# use itertools.islice(iterable, [start,] stop [, step])
# to get selected results of a generator function ...
 
from itertools import islice
 
def fibo_generator():
    """
    a generator for Fibonacci numbers, goes
    to next number in series on each call
    """
    current, previous = 0, 1
    while True:
        yield current
        # use a tuple swap
        current, previous = previous, current + previous
 
print "show Fibonacci number for n = 10:"
for k in islice(fibo_generator(), 10, 11):
    print k,
 
print; print
 
print "show Fibonacci series for n = 7 to 10:"
for k in islice(fibo_generator(), 7, 11):
    print k,

# use a Tkinter label as a panel for a background image
# note that Tkinter only reads .gif and .ppm images
# use the Python Image Library (PIL) for other image formats
# free from [url]http://www.pythonware.com/products/pil/index.htm[/url]
# give Tkinter a namespace to avoid conflicts with PIL
# (they both have a class named Image)
 
import Tkinter as tk
from PIL import Image, ImageTk
 
root = tk.Tk()
root.title('background image')
 
# pick an image file you have .bmp  .jpg  .gif.  .png
# load the file and covert it to a Tkinter image object
imageFile = "Flowers.jpg"
image1 = ImageTk.PhotoImage(Image.open(imageFile))
 
# get the image size
w = image1.width()
h = image1.height()
 
# position coordinates of root 'upper left corner'
x = 0
y = 0
 
# make the root window the size of the image
root.geometry("%dx%d+%d+%d" % (w, h, x, y))
 
# root has no image argument, so use a label as a panel
panel1 = tk.Label(root, image=image1)
panel1.pack(side='top', fill='both', expand='yes')
 
# put a button on the image panel to test it
button2 = tk.Button(panel1, text='button2')
button2.pack(side='top')
 
# save the panel's image from 'garbage collection'
panel1.image = image1
 
# start the event loop
root.mainloop()

>>>g = fibo_generator()
>>>print g[0:10]
0 1 1 2 3 5 8 13 21 34 55

# determine size of a given folder in MBytes
 
import os
 
# pick a folder you have ...
folder = 'D:\\zz1'
folder_size = 0
for (path, dirs, files) in os.walk(folder):
  for file in files:
    filename = os.path.join(path, file)
    folder_size += os.path.getsize(filename)
 
print "Folder = %0.1f MB" % (folder_size/(1024*1024.0))

print '\n'*35

# works on Windows or Linux, also Vista
import os
os.system(['clear','cls'][os.name == 'nt'])

#Boa:Frame:Frame1
 
import wx
 
def create(parent):
    return Frame1(parent)
 
[wxID_FRAME1, wxID_FRAME1BUTTON1, wxID_FRAME1BUTTON2, wxID_FRAME1BUTTON3, 
 wxID_FRAME1LISTBOX1, 
] = [wx.NewId() for _init_ctrls in range(5)]
 
class Frame1(wx.Frame):
    def _init_ctrls(self, prnt):
        # generated method, don't edit
        wx.Frame.__init__(self, id=wxID_FRAME1, name='', parent=prnt,
              pos=wx.Point(355, 138), size=wx.Size(255, 385),
              style=wx.DEFAULT_FRAME_STYLE, title='Frame1')
        self.SetClientSize(wx.Size(247, 345))
        self.SetBackgroundColour(wx.Colour(0, 128, 0))
 
        self.button1 = wx.Button(id=wxID_FRAME1BUTTON1, label='Load List',
              name='button1', parent=self, pos=wx.Point(16, 16),
              size=wx.Size(87, 28), style=0)
        self.button1.Bind(wx.EVT_BUTTON, self.OnButton1Button,
              id=wxID_FRAME1BUTTON1)
 
        self.button2 = wx.Button(id=wxID_FRAME1BUTTON2, label='Sort List',
              name='button2', parent=self, pos=wx.Point(16, 296),
              size=wx.Size(87, 28), style=0)
        self.button2.Bind(wx.EVT_BUTTON, self.OnButton2Button,
              id=wxID_FRAME1BUTTON2)
 
        self.button3 = wx.Button(id=wxID_FRAME1BUTTON3, label='Clear List',
              name='button3', parent=self, pos=wx.Point(136, 296),
              size=wx.Size(87, 28), style=0)
        self.button3.Bind(wx.EVT_BUTTON, self.OnButton3Button,
              id=wxID_FRAME1BUTTON3)
 
        self.listBox1 = wx.ListBox(choices=[], id=wxID_FRAME1LISTBOX1,
              name='listBox1', parent=self, pos=wx.Point(16, 64),
              size=wx.Size(208, 216), style=0)
        self.listBox1.Bind(wx.EVT_LISTBOX, self.OnListBox1Listbox,
              id=wxID_FRAME1LISTBOX1)
 
    def __init__(self, parent):
        self._init_ctrls(parent)
 
    def OnButton1Button(self, event):
        '''
        click button to load the ListBox with names
        '''
        self.listBox1.Append("Andreas")
        self.listBox1.Append("Erich")
        self.listBox1.Append("Udo")
        self.listBox1.Append("Jens")
        self.listBox1.Append("Bjorn")
        self.listBox1.Append("Heidrun")
        self.listBox1.Append("Ulla")
        self.listBox1.Append("Volger")
        self.listBox1.Append("Helmut")
        self.listBox1.Append("Freja")
        self.listBox1.Append("Nathan")
        self.listBox1.Append("Jerry")
        self.listBox1.Append("Lamar")
        self.SetTitle("Select a name ...")
        #event.Skip()
 
    def OnButton2Button(self, event):
        '''
        put the ListBox items into a Python list, sort and reload
        '''
        # GetItems() new in wxPython2.8
        name_list = self.listBox1.GetItems()
        name_list.sort()
        # Set() clears and reloads
        self.listBox1.Set(name_list)
        #event.Skip()
 
    def OnButton3Button(self, event):
        '''
        click button to clear the ListBox items
        '''
        self.listBox1.Clear()
        #event.Skip()
 
    def OnListBox1Listbox(self, event):
        '''
        click ListBox item and display the selected string in the frame title
        '''
        selName = self.listBox1.GetStringSelection()
        self.SetTitle(selName)
        #event.Skip()
 
 
# added by BOA via Edit/Add Module Runner
if __name__ == '__main__':
    app = wx.PySimpleApp()
    frame = create(None)
    frame.Show()
    app.MainLoop()

# bouncing a ball of the walls using VPython
# press the right mouse button to drag/rotate the whole thing
# experiments with visual Python from vpython.org
 
import visual as vs
 
# create a red ball
ball_radius = 0.7
ball = vs.sphere(pos=(-5, 0, 0), radius=ball_radius, color=vs.color.red)
# create 2 green opposing walls
wall_right = vs.box(pos=(6, 0, 0), size=(0.2, 4, 4), color=vs.color.green)
wall_left = vs.box(pos=(-6, 0, 0), size=(0.2, 4, 4), color=vs.color.green)
 
# size movement of the ball
dt = 0.05
ball.velocity = vs.vector(2,0,0)
 
# loop it to create the animation
while True:
    # time the moving ball, higher value gives faster speed
    vs.rate(50)
    ball.pos = ball.pos + ball.velocity * dt
    # the ball needs to bounce as it touches the wall
    if ball.x > wall_right.x - ball_radius:
        ball.velocity.x = -ball.velocity.x
    if ball.x < wall_left.x + ball_radius:
        ball.velocity.x = -ball.velocity.x

# ShelveData1.py
# create and initialize a class/structure and save the data to
# a shelve byte stream file that behaves like a dictionary
 
import shelve
 
# a Python class to mimic a C structure or Pascal record
class Person(object):
    """__init__() functions as the class constructor"""
    def __init__(self, name=None, sex=None, slogan=None):
        self.name = name
        self.sex = sex
        self.slogan = slogan
 
    def __getattr__(self, attr):
        """allow for additional (derived) attributes"""
        if attr == 'firstname':
            # assumes name = "first last", slice to the first space
            return self.name[0:self.name.find(" ")]
        else:
            raise AttributeError
 
 
# initialize and load the class (structure) like this ...
emma = Person("Emma Porke", "female", "Vote for Bush and Dick")
jack = Person("Jack Schidd", "male", "Never give a schidd!")
 
# ... or like this (looks more like C) ...
arnie = Person()
arnie.name = "Arnold Negerschwarz"
arnie.sex  = "often"
arnie.slogan = "I know how to spell nukilar!"
 
# this will open or create a shelve file called 'Slogan.SLV'
dbs1 = shelve.open('Slogan.SLV')
 
# note that a shelve file behaves like a {obj.name:object} dictionary
for obj in (arnie, emma, jack):
    # creating the dictionary will automatically save the data to file
    # for each pair key is the objects name and the value is the object
    dbs1[obj.name] = obj
 
# let's add one more ...
frank = Person("Frank Palermo", "male", "An innuendo is a suppository")
# again, this will automatically save the data to file
dbs1[frank.name] = frank
 
print "Saved all data to shelve file 'Slogan.SLV'"
 
# done adding any additional data, close the file (optional, but a good habit)
dbs1.close()

# ShelveData2.py
# load the shelve file 'Slogan.SLV' that was created in ShelveData1.py
 
import shelve
 
# you need the same class you used for writing the shelve data, but
# you can add additional attributes derived from the initial attributes
class Person(object):
    """__init__() functions as the class constructor"""
    def __init__(self, name=None, sex=None, slogan=None):
        self.name = name
        self.sex = sex
        self.slogan = slogan
 
    def __getattr__(self, attr):
        """allow for additional (derived) attributes"""
        if attr == 'firstname':
            # assumes name = "first last", slice to the first space
            return self.name[0:self.name.find(" ")]
        elif attr == 'lastname':
            # assumes name = "first last", slice from the first space
            return self.name[self.name.find(" ")+1:]
        elif attr == 'title':
            # automagically creates a title for the person
            if self.sex == 'male':
                return "Mister"
            elif self.sex == 'female':
                return "Miss"
            else:
                return "Rep."
        else:
            raise AttributeError
 
 
# open the previously created shelve data file
dbs2 = shelve.open('Slogan.SLV')
 
# test it, remember that shelve data work like a dictionary
# these are the keys (the objects names)
print dbs2.keys()            # ['Jack Schidd', 'Arnold Negerschwarz', 'Emma Porke']
 
# to access data you can use
print "Emma's slogan:", dbs2['Emma Porke'].slogan
 
# or simply reestablish objects emma, jack, arnie and frank
emma = dbs2['Emma Porke']
jack = dbs2['Jack Schidd']
arnie = dbs2['Arnold Negerschwarz']
frank = dbs2['Frank Palermo']
 
print
 
print "Just objects emma and jack:"
print '%s says "%s"' % (emma.name, emma.slogan)
print '%s says "%s"' % (jack.name, jack.slogan)
 
print
 
# show it the Pythonian way (good for large person lists) ...
print "The whole list of names (the Pythonian way):"
personList = [emma, jack, arnie, frank]
for pers in personList:
    #print '%s says "%s"' % (getattr(pers, "name"), getattr(pers, "slogan"))
    # simpler ...
    print '%s says "%s"' % (pers.name, pers.slogan)
 
print
 
# this works without establishing objects like emma, jack and arnie ...
# the order will be the dictionary's key order
print "The whole list (the generic way):"
for key in dbs2.keys():
    exec("x = dbs2[key]")
    print '%s %s says "%s"' % (x.title, x.lastname, x.slogan)
 
print
 
# or you can search selected data ...
print "A search of selected data:"
for key in dbs2.keys():
    exec("x = dbs2[key]")
    if x.firstname == "Arnold":
       print '%s says "%s"' % (x.firstname, x.slogan)
    if x.lastname == "Porke":
       print '%s %s says "%s"' % (x.title, x.name, x.slogan)
 
# any changes you make to the dictionary will be
# automatically saved to file, let's try this
jack.slogan = "No more schidd!"
 
print
 
# test it ...
print "Modified data:"
personList = [emma, jack, arnie, frank]
for pers in personList:
    print '%s says "%s"' % (pers.firstname, pers.slogan)