: On Tue, 31 Jan 2006, Jon Moore wrote:> I have been looking for contact details for the author to ask him what> he was eluding to with the exercise, but to no avail.Hi Jon,I did find errata here: http://www.muskalipman.com/ptr_detail.cfm?group=Programming&all=1&isbn=1-59200-073-8(bottom of the page) but as far as contact information, I haven't been able to find anything.I do agree the challenege exercise as you've put it seems somewhatnonsensical. *grin* -- Best RegardsJon Moore ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
> So a general recommendation to authors is to have a member of the target > audience "test" the book. You Jon have done that but at some cost to you > and those of us on this list. One advantage of doing my book as a web site first was that I had plenty of testers before committing to print (over 100k visitors). Mind you the paper version still had plenty of mistakes but mostly those were typos... Alan G. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
On Tue, 31 Jan 2006, Jon Moore wrote: > I have been looking for contact details for the author to ask him what > he was eluding to with the exercise, but to no avail. Hi Jon, I did find errata here: http://www.muskalipman.com/ptr_detail.cfm?group=Programming&all=1&isbn=1-59200-073-8 (bottom of the page) but as far as contact information, I haven't been able to find anything. I do agree the challenege exercise as you've put it seems somewhat nonsensical. *grin* ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
I know. Its hard enough for someone like me as it is without things like this complicating it!I have another one for the group, but I will save it for another day ;)I have been looking for contact details for the author to ask him what he was eluding to with the exercise, but to no avail. JonOn 31/01/06, Bob Gailer <[EMAIL PROTECTED]> wrote: Jon Moore wrote:> Hi,>> I am still working my way through my 'Python for absolute beginners> book' and have hit a brick wall with one of the end of chapter exercises.>> The challenge says: >> Improve the function ask_number() so that the function can be called> with a step value. Make the default value of step 1.>> The function looks like this:>> def ask_number(question, low, high): > """Ask for a number within the range"""> response = None> while response not in range(low, high):> response = int(raw_input(question))> return response >> The author has not eluded to 'step values' in anyway that I can see in> the proceeding chapters!This lights my frustration fire. I wonder whether the author tested thebook?When I worked for a training company I was asked to test a new on-line course on JCL. I demurred by saying "But I don't know JCL.". The replywas "that's exactly what we want!"So a general recommendation to authors is to have a member of the targetaudience "test" the book. You Jon have done that but at some cost to you and those of us on this list.-- Best RegardsJon Moore ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
Jon Moore wrote: > Hi, > > I am still working my way through my 'Python for absolute beginners > book' and have hit a brick wall with one of the end of chapter exercises. > > The challenge says: > > Improve the function ask_number() so that the function can be called > with a step value. Make the default value of step 1. > > The function looks like this: > > def ask_number(question, low, high): > """Ask for a number within the range""" > response = None > while response not in range(low, high): > response = int(raw_input(question)) > return response > > The author has not eluded to 'step values' in anyway that I can see in > the proceeding chapters! This lights my frustration fire. I wonder whether the author tested the book? When I worked for a training company I was asked to test a new on-line course on JCL. I demurred by saying "But I don't know JCL.". The reply was "that's exactly what we want!" So a general recommendation to authors is to have a member of the target audience "test" the book. You Jon have done that but at some cost to you and those of us on this list. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
I guess I am not going mad then!I will skip this exercise and move on.ThanksJonOn 31/01/06, Alan Gauld < [EMAIL PROTECTED]> wrote:Hi Jon,> Improve the function ask_number() so that the function can be called with > a> step value. Make the default value of step 1.If its any consolation that doesn't really mean much to me either.I understand the concept of step value - range() takes one forexample, check the docs. But how a step value would be used in this kind of user-input scenarioI have no idea!def ask_number(question, low, high):"""Ask for a number within the range""" response = Nonewhile response not in range(low, high):response = int(raw_input(question))return responseThe only possibility I can think of is that the step value is used tonarrow the acceptable range each time round the loop. But given we don't necessarily tell the user what the range is that would beweird. We'd need to modify question as we go or something.On the assumption you aren't being marked on this I'd justmake up your own mind what it should do and do it! :-) ...and treat it as a good example of a bad statement ofrequirements!Alan G-- Best RegardsJon Moore ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
Hi Jon, > Improve the function ask_number() so that the function can be called with > a > step value. Make the default value of step 1. If its any consolation that doesn't really mean much to me either. I understand the concept of step value - range() takes one for example, check the docs. But how a step value would be used in this kind of user-input scenario I have no idea! def ask_number(question, low, high): """Ask for a number within the range""" response = None while response not in range(low, high): response = int(raw_input(question)) return response The only possibility I can think of is that the step value is used to narrow the acceptable range each time round the loop. But given we don't necessarily tell the user what the range is that would be weird. We'd need to modify question as we go or something. On the assumption you aren't being marked on this I'd just make up your own mind what it should do and do it! :-) ...and treat it as a good example of a bad statement of requirements! Alan G ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Newbie question re. Functions
Jon Moore wrote: > Hi, > > I am still working my way through my 'Python for absolute beginners > book' and have hit a brick wall with one of the end of chapter exercises. > > The challenge says: > > Improve the function ask_number() so that the function can be called > with a step value. Make the default value of step 1. > > The function looks like this: > > def ask_number(question, low, high): > """Ask for a number within the range""" > response = None > while response not in range(low, high): > response = int(raw_input(question)) > return response > > The author has not eluded to 'step values' in anyway that I can see in > the proceeding chapters! I have the book and I don't understand what he is asking for in that question either. To me a 'step value' would be something that alters a sequence, for example the third argument to range() is a step value: >>> help(range) Help on built-in function range in module __builtin__: range(...) range([start,] stop[, step]) -> list of integers Return a list containing an arithmetic progression of integers. range(i, j) returns [i, i+1, i+2, ..., j-1]; start (!) defaults to 0. When step is given, it specifies the increment (or decrement). For example, range(4) returns [0, 1, 2, 3]. The end point is omitted! These are exactly the valid indices for a list of 4 elements. >>> range(0, 6) [0, 1, 2, 3, 4, 5] >>> range(0, 6, 2) [0, 2, 4] Kent ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
