I'm trying to make a macro for OpenOffice Calc that will toggle the background color of cells containing a user-specified value. Since I don't know OpenOffice Basic and have no desire to learn it, I'd like to write my macro in Python.
The trouble is, I can't find any useful documentation on how to write Python macros. From the reading I've done, it appears that I can't set up a dynamic environment from where I can examine the appropriate object(s) themselves, so I'll have to rely solely on documentation. Where can I learn how to write my macro?
EDIT:
I already know about "Python as a Macro Language," but it only answers where to put Python files. It says nothing about the API, how to search for and modify cells, etc.
In addition, there's no information about XSCRIPTCONTEXT, which OOo apparently provides as a global variable. Since I can't run interactively, I can't really interrogate that variable to learn about it.
EDIT 2:
I've found a number of pages that give bits and pieces of info, but they're either terribly incomplete or they assume a comprehensive pre-existing knowledge of the UNO API. So far, I haven't found anything useful. I simply don't have the time to try to learn the entire API just so I can understand one portion of it--especially since I'd have to learn C++ just so I could understand the syntax used in the documentation.
I went through the same motions and so wrote a blog post to share with others what I have learned. Pity that now (almost six years later) the documentation and examples are still so scarce.
For learning the api, check out the two helper functions in dev.py
https://onesheep.org/scripting-libreoffice-python/
About your specific need to explore XSCRIPTCONTEXT - it is not available when running through the socket, but you can explore the interface here:
http://www.openoffice.org/api/docs/common/ref/com/sun/star/script/provider/XScriptContext.html
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I am learning Python and how to make classes. I was curious how the classes are made inside Python itself! For example, in datetime.py (I find it by googling) I was checking how they used __add__ or __sub__ which is using "if isinstance(other, timedelta):" that was an interesting learning. Also, I am learning what professionally written programs look like.
My question is how can I find the source codes of internal classes and functions inside Python, for example, I am interested to see how they implement add in print(), that can print(1+2) -> 3 and
print('a'+'b') -> ab
The source code for the reference implementation of Python is available here at their GitHub mirror. However, it's worth noting that large parts of the Python language are implemented in C, including the core engine and many of the standard library libraries. Really understanding how everything is implemented under the hood requires a fair amount of C fluency.
ipython is a great tool for exploring how things work. Just add "??" after a function or other callable, and it show the code when possible, ie. when it's "pure python".
Eg:
import this
this??
Python is an open source language which means the source code is available to any interested party. I would suggest looking at the source files on the machine you are using or looking at the CPython Github repo.
print() is a built in module. It is written in C and the source can be viewed in the file bltinmodule.c.
You may also find it useful to learn about the functions available in Python for getting help, like help() (documentation available here). To learn about the print() function you can call:
help(print)
I recommend reading the Beginner's Guide as a starting point for more resources.
At this moment I am searching documentations or trying to make documentations for the XML-Code which builds the script boxes in Choregraphe. For example, like you could see in the next images (1 and 2): what does „Input name="Multiplicand" type="2" type_size="1" nature="1" inner="0"“mean in the basic script boxes just like “Multiply.py”? It would mean one variable as input value in type number with "onEvent" in choregraphe graphic interface according to the image3, I guess.
It's very hard to find them on the official documentation website from Aldebaran or even by Google results. In principle I could already find it out with just trying to change the values and see the changes in choregraphe, but it's not very smart and takes a while. At this point, I’m really forward to hearing from you. That would be very helpful for the next students who want to understand more about choregraphe and who want to build choregraphe script boxes by themselves in Python code level.
Yes, that "Multiplicand" you see in the xml is the input you can edit via the gui.
You can create and edit Choregraphe boxes entirely through the GUI, editing their inputs, outputs and parameters; I recommend doing that instead of touching the XML; because the exact format used in the .xar file may change in future versions. I have used Choregraphe quite a bit and have never felt the need to directly edit the .xar (except maybe when resolving git conflicts, but that was years ago and since then we've been avoiding having to ever merge a .xar file).
I'm relatively new to Python. I come predominantly from a C++ background, and C++ is a strongly and statically typed language, hence type checking is done at compile time and a function's prototype is self-documenting with respect to type information. Using a third-party library is often straightforward as long as they provide API reference pages such as those rendered by Doxygen. Upon finding a useful function, one can just look up its arguments' types and learn how to construct them. For example, I can easily figure out how to do most things in WxWidgets just by perusing the reference pages.
I'm currently working on a project in Python in which I need to manipulate font files. For this I'm using the FontTools package, but the documentation is lacking, and there are few tutorials online. I've been trying to glean as much as I can from the docstrings.
The question that's puzzling me right now, is how I'm meant to actually do anything when I don't know what types any function takes?
I have a Python code that needs to be able to execute a C++ code. I'm new to the idea of creating libraries but from what I have learned so far I need to know whether I need to use static or dynamic linking.
I have read up on the pros and cons of both but there is a lot of jargon thrown around that I do not understand yet and since I need to do this ASAP I was wondering if some light can be shed on this from somebody who can explain it simply to me.
So here's the situation. My C++ code generates some text files that have data. My Python code then uses those text files to plot the data. As a starter, I need to be able to run the C++ code directly from Python. Is DLL more suitable than SL? Or am I barking up the completely wrong tree?
Extra: is it possible to edit variables in my C++ code, compile it and execute it, all directly from Python?
It depends on your desired deployment. If you use dynamic linking will need to carefully manage the libraries (.so, .dll) on your path and ensure that the correct version is loaded. This can be helped if you include the version number in the filename, but then that has its own problems (security... displaying version numbers of your code is a bad idea).
Another benefit is that you can swap your library functionality without a re-compile as long as the interface does not change.
Statically linking is conceptually simpler and practically simpler. You only have to deploy one artefact (an .exe for example). I recommend you start with that until you need to move to the more complicated shared library setup.
Edit: I don't understand your "extra credit" question. What do you mean by "edit values"? If you mean can you modify variables that were declared in your C++ code, then yes you can as long as you use part of the public interface to do it.
BTW this advice is for the general decision. If you are linking from Python to C/C++ I think you need to use a shared library. Not sure as I haven't done it myself.
EDIT: To expand on "public interface". When you create a C++ library of whatever kind, you specify what functions are available to outside classes (look up how to to that). This is what I mean by public interface. Parts of your library are inaccessible but others (that you specify) are able to be called from client code (i.e. your python script). This allows you to modify the values that are stored in memory.
If you DO mean that you want to edit the actual C++ code from within your python I would suggest that you should re-design your application. You should be able to customise the run-time behaviour of your C++ library by providing the appropriate configuration.
If you give a solid example of what you mean by that we'll be able to give you better advice.
Yes it is possible!!
Try exploring subprocess module in python.
Following can be an example implementation of your scenario:
yourfile.cpp
#compilation
args = ['g++','-o','your_executable_name_with_path','yourfile.cpp_with_path']
your_compile = subprocess.Popen(args,stdin=subprocess.PIPE,stderr=subprocess.PIPE,stdout=subprocess.PIPE)
output,compilation_error = your_compile.communicate()
your_compile.wait()
#successful compilation then there will be execuatble
if not compilation_error:
#execuation
args = ['your_executable_name_with_path'] #command to run a an execuatble
your_run = subprocess.Popen(args,stdin=subprocess.PIPE,stderr=subprocess.PIPE,stdout=subprocess.PIPE)
your_code_output,runtime_error = your_run.communicate()
your_run.wait()
Further, you can tackle more cases and come up with an efficient design
I'm not quite sure how the idea of linking comes into what you are asking, but it sounds to me like you want to use something like SWIG, which allows you to create wrappers around C++ functions (and many other languages) which you can then call directly from your Python code.
Extra: is it possible to edit values in my C++ code, compile it and execute it directly from Python?
If I'm understanding this correctly, you want to use Python to change your C++ code, then compile and execute it? If this is the case, you may want to look into embedding the Python interpreter in your C++ program. This would mean doing things the other way around and having C++ run your Python script, instead of trying to do everything from Python.
I am trying to learn Python and referencing the documentation for the standard Python library from the Python website, and I was wondering if this was really the only library and documentation I will need or is there more? I do not plan to program advanced 3d graphics or anything advanced at the moment.
Edit:
Thanks very much for the responses, they were very useful. My problem is where to start on a script I have been thinking of. I want to write a script that converts images into a web format but I am not completely sure where to begin. Thanks for any more help you can provide.
For the basics, yes, the standard Python library is probably all you'll need. But as you continue programming in Python, eventually you will need some other library for some task -- for instance, I recently needed to generate a tone at a specific, but differing, frequency for an application, and pyAudiere did the job just right.
A lot of the other libraries out there generate their documentation differently from the core Python style -- it's just visually different, the content is the same. Some only have docstrings, and you'll be best off reading them in a console, perhaps.
Regardless of how the other documentation is generated, get used to looking through the Python APIs to find the functions/classes/methods you need. When the time comes for you to use non-core libraries, you'll know what you want to do, but you'll have to find how to do it.
For the future, it wouldn't hurt to be familiar with C, either. There's a number of Python libraries that are actually just wrappers around C libraries, and the documentation for the Python libraries is just the same as the documentation for the C libraries. PyOpenGL comes to mind, but it's been a while since I've personally used it.
As others have said, it depends on what you're into. The package index at http://pypi.python.org/pypi/ has categories and summaries that are helpful in seeing what other libraries are available for different purposes. (Select "Browse packages" on the left to see the categories.)
One very common library, that should also fit your current needs, is the Python Image Library (PIL).
Note: the latest version is still in beta, and available only at Effbot site.
If you're just beginning, all you'll need to know is the stuff you can get from the Python website. Failing that a quick Google is the fastest way to get (most) Python answers these days.
As you develop your skills and become more advanced, you'll start looking for more exciting things to do, at which point you'll naturally start coming across other libraries (for example, pygame) that you can use for your more advanced projects.
It's very hard to answer this without knowing what you're planning on using Python for. I recommend Dive Into Python as a useful resource for learning Python.
In terms of popular third party frameworks, for web applications there's the Django framework and associated documentation, network stuff there's Twisted ... the list goes on. It really depends on what you're hoping to do!
Assuming that the standard library doesn't provide what we need and we don't have the time, or the knowledge, to implement the code we reuse 3rd party libraries.
This is a common attitude regardless of the programming language.
If there's a chance that someone else ever wanted to do what you want to do, there's a chance that someone created a library for it. A few minutes Googling something like "python image library" will find you what you need, or let you know that someone hasn't created a library for your purposes.