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I've gotten to grips with the basics of Python and I've got a small holiday which I want to use some of to learn a little more Python. The problem is that I have no idea what to learn or where to start. I'm primarily web development but in this case I don't know how much difference it will make.
Well, there are great ressources for advanced Python programming :
Dive Into Python (read it for free)
Online python cookbooks (e.g. here and there)
O'Reilly's Python Cookbook (see amazon)
A funny riddle game : Python Challenge
Here is a list of subjects you must master if you want to write "Python" on your resume :
list comprehensions
iterators and generators
decorators
They are what make Python such a cool language (with the standard library of course, that I keep discovering everyday).
Depending on exactly what you mean by "gotten to grips with the basics", I'd suggest reading through Dive Into Python and typing/executing all the chapter code, then get something like Programming Collective Intelligence and working through it - you'll learn python quite well, not to mention some quite excellent algorithms that'll come in handy to a web developer.
Something great to play around with, though not a project, is The Python Challenge. I've found it quite useful in improving my python skills, and it gives your brain a good workout at the same time.
I honestly loved the book Programming Python. It has a large assortment of small projects, most of which can be completed in an evening at a leisurely pace. They get you acquainted with most of the standard library and will likely hold your interest. Most importantly these small projects are actually useful in a "day to day" sense. The book pretty much only assumes you know and understand the bare essentials of Python as a language, rather than knowledge of it's huge API library.
I think you'll find it'll be well worth working through.
I'll plug Building Skills in Python. Plus, if you want something more challenging, Building Skills in OO Design is a rather large and complex series of exercises.
The Python Cookbook is absolutely essential if you want to master idiomatic Python. Besides, that's the book that made me fall in love with the language.
I'd suggest writing a non-trivial webapp using either Django or Pylons, something that does some number crunching.
No better way to learn a new language than commiting yourself to a problem and learning as you go!
Write a web app, likely in Django - the docs will teach you a lot of good Python style.
Use some of the popular libraries like Pygments or the Universal Feed Parser. Both of these make extremely useful functions, which are hard to get right, available in a well-documented API.
In general, I'd stay away from libs that aren't well documented -
you'll bang your head on the wall trying to reverse-engineer them -
and libraries that are wrappers around C libraries, if you don't have
any C experience. I worked on wxPython code when I was still learning
Python, which was my first language, and at the time it was little
more than a wrapper around wxWidgets. That code was easily the ugliest
I've ever written.
I didn't get that much out of Dive Into Python, except for the dynamic import chapter - that's not really well-documented elsewhere.
People tend to say something along the lines of "The best way to learn is by doing" but I've always found that unless you're specifically learning a language to contribute to some project it's difficult to actually find little problems to tackle to keep yourself going.
A good solution to this is Project Euler, which has a list of various programming\mathematics challenges ranging from simple to quite brain-taxing. As an example, the first challenge is:
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
And by problem #50 it's already getting a little tougher
Which prime, below one-million, can be written as the sum of the most consecutive primes
There are 208 in total, but I think some new ones get added here and there.
While I already knew python fairly well before starting Project Euler, I found that I learned some cool tricks purely through using the language so much. Good luck!
Search "Alex Martelli", "Alex Martelli patterns" and "Thomas Wouters" on Google video. There's plenty of interesting talks on advanced Python, design patterns in Python, and so on.
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I was reading about Go, and I can see that it's very good and can be a language used by many developers in some months, but I want to decide a simple thing: Learn Go or improve my Python or Ruby knowledge?
Years developing with Python: 1
Years developing with Ruby: 0.3
If you're just looking to have fun and expand your horizons, then I'd learn Go, since you already know some Python.
If you're looking to improve as a developer, I'd personally recommend working on an actual project (using Python, as it's the language you have the most experience with):
This will take your (Python and general) programming skills to a whole new level
If you choose an interesting project, for example a semi-popular open source project, you'll even have some concrete result to show for your extra work. This will help your resume, help you meet other people interested in programming, etc.
I personally believe that spending the time you would have spent learning a new language by coding actual things you can use, is usually a net win (unless of course, like I said, you're just doing it for some fun recreation or relaxation).
In reality, you should do both; if it's what you want. For me though, out of the two, I'd only look at Python. I have no real interest in languages that are so new.
It depends on what your goals and your needs are.
If you're looking to develop your skills for a job, then go with Python or Ruby. You're unlikely to see Go show up in the workplace for quite some time (if ever) unless you're working at Google. (Even then it's questionable.)
If you want to have fun, do what you want. I think the best decider is, pick a project you want to work on and then choose the language that is best suited for that project.
Other things to consider:
Each language is suited to certain tasks. Go is compiled into machine code, whereas Python and Ruby run in interpreters. Go lends itself to somewhat lower level work. It's also good for concurrent tasks. Higher level tasks might be more suited for Python or Ruby.
Go is an experimental language that's likely to experience changes. These changes may be backward incompatible. If you learn it now, in 6 months or a year you may have to re-learn some of it because it's changed. That said, it can be fun to be a part of something that's on the bleeding edge. And if it does happen to become "the next big thing," you're in on the ground level.
How long have you been working with Python?
If it were me, I'd do my best to maybe get a working knowledge of Go (basic syntax, some familiarity with unique language features), and continue with Python as I normally would.
Eventually you might come up with a small project that Go seems suited for (or you can come up with one now!) and really dive into the language that way.
There's no reason to limit yourself to just one. :)
It's up to you. You should probably do both if you can, because that way you will have more tools on your metaphorical programmer's belt.
There are a number of things that I think are worth considering whenever I'm in a similar dilemma.
Is a new language (not just unfamiliar, but actually new, like Go) likely to catch on? (If so, it will become practically NECESSARY to learn it, rather than just a good idea.)
You will need to spend some time to learn the unfamiliar language. Will this time investment result in some sort of positive return? The obvious one here is development time (i.e., can you eventually get more done and get back the time you spent to learn it), but if the language is superior in other ways (runs faster or with less memory, is best for your particular problem domain) those might factor in too.
Will learning the unfamiliar language allow you to solve a relevant/important/urgent problem that cannot be solved with what you already know?
Unfortunately, none of us can tell you how to weigh each of these concerns. You'll need to think about it really carefully and come to the answer on your own.
First of all, it's a very very personal question, and my first recommendation will be , if you think so, try Go for one month or so, learning the basics, and then deciding... Each one has the mind fitted more to some particular languages than another...
I also would recommend keep using both Python and Ruby, if you're interested, you have enough experience to use them comfortably (I think), so the next months you could experience a great boost in your experience using them...
For an strict utilitarian point of view, learning Go extensively could be a risk move, but worthy if begins to being using and you're one of the very few people with some experience when everyone are just beginning to learn the syntax...
These two languages accomplish different goals. Go is only 20% slower than C. If you want crazy speed and easy parallelism, then learn Go. However, readability was not a design goal. Also, it has no exceptions. It can be used for real-time products though ...
IMO you should improve your Python knowledge. Python is a widely adopted language, whereas
Go is still at a very, very early stage and there's no reason to believe that it will become successful.
From a purely utilitarian perspective, you will get a lot more value from learning Python.
It's not easy to answer this without knowing how good your Python is, or what you do, or where you'd use Go. If you're looking for employment, I suspect Python is the way to go. I'd be surprised to find anyone is using Go for major projects at the moment (outside Google).
Note also that Go is by no means finalised. See here for the Go roadmap, and note the potential changes in the future. So you may be trying to hit a moving target currently.
Python is a available for most operating systems, it's generally accepted as a scriptin language, and it has matured to production quality.
Go is a research language that's only available in beta quality on Linux and OS X. Nowhere else. It's interesting from an intellectual point of view in that you can learn and apply a few concepts (typed channels combined with easy multitasking) that are otherwise difficult to use.
As for Go, you might perhaps take a look at AT&T's "Plan 9" operating system first. It comes with a programming language called "Aleph" with also is C-based, has channels and multitasking. Looks to me like Go is a reimplementation of Aleph on more main-stream operating systems.
I heard that Python is easy and powerful, but I don't know if I'm on the right track to learn it. I learn from online tutorials, I know basic maths calculation and printing strings, but how long will it take to develop something useful? I don't really know the exact uses of Python, though.
I'm not exactly sure what you're looking for, but I think one or more of the following may be the next step you're looking for.
Perhaps you would like to use a variety of different protocols for a networking program, you could check out Twisted.
Or perhaps if you would like to make a web application or blog you can check out Django.
Or perhaps you would like to make a GUI application, you could take a look at TkInter.
Or perhaps you would like to get into game programming, you could take a look at Pygame.
Or perhaps you would like to ... you can take a look at the Python Package Index.
How long will it take? This depends on your programming background in general. The best way is simply to jump into the topic you're interested in and start on a mini project.
Python is a general purpose language. You can use it to make a lot of different things, but it's best suited at stuff that doesn't require a lot of speed, since the high level features have a performance cost.
It's hard to tell how long it will take you to develop something useful. The other day I made a script to help on a small computer administration thing. You could do that with a week or two of experience (or maybe less), depending on your previous programming knowledge and the amount of time you put into studying. However, if you want to make something bigger (maybe an audio player, an IM client, mid-sized stuff like that), you probably need some weeks or months of practice. It depends a lot on the time and energy you invest in programming.
I'd suggest to follow either the official tutorial or Dive Into Python.
In general, it depends on you. Python can be used for simple or complex stuff, and for many different applications. It depends on what you want.
Have a look at Mark Pilgrim's freely available book called Dive Into Python. I think it's a better choice to start with than online tutorials. The best way to learn a language is to start to work on a project. As I read this book, I started to implement a simple image viewer. As I advanced with the book, I could refine the project progressively. Invent something that is interesting to you.
I also suggest you taking notes when you learn a programming language. When you learn something that can be useful later, make some notes with a simple example, e.g. how to read a text file line by line, convert int to str, convert str to int, basic list operations, etc. Later on you can use these building blocks in a larger project.
Like every other programming language In order to learn Python you need to write a program with it.
Find a pet project and use python to code it. I also recommend Dive into python" (like anyone else that answered your question).
A few months ago I've decided to learn IronPython (.NET implementation of python), I'vve started by reading "Dive into python" and a few tutorials and then I've started coding a simple board game using IronPython (you can read about it in my blog).
In order to learn a new programming language you need to use it and then you'll know how and where to use it.
The best way to learn how to do something useful is come up with something useful you want to do. Make sure it's not way out of your league, then do research to accomplish it. That's how a lot of programmers learn languages.
What other programming background do you have? What programming interests do you have -- web apps, numerical / scientific computations, games, ...? Python is good at many different things, for both beginners and experienced programmers, but the most fruitful approach(es) to it do depend on what you already know, and what really interests you!-)
Bram who invented bittorrent with python says python is good for writing protocols in addition to aforementioned webapps, games and general purpose. Compared to Java python solves same problem in less code and less ways in longer development and VM time where Java has more ways solve same problem in more code and faster VM and faster development time.
Making a comparison between Python, and other languages would not help, as there is always somebody who would find a reason to prefer one language instead of another.
If you want a scripting language that is powerful, but that it is easier to read than perl, that doesn't have a curly bracket syntax, and that allows you to learn something about object oriented programming, then Python is the language for you.
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I'm working with a Python development team who is experienced with programming in Python, but is just now trying to pick up TDD. Since I have some experience working with TDD myself, I've been asked to give a presentation on it. Mainly, I'm just wanting to see articles on this so that I can see how other people are teaching TDD and get some ideas for material to put in my presentation.
Preferably, I'd like the intro to be for Python, but any language will do as long as the examples are easy to read and the concepts transfer to Python easily.
One suggestion I'd make is to start a coding Dojo group. It helps to start TDD from scratch with a group, with most of recommended best-practices and focus on TDD.
Its basic ideas is to take a simple challenge (like a program that transforms roman algarisms strings into ints), and start to code it, starting from simple inputs, and coding only when there's a test failing. It's not the focus of this to end the problem, but to start making it the right way.
Here's another link about it, from which I retrieved the following part:
There is a coding challenge that is announced beforehand.
There is a room with one computer attached to video screen.
The presenter explains the coding challenge and starts the coding. The presenter may or may not choose to have a co-pilot. If this is a Randori session, a co-pilot is usually assigned so that when the switch occurs, the co-pilot takes over for the coder.
One half of the pair is changed every 5 minutes if the session is Randori.
The coder should continuously explain what she or he is doing.
The coder should stop when someone from the audience falls off the sled (has a question about understanding what the pair is doing) -- and only continue when that someone is back on track again.
All coders use TDD (Test-Driven Development).
All produced code will be made publicly available using the Eclipse Common Public License.
The programming language to be used is announced in advance per session.
I was very pleased with the two-part article "Test Driven Development in Python" on O'Reilly's site:
http://www.onlamp.com/pub/a/python/2004/12/02/tdd_pyunit.html - waybackmachine
http://www.onlamp.com/pub/a/python/2005/02/03/tdd_pyunit2.html - waybackmachine 2/3 and 3/3
These really cleared up how to use Python's unittest module for TDD, as well as giving me a good dose of the TDD mindset.
Kent Beck's book gives some examples in Java and some in Python (to be honest, Kent doesn't strike me as a superstar in either language, judging from the example code in this book... but he definitely comes across as a superstar in TDD &c -- as well he should, given he's basically invented it as well as extreme programming, see his wikipedia entry).
Not in python but this is a good intro by jp boodhoo
http://www.bestechvideos.com/2008/06/28/dnrtv-show-10-jean-paul-boodhoo-on-test-driven-development-part-1-of-2
I think that the chapters covering testing in Dive Into Python are pretty good. They cover building a basic program from scratch using TDD.
Getting Started with Tdd in Java using Eclipse by Brett L. Schuchert
Is a set of screencasts about TDD in Java and in C#. It is starting from the scratch and teaching basics.
I started unit testing a handful of years ago, and I've read quite a few on it since my initial book.
However, my initial was "Test Driven" by Lasse.
For me, the author made it simple to understand.
Perhaps you could pull some info from it for your teaching.
And btw, I've taught TDD as well.
I have found that ensuring the audience understands how to use unit tests before going into TDD to be quite handy.
Good luck! :-)
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I'm a newbie to programming. I had 1 semester of computer science (we used java). I got an A in the course and was able to do everything assigned, however I'm not sure I really understood it. I ignored the text and learned by looking at sample programs and then trial and error. I was ahead of the class except for two guys who came in knowing java or another OOP language.
I'd like to learn Python. I'm also going to build a second PC from extra parts I have and use linux. Basically, I want to enhance my knowledge of computers. Thats my motivation.
Now on learning python are there any good programming theory books that would be useful? Or should I read up on more on how computers operate on the lowest levels? I don't think I know enough to ask the question I want.
I guess to make it simple, I am asking what should I know to make the most of learning python. This is not for a career. This is from a desire to know. I am no longer a computer science major (it also would not have any direct applications to my anticipated career.)
I'm not looking to learn in "30 days" or "1 week" or whatever. So, starting from a very basic level is fine with me.
Thanks in advance. I did a search and didn't quite find what I was looking for.
UPDATE: Thanks for all the great advice. I found this site at work and couldn't find it on my home computer, so I am just getting to read now.
My recommendation is always to start at the high level of abstraction. You don't need to know how logic gates work and how you can use them to build a CPU -- it's cool stuff, but it's cool stuff that makes a lot more sense once you've messed around at the higher levels. Python is therefore an excellent choice as a learning aid.
How to Think Like A Computer Scientist: Learning With Python is available on the Internet and is an excellent introduction to the high-level concepts that make computers go. And it's even Python-specific.
If you're looking to have your brain turned inside-out, SICP will do a good job of it. I don't recommend it as a first text, though; it's heavy going.
Both of these books are high-level. They won't teach you anything about the low-level details like memory structures or what a CPU actually does, but that's something I would reserve for later anyway.
D'A
Specifically for the Python part of your question I can highly recommend http://www.diveintopython3.net/ by Mark Pilgrim. That's free and pretty well structured.
Python is a nice choice, you will have fun!
http://www.pythonchallenge.com/
I think this Challenge is perfect to get in touch with major python strengths and there is a nice forum with a lot of interessting Python Threads for each Level.
A lot of this depends on what your overall goal is for learning Python. Are you viewing it as learning a second language or getting a better understanding of computers and how to effectively use a programming language?
From what it sounds like you want to gain a better understanding about computers and be a better programmer. Learning a new languages such as Python will probably not help you in this respect. I still recommend learning Python if you're interested, but once you have learned one programming language, much of learning a new language is getting familiar with the syntax and data types (usually).
You had mentioned you were unsure about understanding the material in the class you took. If you feel you don't understand fundamental concepts (such as loops, classes, etc), then learning Python will help your understanding of programming as most books/guides revisit these concepts (Learning Python, 3rd Edition should help with this). If you understand these concepts, but you are unsure of how to apply these concepts, then my recommendation would be to learn about data structures and common algorithms (e.g. sorting, searching, etc).
Speaking from personal experience, I didn't know how to apply what I learned from the introductory programming class to personal programming projects. Learning about data structures from a class helped solidify those concepts I had previously learned by providing algorithms/data structures that build off of this previous knowledge. This class also allowed me to think differently about problems in terms of using these data structures.
To learn about the different types of data structures, see: http://en.wikipedia.org/wiki/List_of_data_structures. Usually, each data structure is useful for a specific purpose (e.g. binary search trees are good for searching sorted information). Unfortunately, I don't have any book recommendations (our class didn't use a book). Googling "Data Structures" should be a good starting point.
Data structures also got me to think about how efficient an implementation is. The "complexity" of an algorithm determines how long a given piece of code takes to run. This makes it easy to compare other implementations and determine which is better.
I would also like to comment that when it comes to learning computer concepts, the best way to learn is by doing. A book/class can only explain so much, and the rest you have to learn on your own. Each person learns differently, and programming is a way of taking the material you read about and think about it in a way that is best understood by you.
I hope I answered your question. At this point, you don't really need to worry about the underlying hardware. This is useful to know if you plan on doing this as a career (which you aren't), or want to make optimizations specific to the hardware you're running on (in which case, you wouldn't want to use Python). Python is a good choice to learn about data structures as it implements a lot of them for you, but it's important to know what they are used for.
If you are still in school, take a data structures class and see what you think of it. If you like it, I'd advise reconsidering the role of programming/CS in your career. You don't have to major in it, but consider a minor or at least a position that makes use of these skills you are learning. I say this because despite this not being your major, you are interested in understanding how a computer works and taking initiatives such as learning Python, building your own computer, and installing Linux.
If you have any further questions, feel free to ask. Good luck!
Python is a high-level language, so it wouldn't give you much direct benefit to learn how computers operate at the lowest levels.
Don't get me wrong - I do strongly believe that the low-level operation of a computer, e.g. assembly language and hardware, is something that every good programmer should be familiar with, because it does help you program more effectively in whatever language you are using, high-level or low-level. But it won't make much of a difference in your Python coding until you've gotten quite a bit of experience. If you're just starting out with Python, I would suggest staying away from the low-level operation of computers and concentrating on the basics of Python for now. Once you're comfortable with that, you can move on to something like C and then it might be appropriate to start looking at some lower-level stuff.
As for what you should know... not much, I guess. Python is a great language to start out programming in. It keeps simple things simple but it's rich enough to let you work your way up to a high level of complexity. I'd suggest probably looking at a tutorial; the one I happen to know is on the Python website, but I'm not claiming it's necessarily the best one for you. A Google search should give you plenty to get started with.
I started Python (as my first programming language) few months ago. I would recommend Learning Python, by Mark Lutz to begin with. But keep in mind that the key to learn well is to be open-minded, patient and willing to work and look up for things you don't understand.
Have fun!
I would suggest looking at the online book at http://www.diveintopython.org/ to learn python.
As for python projects, I would try learning the Django Framework. It is a framework for building web applications. They have a great tutorial for getting started with it. This would also give you experience building a webserver on a Linux box.
enhance my knowledge of computers
Well, what do you exactly mean by that? Python, or any other high level language, are designed to actually hide all the nasty details. That's one of the reasons, why it's apt for non-pros like (e.g. scientist).
If you want to know how stuff actually work, you should learn pure C. But then again, if you're not planning to have any career related to SC, there's not much point to it. Learn some more advanced algorithms and data structures instead. That'll result you more interesting, useful and is platform- and language-agnostic.
Short answer: all of them
Long answer:
Learning your first language is always a challenge, and after your Java experience, a lot of other languages will seem a lot simpler. That said, the real challenge in learning programming languages is learning when to use a particular language -- you can find decent docs for whatever you choose when the time comes.
As a concrete start, hop over to wikipedia and browse their categorical list of programming languages, click on all of the names you've ever heard (and anything else that catches your eye) and if the article has a code example, give it a minute or two to sink in (the rest of the article will help, of course). The point here is not to master every single language (which is (1) pointless and (2) impossible), but to get a handle on what is out there. For any language, there is a handful of other languages like it, and if you can at least read one language in most of those categories, you will have mastered a fairly large chunk of the programming universe. When a new project comes up, and something about it reminds you of some language you found, you can just learn that language as part of doing the project. It may sound like a lot of work, but after, say, your fifth big language, you completely lose count and just accidentally learn new ones all the time without noticing.
When you stop relating to one language as your home-language, you'll be able to learn from examples in other languages even if you've never programmed in them. Personally, I've only written a few Haskell programs, but being able to read Haskell has exposed me to a lot of ideas that I could recycle in more practical Scala and Python programs (oh yeah, after you learn Python, give Scala a browse and you'll probably never use Java again)
Even finding the best language for the job isn't the whole story. Having a lot of tools in your toolbox lets you throw together amazing stuff in short amounts of time by writing each piece of your project in the easiest language your could. This may not be appropriate for all projects, but, boy, can you make some impressive demos.
It takes many years to get to the point where no programming language is totally foreign (or at least foreign for more than a day of hacking), but I think it is a very healthy and realistic long-term plan to attempt to conquer a representative sample of each rough category. Good luck!
Since Python wasn't my first language, I found the Python Cookbook helpful for learning
What Python was capable of
The idiomatic, of "pythonic," way to do something.
Programming language teaching has always been associated with a cliche statement while learning. "Write programs to learn programming". I too would suggest the same.
If you are going to start from basics. This is of course, the most suggested starting point. It is lengthy, but it is worth all the time. http://www.diveintopython.org/
Because you are into some Java, this might be even better for you. http://www.swaroopch.com/notes/Python. Start either python 2.x or 3.0. Me personally am a fan of python 3. But for a starter it could be hard to get samples, and references to programs online. So for you 2.x might be better. But I leave it upto you.
Like I started "Write programs..". You can start here.
http://www.spoj.pl/ - a programming challenges site, where you can choose from a wide variety of topics, mostly algorithms and has huge question database. Of course the choice of programming languages is upto you.
http://projecteuler.net/ - a mathematical questions site, here you just have to submit an answer, cheating is allowed here, so be free to borrow logic from others, but try writing the program yourself.
After you think you have gained sufficient proficiency in python, you can try recipes in this book python cookbook http://www.amazon.com/Python-Cookbook-Alex-Martelli/dp/0596007973.
For application development, after you think you can handle it, start on wxPython or PyQt. I personally would suggest PyQt. It is responsive, fast, and has decent development cycle, I have not used WxPython for long, but few programs I wrote, long back, didn't feel so great. Yet again, its upto you.
I've been programming Ruby pretty extensively for the past four years or so, and I'm extremely comfortable with the language. For no particular reason, I've decided to learn some Python this week. Is there a specific book, tutorial, or reference that would be well-suited to someone coming from a nearly-identical language, or should I just "Dive into Python"?
Thanks!
A safe bet is to just dive into python (skim through some tutorials that explain the syntax), and then get coding. The best way to learn any new language is to write code, lots of it. Your experience in Ruby will make it easy to pick up python's dynamic concepts (which might be harder to get used to for say a Java programmer).
Try a python tutorial or book on learning python.
After running through some tutorials on-line (the ones posted so far look pretty good), find a current Ruby project you've done (or are working on) and re-write it in Python. I've used this technique to transition from various languages, and it's helped enormously.
I started learning from the python tutorial. It is well written and easy to follow. Then I started to solve problems in python challenge. It was a really fun way to start :)
I suggest just diving into Python, it's similar to Ruby so you should have no problems:
http://www.diveintopython.net/