RE: Newline (NuBe Question)

[AVI GROSS via Python-list]

Dave, I gave an example, again, and make no deep claims so your comments may be 
valid, without any argument.

I mentioned CSV and a related family such as TSV as they were a common and 
simple data format that has long been used. There are oodles of others and yes, 
these days many people can read directly from formats like some from EXCEL. But 
for data that can be shared to almost anyone using anything, something like 
Comma Separated Values is often used.

And some programs that generate such data simply keep appending a line at a 
time to a file and do not have any header line. There are even some programs 
that may not tolerate a file with a header line, or comments or other optional 
things, and some where header lines you can create would cause problems such as 
using an extended character set or escaped characters.

I have worked with these files in many languages and environments and my 
thought process here focused on recent work in R, albeit much applies 
everywhere. My point was really not about CSV but the convenience and 
advantages of data structures you can access by name when you want and 
sometimes also by position when you want. Too many errors can happen when 
humans doing programming are not able to concentrate. It is similar to 
arguments about file names. In the old UNIX days, and the same for other 
systems like VMS, a filename tended to have a format where relatively few 
characters were allowed and it might have two parts with the latter being an 
extension of up to 3 characters, or whatever. So file names like A321G12.dat 
were common and also next to it similar unpronounceable other file names. It 
was easy to confuse them and even people who worked with them regularly would 
forget what it might mean or use the wrong one. 

Well, if I load in a CSV in a language like R and there is no header line, as 
with some other data structures, it may make up a placeholder set of names like 
V1, V2 and so on. Yes, there are ways to specify the names as they are read in 
or afterward and they can be changed. But I have seen lots of CSV files offered 
with way too many columns and no names as well as documentation suggesting what 
names can be added if you wish.

This may be a bit off topic, but I want to add a bit in this context about 
additional concepts regarding name. As mentioned, there is a whole set of 
add-ons people sometimes use and in R, I like the tidyverse family and it 
allows some fairly sophisticated things to be done using names. There are ways 
to specify you want a subset of a data.frame (sometimes a version called a 
tibble) and you can ask for say all columns starting with "xyz" or containing 
it or ending with it. That can be very helpful if say we wave columns 
containing the height and weight and other metrics of say people in three 
clinics and your column names embed the name of the clinic, or other such 
examples, and you want to select one grouping for processing. You cannot easily 
do that without external info is it is just positional. 

An extension of this is how compactly you can do fairly complex things such as 
asking to create lots of new columns using calculations. You can specify, as 
above, which sets of columns to do this too and that you want the results for 
each XYY in XYZ.mean and XYZ.std and so on. You can skip oodles of carefully 
crafted and nested loops because of the ability to manipulate using column 
names at a high and often abstract level. 

And, just FYI, many other structures such as lists in R also support names for 
components. It can be very useful. But the overall paradigm compared to Python 
has major differences and I see strengths and weaknesses and tradeoffs.

Your dictionary example is one of them as numpy/pandas often make good use of 
them as part of dealing with similar data.frame type structures that are often 
simpler or easier to code with.

There is lots of AI discussion these days and some of what you say is 
applicable in that additional info besides names might be useful in the storage 
format to make processing it more useful. That is available in formats related 
to XML where fairly arbitrary markup can be made available.

Have to head out as this is already long enough.



-Original Message-
From: 'DL Neil'  
Sent: Monday, November 27, 2023 2:49 AM
To: avi.e.gr...@gmail.com; python-list@python.org
Subject: Re: Newline (NuBe Question)

Avi,

On 11/27/2023 4:15 PM, avi.e.gr...@gmail.com wrote:
> Dave,
> 
> Back on a hopefully more serious note, I want to make a bit of an analogy
> with what happens when you save data in a format like a .CSV file.
> 
> Often you have a choice of including a header line giving names to the
> resulting columns, or not.
> 
> If you read in the data to some structure, often to some variation I would
> loosely call a data.frame or perhaps something like a matrix, then without
> headers you have to specify what you want positionally or

Re: Newline (NuBe Question)

['DL Neil' via Python-list]

Avi,

On 11/27/2023 4:15 PM, avi.e.gr...@gmail.com wrote:

Dave,

Back on a hopefully more serious note, I want to make a bit of an analogy
with what happens when you save data in a format like a .CSV file.

Often you have a choice of including a header line giving names to the
resulting columns, or not.

If you read in the data to some structure, often to some variation I would
loosely call a data.frame or perhaps something like a matrix, then without
headers you have to specify what you want positionally or create your own
names for columns to use. If names are already there, your program can
manipulate things by using the names and if they are well chosen, with no
studs among them, the resulting code can be quite readable. More
importantly, if the data being read changes and includes additional columns
or in a different order, your original program may run fine as long as the
names of the columns you care about remain the same.

Positional programs can be positioned to fail in quite subtle ways if the
positions no longer apply.


Must admit to avoiding .csv files, if possible, and working directly 
with the .xls? original (cf expecting the user to export the .csv - and 
NOT change the worksheet thereafter).


However, have recently been using the .csv format (as described) as a 
placeholder or introduction to formatting data for an RDBMS.


In a tabular structure, the expectation is that every field (column/row 
intersection) will contain a value. In the RDBMS-world, if the value is 
not-known then it will be recorded as NULL (equivalent of Python's None).


Accordingly, two points:
1 the special case of missing/unavailable data can be handled with ease,
2 most 'connector' interfaces will give the choice of retrieving data 
into a tuple or a dictionary (where the keys are the column-names). The 
latter easing data-identification issues (as described) both in terms of 
improving over relational-positioning and name-continuity (or column 
changes/expansions).



The point about data 'appearing' without headings should be considered 
carefully. The phrase "create your own names for columns" only vaguely 
accesses the problem. If someone else has created/provided the data, 
then we need to know the exact design (schema = rules). What is the 
characteristic of each component? Not only column-names, but also what 
is the metric (eg the infamous confusion between feet and meters)...




As I see it, many situations where some aspects are variable are not ideal
for naming. A dictionary is an example that is useful when you have no idea
how many items with unknown keys may be present. You can iterate over the
names that are there, or use techniques that detect and deal with keys from
your list that are not present. Not using names/keys here might involve a
longer list with lots of empty slots to designate missing items, This
clearly is not great when the data present is sparse or when the number of
items is not known in advance or cannot be maintained in the right order.


Agreed, and this is the draw-back incurred by folk who wish to take 
advantage of the schema-less (possibility) NoSQL DBs. The DB enjoys 
flexibility, but the downstream-coder has to contort and flex to cope.


In this case, JSON files are an easy place-holder/intro for NoSQL DBs - 
in fact, Python dicts and MongoDB go hand-in-glove.



The next issue raised is sparseness. In a table, the assumption is that 
all fields, or at least most of them, will be filled with values. 
However, a sparse matrix would make such very 'expensive' in terms of 
storage-space (efficacy).


Accordingly, there are other ways of doing things. All of these involve 
labeling each data-item (thus, the data expressed as a table needs to be 
at least 50% empty to justify the structural change).


In this case, one might consider a tree-type of structure - and if we 
have to continue the pattern, we might look at a Network Database 
methodology (as distinct from a DB on a network!)




There are many other situations with assorted tradeoffs and to insist on
using lists/tuples exclusively would be silly but at the same time, if you
are using a list to hold the real and imaginary parts of a complex number,
or the X/Y[/Z] coordinates of a point where the order is almost universally
accepted, then maybe it is not worth using a data structure more complex or
derived as the use may be obvious.


No argument (in case anyone thought I might...)

See @Peter's earlier advice.

Much of the consideration (apart from mutable/immutable) is likely to be 
ease of coding. Getting down 'into the weeds' is probably pointless 
unless questions are being asked about (execution-time) performance...



Isn't the word "obvious" where this discussion started? Whereas "studs" 
might be an "obvious" abbreviation for "students" to some, it is not to 
others (quite aside from the abbreviation being unnecessary in this 
day-and-age).


Curiously, whereas I DO happen to think a point as ( x, y, ) or 

RE: Newline (NuBe Question)

[AVI GROSS via Python-list]

Dave,

Back on a hopefully more serious note, I want to make a bit of an analogy
with what happens when you save data in a format like a .CSV file.

Often you have a choice of including a header line giving names to the
resulting columns, or not.

If you read in the data to some structure, often to some variation I would
loosely call a data.frame or perhaps something like a matrix, then without
headers you have to specify what you want positionally or create your own
names for columns to use. If names are already there, your program can
manipulate things by using the names and if they are well chosen, with no
studs among them, the resulting code can be quite readable. More
importantly, if the data being read changes and includes additional columns
or in a different order, your original program may run fine as long as the
names of the columns you care about remain the same. 

Positional programs can be positioned to fail in quite subtle ways if the
positions no longer apply.

As I see it, many situations where some aspects are variable are not ideal
for naming. A dictionary is an example that is useful when you have no idea
how many items with unknown keys may be present. You can iterate over the
names that are there, or use techniques that detect and deal with keys from
your list that are not present. Not using names/keys here might involve a
longer list with lots of empty slots to designate missing items, This
clearly is not great when the data present is sparse or when the number of
items is not known in advance or cannot be maintained in the right order. 

There are many other situations with assorted tradeoffs and to insist on
using lists/tuples exclusively would be silly but at the same time, if you
are using a list to hold the real and imaginary parts of a complex number,
or the X/Y[/Z] coordinates of a point where the order is almost universally
accepted, then maybe it is not worth using a data structure more complex or
derived as the use may be obvious.

I do recall odd methods sometimes used way back when I programmed in C/C++
or similar languages when some method was used to declare small constants
like:

#define FIRSTNAME 1
#define LASTNAME 2

Or concepts like "const GPA = 3"

And so on, so code asking for student_record[LASTNAME] would be a tad more
readable and if the order of entries somehow were different, just redefine
the constant.

In some sense, some of the data structures we are discussing, under the
hood, actually may do something very similar as they remap the name to a
small integer offset. Others may do much more or be slower but often add
value in other ways. A full-blown class may not just encapsulate the names
of components of an object but verify the validity of the contents or do
logging or any number of other things. Using a list or tuple does nothing
else.

So if you need nothing else, they are often suitable and sometimes even
preferable. 


-Original Message-
From: Python-list  On
Behalf Of DL Neil via Python-list
Sent: Sunday, November 26, 2023 5:19 PM
To: python-list@python.org
Subject: Re: Newline (NuBe Question)

On 11/27/2023 10:04 AM, Peter J. Holzer via Python-list wrote:
> On 2023-11-25 08:32:24 -0600, Michael F. Stemper via Python-list wrote:
>> On 24/11/2023 21.45, avi.e.gr...@gmail.com wrote:
>>> Of course, for serious work, some might suggest avoiding constructs like
a
>>> list of lists and switch to using modules and data structures [...]
>>
>> Those who would recommend that approach do not appear to include Mr.
>> Rossum, who said:
>>Avoid overengineering data structures.
>^^^
> 
> The key point here is *over*engineering. Don't make things more
> complicated than they need to be. But also don't make them simpler than
> necessary.
> 
>>Tuples are better than objects (try namedtuple too though).
> 
> If Guido thought that tuples would always be better than objects, then
> Python wouldn't have objects. Why would he add such a complicated
> feature to the language if he thought it was useless?
> 
> The (unspoken?) context here is "if tuples are sufficient, then ..."


At recent PUG-meetings I've listened to a colleague asking questions and 
conducting research on Python data-structures*, eg lists-of-lists cf 
lists-of-tuples, etc, etc. The "etc, etc" goes on for some time! 
Respecting the effort, even as it becomes boringly-detailed, am 
encouraging him to publish his findings.

* sadly, he is resistant to OOP and included only a cursory look at 
custom-objects, and early in the process. His 'new thinking' has been to 
look at in-core databases and the speed-ups SQL (or other) might offer...

However, his motivation came from a particular application, and to 
create a naming-system so that he could distinguish a list-of-lists 
structure from some other tabular abstraction. The latter enables the 

Re: Newline (NuBe Question)

[Chris Angelico via Python-list]

On Mon, 27 Nov 2023 at 13:52, AVI GROSS via Python-list
 wrote:
>  Be that as it
> may, and I have no interest in this topic, in the future I may use the ever
> popular names of Primus, Secundus and Tertius and get blamed for using
> Latin.
>

Imperious Prima flashes forth her edict to "begin it". In gentler tone
Secunda hopes there will be nonsense in it. While Tertia interrupts
the tale not more than once a minute.

ChrisA
-- 
https://mail.python.org/mailman/listinfo/python-list

RE: Newline (NuBe Question)

[AVI GROSS via Python-list]

Isn't it fascinating that a meaningless piece of code used to illustrate
something can be analyzed as if it was full of malicious content?

Yes, my choice of names was as expected. The numbers chosen had no special
meaning other than choosing one number in each of three equivalence classes.

But, if you want me to add subtle meaning for generations to examine as it
it were a literary work, I offer this:

Peter and Paul were studs who got Mary'd.

Can we now go back to our regularly scheduled talking about aspects of a
computer language?

P.S.
And just for history, Paul was really Noel Paul Stookey but Peter, Paul &
Mary sounded more like new testament characters and I think Noel signifies a
birth to Peter and Mary, sort of, which might have fit too unless it was a
computer program where a name with an umlaut was once not common. Another
interpretation is that Noel came from the Latin word for news. Be that as it
may, and I have no interest in this topic, in the future I may use the ever
popular names of Primus, Secundus and Tertius and get blamed for using
Latin.

-Original Message-
From: Python-list  On
Behalf Of DL Neil via Python-list
Sent: Sunday, November 26, 2023 4:58 PM
To: python-list@python.org
Subject: Re: Newline (NuBe Question)

On 11/27/2023 12:48 AM, Chris Angelico via Python-list wrote:
> On Sun, 26 Nov 2023 at 21:08, Michael F. Stemper via Python-list
>  wrote:
>>
>> On 24/11/2023 21.45, avi.e.gr...@gmail.com wrote:
>>> Grizz[l]y,
>>>
>>> I think the point is not about a sorted list or sorting in general It is
>>> about reasons why maintaining a data structure such as a list in a
program
>>> can be useful beyond printing things once. There are many possible
examples
>>> such as having a list of lists containing a record where the third item
is a
>>> GPA for the student and writing a little list comprehension that selects
a
>>> smaller list containing only students who are Magna Cum Laude or Summa
Cum
>>> Laude.
>>>
>>> studs = [
>>> ["Peter", 82, 3.53],
>>> ["Paul", 77, 2.83],
>>> ["Mary", 103, 3.82]
>>> ]
>>
>> I've seen Mary, and she didn't look like a "stud" to me.
>>
> 
> That's what happens when you abbreviate "student" though :) Don't
> worry, there's far FAR worse around the place, and juvenile brains
> will always find things to snigger at, usually in mathematical
> libraries with "cumulative" functions.

The OP used an abbreviation: "studs". Why? Too lazy to type the full 
word? Abbreviation has full-meaning in the (narrow) domain? Was wanting 
something funny, or to snigger over?

Was the respondent sniggering? Perhaps he, like the OP, was also saving 
typing-time by making a joke, hoping that the OP would see the 
implicit-error in expecting others to understand that "studs" meant 
"students"?

Actually, Peter, Paul, and Mary were a band 
(https://www.peterpaulandmary.com/), so "studs" is even less expressive 
when the data also tells a story...

Working with "trainees", I avoid the word "student" even though some 
might see them as synonyms. In my mind, the abbreviation did not readily 
expand to the full word (mea culpa).

Accordingly, would not pass Code Review!
For the want of a few characters...
(https://en.wikipedia.org/wiki/For_Want_of_a_Nail)

--
Regards =dn
-- 
https://mail.python.org/mailman/listinfo/python-list

-- 
https://mail.python.org/mailman/listinfo/python-list

Re: Newline (NuBe Question)

[DL Neil via Python-list]

On 11/27/2023 10:04 AM, Peter J. Holzer via Python-list wrote:

On 2023-11-25 08:32:24 -0600, Michael F. Stemper via Python-list wrote:

On 24/11/2023 21.45, avi.e.gr...@gmail.com wrote:

Of course, for serious work, some might suggest avoiding constructs like a
list of lists and switch to using modules and data structures [...]


Those who would recommend that approach do not appear to include Mr.
Rossum, who said:
   Avoid overengineering data structures.

   ^^^

The key point here is *over*engineering. Don't make things more
complicated than they need to be. But also don't make them simpler than
necessary.


   Tuples are better than objects (try namedtuple too though).


If Guido thought that tuples would always be better than objects, then
Python wouldn't have objects. Why would he add such a complicated
feature to the language if he thought it was useless?

The (unspoken?) context here is "if tuples are sufficient, then ..."



At recent PUG-meetings I've listened to a colleague asking questions and 
conducting research on Python data-structures*, eg lists-of-lists cf 
lists-of-tuples, etc, etc. The "etc, etc" goes on for some time! 
Respecting the effort, even as it becomes boringly-detailed, am 
encouraging him to publish his findings.


* sadly, he is resistant to OOP and included only a cursory look at 
custom-objects, and early in the process. His 'new thinking' has been to 
look at in-core databases and the speed-ups SQL (or other) might offer...


However, his motivation came from a particular application, and to 
create a naming-system so that he could distinguish a list-of-lists 
structure from some other tabular abstraction. The latter enables the 
code to change data-format to speed the next process, without the coder 
losing-track of the data-type/format.


The trouble is, whereas the research reveals which is faster 
(in-isolation, and (only) on his 'platform'), my suspicion is that he 
loses all gains by reformatting the data between 'the most efficient' 
structure for each step. A problem of only looking at the 'micro', 
whilst ignoring wider/macro concerns.


Accordingly, as to the word "engineering" (above), a reminder that we 
work in two domains: code and data. The short 'toy examples' in training 
courses discourage us from a design-stage for the former - until we 
enter 'the real world' and meet a problem/solution too large to fit in a 
single human-brain. Sadly, too many of us are pre-disposed to be 
math/algorithmically-oriented, and thus data-design is rarely-considered 
(in the macro!). Yet, here we are...


--
Regards =dn
--
https://mail.python.org/mailman/listinfo/python-list

Re: Newline (NuBe Question)

[DL Neil via Python-list]

On 11/27/2023 1:08 AM, Roel Schroeven via Python-list wrote:
I prefer namedtuples or dataclasses over tuples. They allow you to refer 
to their fields by name instead of index: student.gpa is much clearer 
than student[2], and makes it less likely to accidentally refer to the 
wrong field.


+1
readability/comprehension!

--
Regards =dn
--
https://mail.python.org/mailman/listinfo/python-list

Re: RE: Newline (NuBe Question)

[Chris Angelico via Python-list]

On Mon, 27 Nov 2023 at 06:15,  wrote:
> But I learn from criticism. If I ever write a program like that and do not
> feel like typing, will this do?
>
> dents = [ ...]
>
> Or will that not include students who happen to be edentulous?
>

If they're learning to drive, this variable name would make complete sense.

ChrisA
-- 
https://mail.python.org/mailman/listinfo/python-list

Re: Newline (NuBe Question)

[DL Neil via Python-list]

On 11/27/2023 12:48 AM, Chris Angelico via Python-list wrote:

On Sun, 26 Nov 2023 at 21:08, Michael F. Stemper via Python-list
 wrote:


On 24/11/2023 21.45, avi.e.gr...@gmail.com wrote:

Grizz[l]y,

I think the point is not about a sorted list or sorting in general It is
about reasons why maintaining a data structure such as a list in a program
can be useful beyond printing things once. There are many possible examples
such as having a list of lists containing a record where the third item is a
GPA for the student and writing a little list comprehension that selects a
smaller list containing only students who are Magna Cum Laude or Summa Cum
Laude.

studs = [
["Peter", 82, 3.53],
["Paul", 77, 2.83],
["Mary", 103, 3.82]
]


I've seen Mary, and she didn't look like a "stud" to me.



That's what happens when you abbreviate "student" though :) Don't
worry, there's far FAR worse around the place, and juvenile brains
will always find things to snigger at, usually in mathematical
libraries with "cumulative" functions.


The OP used an abbreviation: "studs". Why? Too lazy to type the full 
word? Abbreviation has full-meaning in the (narrow) domain? Was wanting 
something funny, or to snigger over?


Was the respondent sniggering? Perhaps he, like the OP, was also saving 
typing-time by making a joke, hoping that the OP would see the 
implicit-error in expecting others to understand that "studs" meant 
"students"?


Actually, Peter, Paul, and Mary were a band 
(https://www.peterpaulandmary.com/), so "studs" is even less expressive 
when the data also tells a story...


Working with "trainees", I avoid the word "student" even though some 
might see them as synonyms. In my mind, the abbreviation did not readily 
expand to the full word (mea culpa).


Accordingly, would not pass Code Review!
For the want of a few characters...
(https://en.wikipedia.org/wiki/For_Want_of_a_Nail)

--
Regards =dn
--
https://mail.python.org/mailman/listinfo/python-list

Re: Newline (NuBe Question)

[Peter J. Holzer via Python-list]

On 2023-11-25 08:32:24 -0600, Michael F. Stemper via Python-list wrote:
> On 24/11/2023 21.45, avi.e.gr...@gmail.com wrote:
> > Of course, for serious work, some might suggest avoiding constructs like a
> > list of lists and switch to using modules and data structures [...]
> 
> Those who would recommend that approach do not appear to include Mr.
> Rossum, who said:
>   Avoid overengineering data structures.
  ^^^

The key point here is *over*engineering. Don't make things more
complicated than they need to be. But also don't make them simpler than
necessary.

>   Tuples are better than objects (try namedtuple too though).

If Guido thought that tuples would always be better than objects, then
Python wouldn't have objects. Why would he add such a complicated
feature to the language if he thought it was useless?

The (unspoken?) context here is "if tuples are sufficient, then ..."

hp

-- 
   _  | Peter J. Holzer| Story must make more sense than reality.
|_|_) ||
| |   | h...@hjp.at |-- Charles Stross, "Creative writing
__/   | http://www.hjp.at/ |   challenge!"


signature.asc
Description: PGP signature
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RE: RE: Newline (NuBe Question)

[AVI GROSS via Python-list]

Just FYI, I deliberately chose that abbreviation for a sort of irony as for
some people college is about almost anything except learning and some people
think they are studs and just  party and ...

And I am very tired of gender discussions. Lots of words now include two or
even more genders. Women are often now "actors", not actresses. I see no
reason women cannot be studs!

But I learn from criticism. If I ever write a program like that and do not
feel like typing, will this do?

dents = [ ...]

Or will that not include students who happen to be edentulous?


-Original Message-
From: Python-list  On
Behalf Of Chris Angelico via Python-list
Sent: Sunday, November 26, 2023 6:49 AM
To: python-list@python.org
Subject: Re: RE: Newline (NuBe Question)

On Sun, 26 Nov 2023 at 21:08, Michael F. Stemper via Python-list
 wrote:
>
> On 24/11/2023 21.45, avi.e.gr...@gmail.com wrote:
> > Grizz[l]y,
> >
> > I think the point is not about a sorted list or sorting in general It is
> > about reasons why maintaining a data structure such as a list in a
program
> > can be useful beyond printing things once. There are many possible
examples
> > such as having a list of lists containing a record where the third item
is a
> > GPA for the student and writing a little list comprehension that selects
a
> > smaller list containing only students who are Magna Cum Laude or Summa
Cum
> > Laude.
> >
> > studs = [
> >["Peter", 82, 3.53],
> >["Paul", 77, 2.83],
> >["Mary", 103, 3.82]
> > ]
>
> I've seen Mary, and she didn't look like a "stud" to me.
>

That's what happens when you abbreviate "student" though :) Don't
worry, there's far FAR worse around the place, and juvenile brains
will always find things to snigger at, usually in mathematical
libraries with "cumulative" functions.

ChrisA
-- 
https://mail.python.org/mailman/listinfo/python-list

-- 
https://mail.python.org/mailman/listinfo/python-list

RE: RE: Newline (NuBe Question)

[AVI GROSS via Python-list]

via Python-list
Sent: Saturday, November 25, 2023 9:32 AM
To: python-list@python.org
Subject: Re: RE: Newline (NuBe Question)

On 24/11/2023 21.45, avi.e.gr...@gmail.com wrote:
> Grizz[l]y,
> 
> I think the point is not about a sorted list or sorting in general It is
> about reasons why maintaining a data structure such as a list in a program
> can be useful beyond printing things once. There are many possible
examples
> such as having a list of lists containing a record where the third item is
a
> GPA for the student and writing a little list comprehension that selects a
> smaller list containing only students who are Magna Cum Laude or Summa Cum
> Laude.
> 
> studs = [
>["Peter", 82, 3.53],
>["Paul", 77, 2.83],
>["Mary", 103, 3.82]
> ]

I've seen Mary, and she didn't look like a "stud" to me.

> Of course, for serious work, some might suggest avoiding constructs like a
> list of lists and switch to using modules and data structures [...]

Those who would recommend that approach do not appear to include Mr.
Rossum, who said:
   
   Avoid overengineering data structures. Tuples are better than
   objects (try namedtuple too though). Prefer simple fields over
   getter/setter functions... Built-in datatypes are your friends.
   Use more numbers, strings, tuples, lists, sets, dicts. Also
   check out the collections library, eps. deque.[1]
   
I was nodding along with the people saying "list of lists" until I
reread this quote. A list of tuples seems most appropriate to me.

   
[1] <https://gist.github.com/hemanth/3715502>, as quoted by Bill
Lubanovic in _Introducing Python_

-- 
Michael F. Stemper
This sentence no verb.

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Re: Newline (NuBe Question)

[Roel Schroeven via Python-list]

Michael F. Stemper via Python-list schreef op 25/11/2023 om 15:32:

On 24/11/2023 21.45,avi.e.gr...@gmail.com  wrote:
> Grizz[l]y,
> 
> I think the point is not about a sorted list or sorting in general It is

> about reasons why maintaining a data structure such as a list in a program
> can be useful beyond printing things once. There are many possible examples
> such as having a list of lists containing a record where the third item is a
> GPA for the student and writing a little list comprehension that selects a
> smaller list containing only students who are Magna Cum Laude or Summa Cum
> Laude.
> 
> studs = [

>["Peter", 82, 3.53],
>["Paul", 77, 2.83],
>["Mary", 103, 3.82]
> ]

> Of course, for serious work, some might suggest avoiding constructs like a
> list of lists and switch to using modules and data structures [...]

Those who would recommend that approach do not appear to include Mr.
Rossum, who said:

Avoid overengineering data structures. Tuples are better than

objects (try namedtuple too though). Prefer simple fields over
getter/setter functions... Built-in datatypes are your friends.
Use more numbers, strings, tuples, lists, sets, dicts. Also
check out the collections library, eps. deque.[1]

I was nodding along with the people saying "list of lists" until I

reread this quote. A list of tuples seems most appropriate to me.


I prefer namedtuples or dataclasses over tuples. They allow you to refer 
to their fields by name instead of index: student.gpa is much clearer 
than student[2], and makes it less likely to accidentally refer to the 
wrong field.


--
"Man had always assumed that he was more intelligent than dolphins because
he had achieved so much — the wheel, New York, wars and so on — whilst all
the dolphins had ever done was muck about in the water having a good time.
But conversely, the dolphins had always believed that they were far more
intelligent than man — for precisely the same reasons."
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Re: RE: Newline (NuBe Question)

[Chris Angelico via Python-list]

On Sun, 26 Nov 2023 at 21:08, Michael F. Stemper via Python-list
 wrote:
>
> On 24/11/2023 21.45, avi.e.gr...@gmail.com wrote:
> > Grizz[l]y,
> >
> > I think the point is not about a sorted list or sorting in general It is
> > about reasons why maintaining a data structure such as a list in a program
> > can be useful beyond printing things once. There are many possible examples
> > such as having a list of lists containing a record where the third item is a
> > GPA for the student and writing a little list comprehension that selects a
> > smaller list containing only students who are Magna Cum Laude or Summa Cum
> > Laude.
> >
> > studs = [
> >["Peter", 82, 3.53],
> >["Paul", 77, 2.83],
> >["Mary", 103, 3.82]
> > ]
>
> I've seen Mary, and she didn't look like a "stud" to me.
>

That's what happens when you abbreviate "student" though :) Don't
worry, there's far FAR worse around the place, and juvenile brains
will always find things to snigger at, usually in mathematical
libraries with "cumulative" functions.

ChrisA
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Re: RE: Newline (NuBe Question)

[Michael F. Stemper via Python-list]

On 24/11/2023 21.45, avi.e.gr...@gmail.com wrote:

Grizz[l]y,

I think the point is not about a sorted list or sorting in general It is
about reasons why maintaining a data structure such as a list in a program
can be useful beyond printing things once. There are many possible examples
such as having a list of lists containing a record where the third item is a
GPA for the student and writing a little list comprehension that selects a
smaller list containing only students who are Magna Cum Laude or Summa Cum
Laude.

studs = [
   ["Peter", 82, 3.53],
   ["Paul", 77, 2.83],
   ["Mary", 103, 3.82]
]


I've seen Mary, and she didn't look like a "stud" to me.


Of course, for serious work, some might suggest avoiding constructs like a
list of lists and switch to using modules and data structures [...]


Those who would recommend that approach do not appear to include Mr.
Rossum, who said:
  
  Avoid overengineering data structures. Tuples are better than

  objects (try namedtuple too though). Prefer simple fields over
  getter/setter functions... Built-in datatypes are your friends.
  Use more numbers, strings, tuples, lists, sets, dicts. Also
  check out the collections library, eps. deque.[1]
  
I was nodding along with the people saying "list of lists" until I

reread this quote. A list of tuples seems most appropriate to me.

  
[1] , as quoted by Bill

Lubanovic in _Introducing Python_

--
Michael F. Stemper
This sentence no verb.

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RE: Newline (NuBe Question)

[AVI GROSS via Python-list]

Grizz[l]y,

I think the point is not about a sorted list or sorting in general It is
about reasons why maintaining a data structure such as a list in a program
can be useful beyond printing things once. There are many possible examples
such as having a list of lists containing a record where the third item is a
GPA for the student and writing a little list comprehension that selects a
smaller list containing only students who are Magna Cum Laude or Summa Cum
Laude. 

studs = [
  ["Peter", 82, 3.53],
  ["Paul", 77, 2.83],
  ["Mary", 103, 3.82] 
]
  
magna = [stud for stud in studs if stud[2] >= 3.5 ]
summa = [stud for stud in studs if stud[2] >= 3.75 ]

print(studs, magna, summa, sep="\n")

OUTPUT:

>>> print(studs, magna, summa, sep="\n")
[['Peter', 82, 3.53], ['Paul', 77, 2.83], ['Mary', 103, 3.82]]
[['Peter', 82, 3.53], ['Mary', 103, 3.82]]
[['Mary', 103, 3.82]]

Of course, for serious work, some might suggest avoiding constructs like a
list of lists and switch to using modules and data structures that are often
more efficient to represent your data such as some form of matrix or
data.frame.

And, yes, you can sort something like the above by name or GPA or number of
credits taken but the point was responding to why bother making a list just
to print it. The answer is that many and even most programs do a bit more
than that and a good choice of data structure facilitates ...




-Original Message-
From: Python-list  On
Behalf Of Grizzy Adams via Python-list
Sent: Thursday, November 16, 2023 8:41 AM
To: python-list@python.org
Subject: Re: Newline (NuBe Question)

Thursday, November 16, 2023  at 7:47, Thomas Passin via Python-list wrote:
Re: Newline (NuBe Question) (at least in part)

>I wrote that you don't need the "students" list, which is correct.  But 
>there could be a use for a list.  It would let you change the order in 
>which students appear in the printed output.  Knowing how to do that is 
>a useful skill.  But that should be left for a later lesson, not mixed 
>in here.

I have a vague memory of seeing sorted list somewhere ;->)
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Re: Newline (NuBe Question)

[Grizzy Adams via Python-list]

Thursday, November 16, 2023  at 7:47, Thomas Passin via Python-list wrote:
Re: Newline (NuBe Question) (at least in part)

>I wrote that you don't need the "students" list, which is correct.  But 
>there could be a use for a list.  It would let you change the order in 
>which students appear in the printed output.  Knowing how to do that is 
>a useful skill.  But that should be left for a later lesson, not mixed 
>in here.

I have a vague memory of seeing sorted list somewhere ;->)
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Re: Newline (NuBe Question)

[Thomas Passin via Python-list]

On 11/16/2023 1:19 AM, Grizzy Adams via Python-list wrote:

Wednesday, November 15, 2023  at 15:54, Thomas Passin via Python-list wrote:
Re: Newline (NuBe Question) (at least in part)


On 11/15/2023 2:04 PM, Grizzy Adams via Python-list wrote:

Wednesday, November 15, 2023  at 12:19, Pierre Fortin wrote:
Re: Newline (NuBe Question) (at least in part)
  

On Wed, 15 Nov 2023 16:51:09 - Grizzy Adams via Python-list wrote:



I don't give solutions; just a nudge...  you appear not to fully grok
"list"; your list is ONE list with no delineation between students. You
want a "list of lists"...
  

['Example High', 'Mary', 89.6, 'Pass', 'Example High', 'Matthew', 76.5, 'Fail', 
'Example High', 'Marie', 80.4, 'Fail', 'Example High', 'Manuel', 79.6, 'Fail', 
'Example High', 'Malala', 98.9, 'Pass']



Like this:
  

students = [
 ['Example High', 'Mary', 89.6, 'Pass'],
 ['Example High','Matthew', 76.5, 'Fail'],
 ['Example High', 'Marie', 80.4, 'Fail'],
 ['Example High', 'Manuel', 79.6, 'Fail'],
 ['Example High', 'Malala', 98.9, 'Pass']
]
  

for now I made a copt of code and altered to

students = []
grades = []



# In this design there is no point in the extra loop.
# also, the indentation is wrong.  Perhaps you inserted
# tabs?  Use only spaces in these posts.


I copy-pasted the code direct from IDLE, (to avoid any other typo's)


# Also you don't need the students list

for student in geographyClass:
# students.append(geographyStudent(s))

 s = geographyStudent(student)



  # for s in students:

   if s.finalGrade()>82: Result=("Pass")
   else: Result=("Fail")
   print(s.school, s.name, s.finalGrade(),Result)


I'll hive this a try (as a learning point)


I wrote that you don't need the "students" list, which is correct.  But 
there could be a use for a list.  It would let you change the order in 
which students appear in the printed output.  Knowing how to do that is 
a useful skill.  But that should be left for a later lesson, not mixed 
in here.


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Re: Newline (NuBe Question)

[Grizzy Adams via Python-list]

Wednesday, November 15, 2023  at 15:54, Thomas Passin via Python-list wrote:
Re: Newline (NuBe Question) (at least in part)

>On 11/15/2023 2:04 PM, Grizzy Adams via Python-list wrote:
>> Wednesday, November 15, 2023  at 12:19, Pierre Fortin wrote:
>> Re: Newline (NuBe Question) (at least in part)
 
>>> On Wed, 15 Nov 2023 16:51:09 - Grizzy Adams via Python-list wrote:

>>> I don't give solutions; just a nudge...  you appear not to fully grok
>>> "list"; your list is ONE list with no delineation between students. You
>>> want a "list of lists"...
 
>>>> ['Example High', 'Mary', 89.6, 'Pass', 'Example High', 'Matthew', 76.5, 
>>>> 'Fail', 'Example High', 'Marie', 80.4, 'Fail', 'Example High', 'Manuel', 
>>>> 79.6, 'Fail', 'Example High', 'Malala', 98.9, 'Pass']

>>> Like this:
 
>>> students = [
>>> ['Example High', 'Mary', 89.6, 'Pass'],
>>> ['Example High','Matthew', 76.5, 'Fail'],
>>> ['Example High', 'Marie', 80.4, 'Fail'],
>>> ['Example High', 'Manuel', 79.6, 'Fail'],
>>> ['Example High', 'Malala', 98.9, 'Pass']
>>> ]
 
>> for now I made a copt of code and altered to
>> 
>> students = []
>> grades = []

># In this design there is no point in the extra loop.
># also, the indentation is wrong.  Perhaps you inserted
># tabs?  Use only spaces in these posts.

I copy-pasted the code direct from IDLE, (to avoid any other typo's) 

># Also you don't need the students list
>> for student in geographyClass:
>>  # students.append(geographyStudent(s))
> s = geographyStudent(student)
>> 
>  # for s in students:
>>   if s.finalGrade()>82: Result=("Pass")
>>   else: Result=("Fail")
>>   print(s.school, s.name, s.finalGrade(),Result)

I'll hive this a try (as a learning point)

Thanks
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Re: Newline (NuBe Question)

[Thomas Passin via Python-list]

On 11/15/2023 2:04 PM, Grizzy Adams via Python-list wrote:

Wednesday, November 15, 2023  at 12:19, Pierre Fortin wrote:
Re: Newline (NuBe Question) (at least in part)


On Wed, 15 Nov 2023 16:51:09 - Grizzy Adams via Python-list wrote:

I don't give solutions; just a nudge...  you appear not to fully grok
"list"; your list is ONE list with no delineation between students. You
want a "list of lists"...



['Example High', 'Mary', 89.6, 'Pass', 'Example High', 'Matthew', 76.5, 'Fail', 
'Example High', 'Marie', 80.4, 'Fail', 'Example High', 'Manuel', 79.6, 'Fail', 
'Example High', 'Malala', 98.9, 'Pass']



Like this:



students = [
['Example High', 'Mary', 89.6, 'Pass'],
['Example High','Matthew', 76.5, 'Fail'],
['Example High', 'Marie', 80.4, 'Fail'],
['Example High', 'Manuel', 79.6, 'Fail'],
['Example High', 'Malala', 98.9, 'Pass']
]


for now I made a copt of code and altered to

students = []
grades = []


# In this design there is no point in the extra loop.
# also, the indentation is wrong.  Perhaps you inserted
# tabs?  Use only spaces in these posts.
# Also you don't need the students list

for student in geographyClass:
# students.append(geographyStudent(s))

s = geographyStudent(student)



 # for s in students:

  if s.finalGrade()>82: Result=("Pass")
  else: Result=("Fail")
  print(s.school, s.name, s.finalGrade(),Result)


This may help get you headed in the right direction:



for s in students:
print( s )



Hint: look forward to learning about f-strings...


I will look forward to them, may even go search ahead,


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Re: Newline (NuBe Question)

[Grizzy Adams via Python-list]

Wednesday, November 15, 2023  at 12:19, Pierre Fortin wrote:
Re: Newline (NuBe Question) (at least in part)

>On Wed, 15 Nov 2023 16:51:09 - Grizzy Adams via Python-list wrote:
>
>I don't give solutions; just a nudge...  you appear not to fully grok
>"list"; your list is ONE list with no delineation between students. You
>want a "list of lists"...

>>['Example High', 'Mary', 89.6, 'Pass', 'Example High', 'Matthew', 76.5, 
>>'Fail', 'Example High', 'Marie', 80.4, 'Fail', 'Example High', 'Manuel', 
>>79.6, 'Fail', 'Example High', 'Malala', 98.9, 'Pass']

>Like this:

>students = [
>['Example High', 'Mary', 89.6, 'Pass'],
>['Example High','Matthew', 76.5, 'Fail'],
>['Example High', 'Marie', 80.4, 'Fail'],
>['Example High', 'Manuel', 79.6, 'Fail'],
>['Example High', 'Malala', 98.9, 'Pass']
>]

for now I made a copt of code and altered to 

students = []
grades = []
for s in geographyClass:
students.append(geographyStudent(s))

for s in students:
 if s.finalGrade()>82: Result=("Pass")
   else: Result=("Fail")
   print(s.school, s.name, s.finalGrade(),Result)

>This may help get you headed in the right direction:

>for s in students:
>print( s )

>Hint: look forward to learning about f-strings...

I will look forward to them, may even go search ahead, 
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Re: Newline (NuBe Question)

[Pierre Fortin via Python-list]

On Wed, 15 Nov 2023 16:51:09 - Grizzy Adams via Python-list wrote:

I don't give solutions; just a nudge...  you appear not to fully grok
"list"; your list is ONE list with no delineation between students. You
want a "list of lists"...

>['Example High', 'Mary', 89.6, 'Pass', 'Example High', 'Matthew', 76.5, 
>'Fail', 'Example High', 'Marie', 80.4, 'Fail', 'Example High', 'Manuel', 79.6, 
>'Fail', 'Example High', 'Malala', 98.9, 'Pass']

Like this:

students = [
['Example High', 'Mary', 89.6, 'Pass'],
['Example High','Matthew', 76.5, 'Fail'],
['Example High', 'Marie', 80.4, 'Fail'],
['Example High', 'Manuel', 79.6, 'Fail'],
['Example High', 'Malala', 98.9, 'Pass']
]

This may help get you headed in the right direction:

for s in students:
print( s )

Hint: look forward to learning about f-strings...

HTH,
Pierre
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Re: Newline (NuBe Question)

[Grizzy Adams via Python-list]

Wednesday, November 15, 2023  at 9:45, Thomas Passin via Python-list wrote:
Re: Newline (NuBe Question) (at least in part)

>On 11/15/2023 2:25 AM, Grizzy Adams via Python-list wrote:
>> Hi & thanks for patience with what could be simple to you

>You may see responses that suggest various code alternatives.  But you 
>haven't shown us an example of what you want the output to look like,

Offered code got closer (sort of) my old code gave on long (only 5 records so 
far) list,

['Example High', 'Mary', 89.6, 'Pass', 'Example High', 'Matthew', 76.5, 'Fail', 
'Example High', 'Marie', 80.4, 'Fail', 'Example High', 'Manuel', 79.6, 'Fail', 
'Example High', 'Malala', 98.9, 'Pass']

offered code gave one tall column,

Example High
Mary
89.6
Pass
Example High
Matthew
76.5
Fail
Example High
Marie
80.4
Fail
Example High
Manuel
79.6
Fail
Example High
Malala
98.9
Pass

my ideal is one row for each student (I had edited manually to show this)

Example High, Mary, 89.6, Pass
Example High, Matthew, 76.5, Fail
Example High, Marie, 80.4, Fail
Example High, Manuel, 79.6, Fail
Example High, Malala, 98.9, Pass
 
>and you haven't said what else you plan to use the list for.  So anyone 
>who responds has to fly blind, without knowing key information.

I'll keep list for a while in case it gets used or reused later, for now it's 
just a test bed along with a few others, I can work thru as I learn 

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Re: Newline (NuBe Question)

[Thomas Passin via Python-list]

On 11/15/2023 2:25 AM, Grizzy Adams via Python-list wrote:

Hi & thanks for patience with what could be simple to you

Have this (from an online "classes" tutorial)

--- Start Code Snippit  ---

students = []
grades = []
for s in geographyClass:
students.append(geographyStudent(s))
for s in students:
 grades.append(s.school)
 grades.append(s.name)
 grades.append(s.finalGrade())
 if s.finalGrade()>82:
 grades.append("Pass")
 else:
 grades.append("Fail")
print(grades)

--- End Code Snippit  ---

I have extended (from tutorial) it a bit, I would really like to have a newline

at end of each record, I have searched (and tested) but cant get "\n" to give a

newline, I get "Mydata\n"

Do I need to replace "append" with "print", or is there a way to get the
newline in as I append to list?


First of all, if this is an accurate representation of the course 
material, you need a better course.  There's no sense in appending all 
those values one after another in a single list since later it will be 
very inconvenient to detect the end of one student's info and the start 
of the next one's.  And if you don't need to know that, but just want to 
print out the data, you don't need to a list at all, just print it out 
in the loop.


A list that contains lists of each student's data, one per interior 
list, would make more sense.


Second, it is usual to append data to a list without print formatting, 
and then add your formatting when you go to print the list.  That way 
you can use the list for other things beyond just printing, and the code 
is clearer and simpler as well.


You may see responses that suggest various code alternatives.  But you 
haven't shown us an example of what you want the output to look like, 
and you haven't said what else you plan to use the list for.  So anyone 
who responds has to fly blind, without knowing key information.


Asking for help is like writing code, with an added social element.  You 
have to be clear about the requirements, inputs, and desired outputs, 
and you have to organize your request in a way that's easy for others to 
understand and be willing to help.  Your original post is partway there 
already.


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Re: Newline (NuBe Question)

[Grizzy Adams via Python-list]

Wednesday, November 15, 2023  at 9:50, Alan Gauld via Python-list wrote:
Re: Newline (NuBe Question) (at least in part)

>On 15/11/2023 07:25, Grizzy Adams via Python-list wrote:

>> for s in students:
>> grades.append(s.school)
>> grades.append(s.name)
>> grades.append(s.finalGrade())
>> if s.finalGrade()>82:
>> grades.append("Pass")
>> else:
>> grades.append("Fail")
>> print(grades)
>> 
>> --- End Code Snippit  ---

>> Do I need to replace "append" with "print", or is there a way to get the 
>> newline in as I append to list?

>Firstly, it is usually a bad idea to mix formatting features(like
>newline) with the data. You will need to remove them again if you want
>to work with the data itself.

True, I onlt went that way when my (vain) attempts to add a newline any other 
way, my usual language is VB/VBA, Delphi or C++ at a push, so I'm really a nube 
here

>So, better to print the raw data and add the formatting during printing.

>There are a couple of options here (well more than a couple actually!)
>The simplest is to create another for loop and print each field with a
>newline automatically added by print()

>Another is to simply join everything in grades together separated by
>newlines. Python has a method to do that called join():

>print('\n'.join(grades))

>Unfortunately it seems your data has a mix of strings and numbers so
>that won't work without some tweaks:

>print('\n'.join(str(f) for f in grades))

that gets closer (sort of) my old code gave on long (only 5 records so far) 
list,

['Example High', 'Mary', 89.6, 'Pass', 'Example High', 'Matthew', 76.5, 'Fail', 
'Example High', 'Marie', 80.4, 'Fail', 'Example High', 'Manuel', 79.6, 'Fail', 
'Example High', 'Malala', 98.9, 'Pass']

your code gives one tall column, 

Example High
Mary
89.6
Pass
Example High
Matthew
76.5
Fail
Example High
Marie
80.4
Fail
Example High
Manuel
79.6
Fail
Example High
Malala
98.9
Pass

my ideal one row for each student (this I have edited manually)

Example High, Mary, 89.6, Pass
Example High, Matthew, 76.5, Fail
Example High, Marie, 80.4, Fail
Example High, Manuel, 79.6, Fail
Example High, Malala, 98.9, Pass

>However, I wonder if this really what you want? You have created grades as a
>long list containing all of the attributes of all of the students plus their
>Pass/Fail status. But you have no (easy)way to access the Pass/Fail value for
>each student. Do you really want to store the Pass/Fail in the student? And
>then print the students? Like so: 

I do want to keep the data in tact, incase it gets reused later in the 
tutorial(s)

>Just a thought...

>PS. There are neater ways to do this but you may not have covered
>those yet so I'll stick to basics.

I already jumped forward a bit (to python Classes)

Thanks
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Re: Newline (NuBe Question)

[Cameron Simpson via Python-list]

On 15Nov2023 07:25, Grizzy Adams  wrote:

Have this (from an online "classes" tutorial)


Response inline below.


students = []
grades = []
for s in geographyClass:
students.append(geographyStudent(s))
for s in students:
   grades.append(s.school)
   grades.append(s.name)
   grades.append(s.finalGrade())
   if s.finalGrade()>82:
   grades.append("Pass")
   else:
   grades.append("Fail")
print(grades)

--- End Code Snippit  ---

I have extended (from tutorial) it a bit, I would really like to have a newline
at end of each record, I have searched (and tested) but cant get "\n" 
to give a newline, I get "Mydata\n"


It would be useful to:
- see some of the things you've tried
- what their output actually was
- what output you actually want to achieve


Do I need to replace "append" with "print", or is there a way to get the
newline in as I append to list?


I think you're confusing output (print) with your data (the list of 
grades).


Is the code above genuinely what you're running?

I ask because it looks to me that you're:
- appending all the individual grade fields (school, name, ...) to one 
  long grades list containing all the data from all the students

- you're printing that single enormous list in one go at the end

What I'm imagine you want is one line of grade information per student.

Remember that indentation is important in Python. You're grades code 
looks like this:


grades = []
for s in students:
grades.append(s.school)
grades.append(s.name)
grades.append(s.finalGrade())
if s.finalGrade()>82:
grades.append("Pass")
else:
grades.append("Fail")
print(grades)

This:
- makes an empty list
- gathers up all of the student data
- prints the data in one go

I think you may want to do the first and last steps on a per student 
basis, not just once at the start and the end. So you might want to 
rearrange things:


for s in students:
grades = []
grades.append(s.school)
grades.append(s.name)
grades.append(s.finalGrade())
if s.finalGrade()>82:
grades.append("Pass")
else:
grades.append("Fail")
print(grades)

Cheers,
Cameron Simpson 
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Re: Newline (NuBe Question)

[Alan Gauld via Python-list]

On 15/11/2023 07:25, Grizzy Adams via Python-list wrote:

> for s in students:
> grades.append(s.school)
> grades.append(s.name)
> grades.append(s.finalGrade())
> if s.finalGrade()>82:
> grades.append("Pass")
> else:
> grades.append("Fail")
> print(grades)
> 
> --- End Code Snippit  ---

> Do I need to replace "append" with "print", or is there a way to get the 
> newline in as I append to list?

Firstly, it is usually a bad idea to mix formatting features(like
newline) with the data. You will need to remove them again if you want
to work with the data itself.

So, better to print the raw data and add the formatting during printing.

There are a couple of options here (well more than a couple actually!)
The simplest is to create another for loop and print each field with a
newline automatically added by print()

Another is to simply join everything in grades together separated by
newlines. Python has a method to do that called join():

print('\n'.join(grades))

Unfortunately it seems your data has a mix of strings and numbers so
that won't work without some tweaks:

print('\n'.join(str(f) for f in grades))


However, I wonder if this really what you want? You have created grades
as a long list containing all of the attributes of all of the students
plus their Pass/Fail status. But you have no (easy)way to access the
Pass/Fail value for each student. Do you really want to store the
Pass/Fail in the student? And then print the students? Like so:

for s in students
if s.finalGrade() > 82:
   s.result = "Pass"
else:
   s.result = "Fail"
print(s.school)
print(s.name)
...
print(s.result)

Just a thought...

PS. There are neater ways to do this but you may not have covered
those yet so I'll stick to basics.


-- 
Alan G
Author of the Learn to Program web site
http://www.alan-g.me.uk/
http://www.amazon.com/author/alan_gauld
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http://www.flickr.com/photos/alangauldphotos


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Re: Newline (NuBe Question)

[dn via Python-list]

On 15/11/2023 20.25, Grizzy Adams via Python-list wrote:

Hi & thanks for patience with what could be simple to you

Have this (from an online "classes" tutorial)


There are lots of on-line classes!



--- Start Code Snippit  ---

students = []
grades = []
for s in geographyClass:
students.append(geographyStudent(s))
for s in students:
 grades.append(s.school)
 grades.append(s.name)
 grades.append(s.finalGrade())
 if s.finalGrade()>82:
 grades.append("Pass")
 else:
 grades.append("Fail")
print(grades)

--- End Code Snippit  ---

I have extended (from tutorial) it a bit, I would really like to have a newline

at end of each record, I have searched (and tested) but cant get "\n" to give a

newline, I get "Mydata\n"

Do I need to replace "append" with "print", or is there a way to get the
newline in as I append to list?


Don't know how "Mydata..." results - where is it in the code.

What do you see when grades is printed?
Do you really want data-values all mashed together?

Yes, what changed after removal of all the .append()-s, and instead, 
within the (second) for-loop print( school, name, ... ) was used?


Is it easier to go on from there?

--
Regards,
=dn
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