Experiences/guidance on teaching Python as a first programminglanguage

[Oscar Benjamin]

Hi all,

I work in a University Engineering faculty teaching, among other
things, programming. In our last meeting about improving our teaching
syllabus and delivery we've identified the first year programming
courses as an area where there is room for improvement and we're
considering (mainly on my suggestion) switching to using Python as the
first programming language that we use to introduce our students to
programming. I'm interested to know if anyone can share experience of
a similar situation or can point to any case studies about this.

The course is for ~100 1st year students with half studying
Engineering Mathematics and the other half Electrical Engineering.
Currently we introduce programming with C for the 1st semester and
then C++ for the 2nd semester. In the 3rd semester they learn Matlab
and following on from that they can take optional units run by the CS
department in Java, Haskell and many more. Our faculty does not
currently offer any Python courses for students at any level in CS or
Engineering.

Many of the students complain that the C course is too hard and my
experience is that it doesn't equip them with the general
understanding of programming that we really want them to get from the
first programming course. I'm not sure about the Electrical
Engineering students but the Engineering Mathematics students tend not
to use C/C++ once they have covered Matlab and just use Matlab for all
future projects, including in situations where it is highly
inappropriate.

In our recent meeting I proposed that Python should be the first
programming language, and others proposed that Java should be the
second. So we're currently evaluating the option of having Python in
the first semester followed by Java in the second. Both courses would
have to be created from scratch meaning that we would need to draw a
complete outline and syllabus by mid-January in order to roll this out
for the next academic year.

I think that the benefits of this would be that using an "easy"
language would be less distracting while we introduce the general
concepts of programming. What we really want is for the students to
focus on things like "why would I write a program?", "what kind of
things can I do with a program?" and "how would I go about writing a
program that does X?". Ideally by the end of the course we want that,
given a description of a simple command line program that would
perhaps calculate something or do some simple data processing, then
the students would feel confident that they could do that. I think
that using C distracts them from learning these more important general
lessons as they struggle with simple things like how to print output,
or avoid segmentation faults. Also ideally they would continue to use
the language, where appropriate, for subsequent project work (which is
when they would *really* learn the language).

Some of the objections to the idea that were voiced in the meeting were that:
1) Some people felt that Python is not an "industry standard" unlike
C/C++/Java and that it is not as good for employability.
2) Students should learn to program in a statically typed language
because it leads to good programming discipline.
3) Python is too close to Matlab (which is considered essential for
some industries our students often go in to).
4) It is better for students to be introduced to programming with a
low-level language so that they gain a better understanding of how
computers "really work".
5) Learning to program "should be painful" and we should expect the
students to complain about it (someone actually said that!) but the
pain makes them better programmers in the end.

I'm particularly interested to know if anyone can share experience of
switching to teaching Python as a first programming language in a
similar context. A written up case study that I could circulate among
the relevant staff would be especially useful.


Thanks in advance,
Oscar

 

[rusi]

Hi all,

I work in a University Engineering faculty teaching, among other
things, programming. In our last meeting about improving our teaching
syllabus and delivery we've identified the first year programming
courses as an area where there is room for improvement and we're
considering (mainly on my suggestion) switching to using Python as the
first programming language that we use to introduce our students to
programming. I'm interested to know if anyone can share experience of
a similar situation or can point to any case studies about this.

1 Some Background
=================

Early in my teaching career - 1988 -- I experienced what it means to
switch from Pascal to Scheme to teach programming. And in 2002 I
swtiched to using python. I may talk a bit about this but before
that…


2 Some Philosophical Context
============================

Some years ago I read in a book (I think it was called "Heart of
Philosophy") about the difference between 'ideas' and 'concepts.'
Ideas are large vague touchy-feely things like freedom, love, justice
etc; things that matter but poets deal with better than intellectuals.
Concepts are the basic currency for an academic. In a typical 1-hour
class you deal with a few and in a lifetime you deal with thousands;
in short they are a dime a dozen -- especially if you are an academic.

And yet if you have a conscience you'd know that covering the concepts
specified in a formal printed syllabus is cheating. What really needs
to be conveyed are a few ideas:
- modular code
- code invariants
- abstractions
- Syntax, semantics and the large grey in between which for want of a
better word we may call 'structure'
- Recursion much wider than people think
see http://blog.languager.org/2012/05/recursion-pervasive-in-cs.html
- Interpretation
see http://blog.languager.org/2013/08/applying-si-on-sicp.html
- Computable and non-computable
- The meaning and significance of the word 'code'
- (Even more vaguely) beautiful (and ugly) code

Before reading on, I suggest you think what for a while what for you
are important/core ideas and then what vehicles/mediums are
conducive/obstructive to them.


3 My Prejudices
===============

Historically I've been associated with functional programming. While I
am not so passionate about it as when I was half my age. still I'd
say:

- FP *as a philosophy* collects a bunch of stuff -- technology,
practices, culture -- that conduces to good programming even for
kids who after the course never use FP *as a technology*

See http://blog.languager.org/2012/10/functional-programming-lost-booty..html

- By contrast OOP is mostly (at best) clerical common sense --
organizing libraries to be easily searchable is better by data than
by code. At worst OOP is hogwash -- inheritance.

And so…
- Python which can be quite functional, imperative and object oriented
has a rather special place. Because it is object oriented you will
be able to use it to silence those who are subscribed to that
religion. Because it is imperative you can write straightforward
code -- 'scripts' -- without undue fanfare Because it is functional
(well almost -- I have some beefs in this regard) you can use it as
a vehicle to actually convey important *ideas* in short space and
time

- For me Lisp (closely followed by APL) are the ultimate in
programming paradigms. However they are not serious technology in
2013. [Even the birthplace of Scheme -- MIT -- has switched to
python]. And so in 2013 python occupies a sweet spot in the sense of
being academically clean and realistically usable.

- That said there are some important elements of FPLs, most notably a
polymorphic type discipline, that are sorely missing from python.
Unfortunately Haskell is much harder to teach/learn than python and
with each new addition only gets harder. So python remains even
with its lacks, an academically sound language.

4 CS-Edu Writings
=================

My CS-101 syllabus from the early 90s --
uses gofer a predecessor of a predecessor of Haskell
http://www.the-magus.in/Publications/ip.pdf

Some more general CS-Edu related writings, containing strewn about
"FP is a good idea"
http://blog.languager.org/2011/02/cs-education-is-fat-and-weak-1.html
and following 2 posts

 

[rusi]

5) Learning to program "should be painful" and we should expect the
students to complain about it (someone actually said that!) but the
pain makes them better programmers in the end.

Yeah this will get some people's back up -- Atrocious! Preposterous! etc

Change the word 'pain' to 'taxing' 'hard' 'challenge' etc and there is much
truth in it. Here is Joel Spolsky on why Java is a poor language for
this reason: http://www.joelonsoftware.com/articles/ThePerilsofJavaSchools.html

 

[Gregory Ewing]

That's like saying that when teaching woodwork we shouldn't
let people use hammers, we should make them use rocks to
bang nails in, because it will make them better carpenters
in the long run.

 

[Chris Angelico]

That's like saying that when teaching woodwork we shouldn't
let people use hammers, we should make them use rocks to
bang nails in, because it will make them better carpenters
in the long run.

But in teaching woodwork you SHOULD let people use basic tools, and
not just a CNC lathe. Or in the most extreme sense, putting together
IKEA furniture is not carpentry, and neither is picking from an
extremely limited toolbox programming - which is why "Build a program
without writing a line of code" systems are junk for anything
complicated. (Occasionally, VERY occasionally, it's possible to use
the simple drag-and-drop system to get you 90% of the way, and then
fill in the rest yourself. Usually, you'll end up fighting the system
as soon as you do something the author didn't intend.)

Programming shouldn't be painful just for the sake of making it
painful. But you should be programming, not just solving a Sudoku
puzzle. It should be possible for a programmer to develop a unique
program that does a unique thing, and if that's beyond the scope of
the system, the system isn't a programming system. (Might still be a
useful system, of course, but it's not programming.)

ChrisA

 

[Gregory Ewing]

But in teaching woodwork you SHOULD let people use basic tools, and
not just a CNC lathe.

Programming shouldn't be painful just for the sake of making it
painful.

That's the only point I was trying to make. Pain in and
of itself doesn't help anyone to learn anything!

 

[Dennis Lee Bieber]

That's like saying that when teaching woodwork we shouldn't
let people use hammers, we should make them use rocks to
bang nails in, because it will make them better carpenters
in the long run.

NAILS????

Nails were verboten in my high school wood working class...

We used dowels and glue; chisels to carve dove-tails; etc.

 

[Denis McMahon]

NAILS????
Nails were verboten in my high school wood working class...
We used dowels and glue; chisels to carve dove-tails; etc.

We were allowed to use screws, but they had to be brass, not steel, we
had to drill appropriate clearance and pilot holes, and countersink where
appropriate.

And god help you if you deformed the slot in a brass screw head by over
tightening - I think that may have been why they made us use brass ones
only, so that such damage was easier to spot and more likely to happen.

And yes, I can dovetail, mortise and tenon, dowel etc etc etc.

 

[Larry Martell]

We were allowed to use screws, but they had to be brass, not steel, we
had to drill appropriate clearance and pilot holes, and countersink where
appropriate.

Ohhhh we used to DREAM of using screws! We were given steel shafts and
had to tap the threads into them with our teeth.

 

[Grant Edwards]

NAILS????

Nails were verboten in my high school wood working class...

We used dowels and glue; chisels to carve dove-tails; etc.

GLUE???

 

[Neil Cerutti]

NAILS????

Nails were verboten in my high school wood working class...

We used dowels and glue; chisels to carve dove-tails; etc.

....

You lucky BASTARD!

We had to build bookcases out of banana leaves held together with
our own spittle.

 

[Wolfgang Keller]

I'm particularly interested to know if anyone can share experience of

switching to teaching Python as a first programming language in a
similar context. A written up case study that I could circulate among
the relevant staff would be especially useful.

Just one experience from the "other" (student's) side.

When I started to study engineering science in 1991, Pascal was the
"first language" at the university in question (there were no
programming classes at highschool over here at that time yet). The class
was quite motivating and taught me some essential basics, I think.
Although issues such as object-orientation or event-based (GUI)
programming were not even mentioned, which is something that I'm
desperately missing today.

When I went to a different university (in 1993), still in engineering
science, they used C as the "first language" in the class there. The
result was that I tried (and succeeded) to pass that class with the
strict minimum of effort possible and deliberately forgot everything
that I had to learn about C as quickly as possible afterwards. I was a
"very good" student back then otherwise, so this was not due to
general laziness. What that class has taught me, essentially, was to
*hate* C. And it was not an issue of bad teachers. And they didn't mean
to make me hate C, after all, it was them who had chosen that language.
I never ever used C for anything (outside of that class). And ever
after that experience, I avoided all languages that were even remotely
similar to C, such as C++, Java, C#, Javascript, PHP etc.

In numerics classes and for research projects, I had to learn and use
Fortran, which was easy after the introduction with Pascal. The
teachers who taught me Fortran easily were the same as those who made me
hate C.

Then, I accidentally got in touch with Python (in 1994 iirc) and
thought it was interesting and useful. In fact Python is the only
programming language that I ever learned without being obliged to do
so. And the only one that I keep using whenever I have the choice.

Since then, the university that once used C as a "first language"
has switched to Python. Which is a good thing, imho. If I had had to
learn the basics of programming with C instead of Pascal, I most
certainly would have avoided anything even remotely connected to
programming ever since, even "office automation" through scripting
(which is what I use Python for today).

Sincerely,

Wolfgang

 

[Chris Angelico]

And ever
after that experience, I avoided all languages that were even remotely
similar to C, such as C++, Java, C#, Javascript, PHP etc.

I think that's disappointing, for two reasons. Firstly, C syntax isn't
that terrible. You might prefer Python syntax to it, but it's
undeniably better than several of its predecessors (I do not want to
write in COBOL, tyvm!), and there are recent languages that manage to
get some things so crazily backward (like abolishing operator
precedence so 2 + 3 * 4 = 24 not 14) that I wouldn't want to use them.
And secondly, C is very much the language of Unix. Sure, its best job
is implementing high level languages so day-to-day code doesn't need
to use it, but it's still important when you need to get to some
lower-level facilities. For those two reasons, I think a basic working
knowledge of C is useful for working with computers, networking,
pretty much everything these days. It won't break your brain to
understand multiple styles, and it might help you to remember why it
is you love Python syntax so much

Last time I had to do some C work, I was reminded just how amazingly
convenient a high-level string class is... all I wanted to do was
concatenate a bunch of strings with spaces between them, and I had to
go through so many hoops!

" ".join(list_of_strings)

Et voila.

ChrisA

 

[Wolfgang Keller]

And ever after that experience, I avoided all languages that were

I think that's disappointing, for two reasons. Firstly, C syntax isn't
that terrible.

It's not just the abysmally appalling, hideously horrifying syntax. At
about everything about C is just *not* "made for human beings" imho.

It's just an un-language that gets at about everything wrong. Sort of
like Microsoft's products.

Sincerely,

Wolfgang

 

[Ned Batchelder]

It's not just the abysmally appalling, hideously horrifying syntax. At
about everything about C is just *not* "made for human beings" imho.

I've never heard C syntax reviled quite so intensely. What syntax do
you like, out of curiosity?

 

[rusi]

I've never heard C syntax reviled quite so intensely. What syntax do
you like, out of curiosity?

I had a paper some years ago on why C is a horrible language *to teach with*
http://www.the-magus.in/Publications/chor.pdf

I believe people did not get then (and still dont) that bad for
- beginner education (CS101)
- intermediate -- compilers, OS, DBMS etc
- professional software engineering

are all almost completely unrelated

 

[Chris Angelico]

I had a paper some years ago on why C is a horrible language *to teach with*
http://www.the-magus.in/Publications/chor.pdf

I believe people did not get then (and still dont) that bad for
- beginner education (CS101)
- intermediate -- compilers, OS, DBMS etc
- professional software engineering

are all almost completely unrelated

Yes. In esr's essay on becoming a hacker[1] he says:

"""There is perhaps a more general point here. If a language does too
much for you, it may be simultaneously a good tool for production and
a bad one for learning."""

Definitely true, though I think it has exceptions.

[1] http://www.catb.org/esr/faqs/hacker-howto.html

ChrisA

 

[Rick Johnson]

NAILS???? Nails were verboten in my high school wood
working class... We used dowels and glue; chisels to carve
dove-tails; etc.

That could be a result of two possibilities:

1. Your high school years were before the great war, or:
2. Your wood shop teacher was a Luddite, a sadist, or both!

FYI: Fastener technology has come a long way since the fall
of the of the "Amish empire". All that laborious joinery has
been surpassed by mass production of helical threads and
pneumatic drivers. What once took a "master craftsman" an
entire day to build could now be built by a novice in mere
minutes.

Dovetails are nothing more than sadistic nostalgia --
they give old men a "chubby" and young men a nightmare.

When are we going to realize that the goal, *ahem*, OUR
GOAL, is to delegate minutiae DOWNWARDS, building the
collective knowledge base layer by layer...

ABSTRACTIONS people, ABSTRACTIONS!!!

Because, when you've got all your mental focus attuned to
carving intricate inter-meshing teeth into dense hardwoods
using razor sharp hand tools, you will be unable to see the
big picture, and furthermore, you might slip and cut your
finger off!

 

[Roy Smith]

Dovetails are nothing more than sadistic nostalgia --
they give old men a "chubby" and young men a nightmare.

There is nothing more satisfying than cutting a set of dovetails by hand
and having them glide together like silk, the first time you test-fit
them, with no daylight visible anywhere.

Someday, mine will be like that

 

[Mark Lawrence]

There is nothing more satisfying than cutting a set of dovetails by hand
and having them glide together like silk, the first time you test-fit
them, with no daylight visible anywhere.

Someday, mine will be like that

I suspect that your manual skills are rather better than mine. One of
my favourite expressions, perhaps because I only ever heard my dad use
it, is "like watching a cow handle a shotgun".