Data downloading... complete!

Ok here it is again.
Today, I'm happier than yesterday.. just because the things went as expected and I can go to sleep earlier...

This is how it looks the new experiment:

That chart display google stock quote (on a predefined period) integrated with pycha library and gtk3!

What I learnt
If you want to:

• draw on a GTK3 drawing area, you need to register to "draw" event.The "expose" event doesn't exist anymore.
• update a drawing area widget, you must call queue_draw on that widget
• get the dimension and position of a widget, you can call the methoed "get_allocation()" on that widget. This methoed give back a Rectangle object with this properties: x,y,width,height.
• plot with pycha, you have to create a context from the drawing area widget and from the context a surface, than pass the surface to pycha. More info on this point soon.

Yahoo Finance and Stock Quote Data
The stock quote data is obtained from Yahoo Finance, thanks to a web services present on their portal.
Thanks to Corey Goldberg with his library ystockquote obtain these data is a pretty easy task.
I have only to understand how much deep I can go with this script and if it is enough for what I'm looking for...
I also don't know where I can find the right keyword for stock quote companies: Google is GOOG , Apple is AAPL but I don't know where to find a list of these keywords.. or better a webservices to query.

After this research.. I need to pass to design & a bit of mockups!
 

Lack of documentation

Yesterday I spent a lot of time trying to plot a Chart in a Gtk Drawing Area, using quickly, Glade3, pygtk and pycha.

Some criticism about these tools:

• "hackish" style... you fix some problem thanks god to people like this: http://somethingididnotknow.wordpress.com/2012/01/27/retrieve-the-window-object-from-widgets-with-pygobject-gtk3.
• general lack of documentation. what you find around the web is usually deprecated and it doesn't work when you try it
• the gtk documentation is mainly in C, not in python, and sometimes have a C function called pippo() doesn't mean it exists the equivalent python function pippo()..but something like pyPippo()....
• when you need a library for a simple task, like plotting on a screen, you can find a lot of solutions, but find the one that just works , it is hard. Many library examples just doesn't work.. you have to find the solution. Read this http://detrasproject.wordpress.com/2011/04/04/show-graphs-using-pygtk/ Also if you don't want plot chart, read the post to understand what I mean. It's not coding.. it's hacking.
• Trying to plot a line chart inside a drawing area...it has been a bad experience.. and the result not satisfying for now... it looks good but there are a lot of bug to fix.

 

a prototype.

Quickly, pygtk, glade etc are great tool.. but Ubuntu need documentation, keeping it updated with examples and easy to find tutorial on "how to solve a simple task" or a page with the most important and working library for solve a task.
The hackish approach is not for all, we are in 2012.

This is not an attack to ubuntu community or in general to opensource.
Instead it is an important point, where community should think and improve.

I will post later the recipe for plot a pycha inside a GTK window made with Glade.

Planning and some code

For many reasons, the only way I had to find a place for ubuntu 12.04 was some space on Virtualbox.
Ubuntu on Virtualbox is quite fast to don't regret a real machine.

I have seen some parts of the video recorded from UbuntuDevelopers on this youtube channel: http://www.youtube.com/user/ubuntudevelopers
If you are new to pygtk, glade and quickly I suggest to follow those videos.

Planning
From now on, I have around 15 days to produce something good for the competition..
The 15 days will be splitted like this:

• 3 days experimenting, searching and understand new library in python: fetch webservices,  plot graphs (at least lines) and tools pygtk/glade, quickly.
• 4 days for design
• 4 days for programming
• 1 day for testing
• 1 day for submission
• 2 days extra time.. I know those days will be used in some way.

1st Problem
Yes, 1st problem: I desperately need to find a way to plot "cool" graphs with python.

I searched a bit and what I've found is not satisfying me enough.

I don't have the time to create a new library for plot graphs like I want..

Maybe, at the beginning I will use matplotlib (see this tutorial http://www.thetechrepo.com/main-articles/465-how-to-create-a-graph-in-python ) and I will try to improve how graphs looks on the screen only if I will have the time to do it..
I hope matplotlib is able to draw directly on a Gtk Drawing Area... I don't want to save on disk the image than load an image on the Gtk Drawing Area..... it is a sad approach.