http://programming-crash-course.com
Regards, Clodoaldo Pinto
Very nicely laid out. Overall, a really nice presentation. 2 minor
points:
1) in the section on the interactive interpreter you have the sentence:
"In Linux open a shell and type python (must be lower case)". It
would be nice if the word 'python' were in a different font, or perhaps
in quotes, or something. You're targetting the "absolute beginner", so
you should assume the reader is not familiar with the CLI.
2) In the section on installing, you begin with:
"Python is an interpreted, interactive, object-oriented programming
language.". The complete novice sees those words and expects
them to be explained, but there is no definition given. I would
recommend simplifying that sentence, or explaining the terms.
> 1) in the section on the interactive interpreter you have the sentence:
> "In Linux open a shell and type python (must be lower case)". It
> would be nice if the word 'python' were in a different font, or perhaps
<code>python</code> would be good there.
> 2) In the section on installing, you begin with:
> "Python is an interpreted, interactive, object-oriented programming
> language.". The complete novice sees those words and expects
> them to be explained, but there is no definition given. I would
> recommend simplifying that sentence, or explaining the terms.
I had that same thought, actually.
Also, is the section called "pretty printing" mistitled? Doesn't that
name refer to the pprint module?
It looks real nice though.
Done, thanks.
>
> 2) In the section on installing, you begin with:
> "Python is an interpreted, interactive, object-oriented programming
> language.". The complete novice sees those words and expects
> them to be explained, but there is no definition given. I would
> recommend simplifying that sentence, or explaining the terms.
Ok, i will think about something, or just delete it.
Clodoaldo
If you have any suggestions for that page's title please do so.
Clodoaldo
My $0.02
It may not really be that misleading, especially if you've never heard
of pprint before. But you can always call it something simple like "The
'print' statement"
FWIW, being "interpreted" is not a feature of a language but of a given
implementation of a language - and actually, the reference
implementation (CPython) is byte-compiled, not interpreted. As for
interactivity, it comes from a program (the Python shell) that ships
with the reference implementation - not from the laguage itself.
This leaves us with "Python is an object-oriented programming language",
which is not 100% accurate since Python - even if strongly OO - also
supports the procedural and functional paradigms !-)
James
"Python is a remarkably powerful dynamic programming language that is
used in a wide variety of application domains. Python is often compared
to Tcl, Perl, Ruby, Scheme or Java. Some of its key distinguishing
features include:..."
Or the first page definition:
"Python® is a dynamic object-oriented programming language that can be
used for many kinds of software development. It offers strong support
for integration with other languages and tools, comes with extensive
standard libraries, and can be learned in a few days. Many Python
programmers report substantial productivity gains and feel the language
encourages the development of higher quality, more maintainable code."
I'm leaning towards the first page one from which i would take this
part out:
"is a dynamic object-oriented programming language"
That would leave this simple text:
"Python® can be used for many kinds of software development. It offers
strong support for integration with other languages and tools, comes
with extensive standard libraries, and can be learned in a few days.
Many Python programmers report substantial productivity gains and feel
the language encourages the development of higher quality, more
maintainable code."
Regards, Clodoaldo
I don't want him to now about types, at least not at that stage. I used
the term "integer" for the lack of a better one and I didn't mention
"float". Any suggestions?
Regards, Clodoaldo.
On 8 Apr 2006 09:02:22 -0700, Clodoaldo Pinto <clodoal...@gmail.com> wrote:
> I don't want him to now about types, at least not at that stage. I used
> the term "integer" for the lack of a better one and I didn't mention
> "float". Any suggestions?
>
> Regards, Clodoaldo.
>
> "Python is a remarkably powerful dynamic programming language that is
> used in a wide variety of application domains. Python is often compared
> to Tcl, Perl, Ruby, Scheme or Java. Some of its key distinguishing
> features include:..."
I'd be careful with that definition for newbies though. There's nothing
more frustrating (as a newbie myself) when Python (or anything else) is
compared to something as a way to explain it, yet I have no idea what
the other things are either! A programming newbie won't know about, and
maybe won't even have heard of, those other languages.
In general they are integers, and "integer" is not a Python type, so I
don't see a problem with the term. The problem I saw was that there was
no explanation for the returned value. Using the term "decimal" is
probably a bad idea, given Python decimals. But I'm not sure you need
to come up with a suitable term until you actually get round to
explaining types (at which point the problem disappears).
Duncan
Good point. I used the Python site front page definition without the
object oriented thing.
Regars, Clodoaldo
James
How would I explain that 3 / 2 is 1 without entering the type realm?
What if I say that if one don't use the point the interpreter will also
not use it? Would i be laying? Isn't it better to just let it go? I
think the typical non programmer newbie just don't care two much about
reasons as long as there is a clear rule. No point in the question then
no point in the answer.
> Using the term "decimal" is
> probably a bad idea, given Python decimals. But I'm not sure you need
> to come up with a suitable term until you actually get round to
> explaining types (at which point the problem disappears).
>
As I think float is scaring I changed it in the program comments where
it appeared for decimal. I don't worry about precision as much as I
worry about fluidity. I don't want anyone stoping to consult a
dictionary or a glossary.
Now the integer versus whole. As a non native english speaker I don't
know what sounds less mathematical and more natural. I changed integer
to whole following the previous suggestion but I really don't know.
Regards, Clodoaldo
Well you said something like "it returns an integer" without explaining
why the returned integer was 1 rather than, say, 10. So you probably
need to explain what integer division is, e.g.
http://mathworld.wolfram.com/IntegerDivision.html.
> What if I say that if one don't use the point the interpreter will also
> not use it? Would i be laying? Isn't it better to just let it go?
I reckon letting it go would lead to confusion. If I didn't know
already, I'd want to know why it returned 1. You can explain that
without referring to types, but just saying e.g. that ordinary division
is performed if the numerator or denominator is followed by a decimal point.
But as you use conversions to float in order to avoid integer division
in your code examples, it might be best to explain what's going on, even
if you do have to explain the relevant types.
I
> think the typical non programmer newbie just don't care two much about
> reasons as long as there is a clear rule. No point in the question then
> no point in the answer.
>
I can't imagine anyone (who doesn't already know) looking at the example
and not wondering why it returned 1 rather than something else.
>
>> Using the term "decimal" is
>>probably a bad idea, given Python decimals. But I'm not sure you need
>>to come up with a suitable term until you actually get round to
>>explaining types (at which point the problem disappears).
>>
>
>
> As I think float is scaring I changed it in the program comments where
> it appeared for decimal. I don't worry about precision as much as I
> worry about fluidity. I don't want anyone stoping to consult a
> dictionary or a glossary.
>
> Now the integer versus whole. As a non native english speaker I don't
> know what sounds less mathematical and more natural. I changed integer
> to whole following the previous suggestion but I really don't know.
>
Integer is more mathematical, and more precise. I just looked up some
definitions for "whole number", and found it can apparently mean
positive integer, non-negative integer, or integer. Maybe you can use
integer and just put "whole number" in brackets after it, the first time
you use it; as a vague definition? But describing the relevant types
and integer division might make your later examples clearer.
Duncan
Here is a idea. I am not sure if it is a good idea, but you can compare
it with the other suggestions for resolving this dilemma.
We know that Python is in the process of changing the division
operator. The main reason for the change is that the current approach
is not intuitive to a newcomer (whether experienced or not).
Why not think to the future, and do it like this. Instruct the reader
to enter 'from __future__ import division'. You do not have to explain
the details, just say that this is the way division will work in the
future, and this statement will eventually not be required.
Then your example will show that 3/2 = 1.5, which is what they would
expect.
Then you can mention that, if they just want the integer portion, they
can use int(3/2). I think that most people with the slightest
understanding of basic arithmetic will relate to this without a
problem.
My 2c
Frank Millman
I changed the comments in the first program that uses float() to:
# The raw_input() function asks the user for a text
# As a text can't be multiplied or divided the
# float() function tranforms the text into a decimal number
>
> I can't imagine anyone (who doesn't already know) looking at the example
> and not wondering why it returned 1 rather than something else.
>
...
>
> Integer is more mathematical, and more precise. I just looked up some
> definitions for "whole number", and found it can apparently mean
> positive integer, non-negative integer, or integer. Maybe you can use
> integer and just put "whole number" in brackets after it, the first time
> you use it; as a vague definition? But describing the relevant types
> and integer division might make your later examples clearer.
>
Now it says "integer (whole number)" followed by a link to a forum post
where this issue can be discussed.
http://programming-crash-course.com/integer_versus_float_division
Regards, Clodoaldo
Hmmm, maybe a picky point for a newbie, but since there actually is a
decimal module now, you might want to change the description of float().
> Why not think to the future, and do it like this. Instruct the reader
> to enter 'from __future__ import division'. You do not have to explain
> the details, just say that this is the way division will work in the
> future, and this statement will eventually not be required.
>
> Then your example will show that 3/2 = 1.5, which is what they would
> expect.
>
> Then you can mention that, if they just want the integer portion, they
> can use int(3/2). I think that most people with the slightest
> understanding of basic arithmetic will relate to this without a
> problem.
Or instead of converting the `float` back to an `int`, they can use
integer division: ``3 // 2``
Ciao,
Marc 'BlackJack' Rintsch
I had thought of that. The reason I did not suggest it is that, as I
understand it, this tutorial is not about how to learn Python, it is
about teaching programming to the absolute beginner.
I imagine (hope I am not making invalid assumptions here) that Python
was chosen as a base because it is easy and intuitive to learn, and in
most cases it is. It just happens that division is one area where it is
a bit awkward.
The // syntax is specific to Python. I don't think you are helping the
absolute beginner by forcing them to understand what is going on here.
On the other hand, int(x) is a basic mathematical concept (extract the
portion to the left of the decimal point) that is shared by several
languages and is fairly easy to understand.
My 2c (I am up to 4c now)
Frank
Right !!
>
> I imagine (hope I am not making invalid assumptions here) that Python
> was chosen as a base because it is easy and intuitive to learn, and in
> most cases it is. It just happens that division is one area where it is
> a bit awkward.
Right again !!
Although the Python way is almost always easy to learn I won't be
pythonic (as in specific to Python) where it won't help.
Regards, Clodoaldo