import re
import os

#that's it, you can see that the reason for compiling the regex is so you can use m.search as a function pointer which accepts the list of all items in the directory



s = "-this is. A - sentence;one-word what's"
re.findall("\w+-\w+|[\w']+",s)


result: ['this', 'is', 'A', 'sentence', 'one-word', "what's"]

make sure you notice that the correct ordering is to look for hypenated words first!

example:
>>> import re
>>> m = re.compile(r'.{5}|.*',re.S)
>>> data = "HELLO_WORLD_HOW_ARE_YOU"
>>> m.findall(data)
['HELLO', '_WORL', 'D_HOW', '_ARE_', 'YOU']


I would assume that this is the most efficient way to do this, as it uses underlying c functions, and there’s nothing better than zippy python : )


import numpy as np
arr = np.fromstring(buff,dtype=np.uint16).astype(np.uint32)
arr = 0xFF000000 + ((arr & 0xF800) >> 8 ) + ((arr & 0x07E0) << 5) + ((arr & 0x001F) << 19)
return Image.frombuffer('RGBA', (xdim,ydim), arr, 'raw', 'RGBA', 0, 1)


While it may seem like an odd bit shift, stuffing the channels into an int requires that it get stuffed as (most significant bit) ABGR (least significant bit). If you were to use the PIL call to putpixel, it would get stuffed as RGBA.

While I may be a fan of embedded systems, I have to admit that python has become my new love. Thought taking into account that you can do sweet Matlab style dsp with it, you can’t really blame me. Assuming you have raw data from an image, you can do some awesome stuff with it using python. You will of course need python 2.6 as well as the numPy module installed. The techniques I’m going to discuss are already out there if you look for Matlab references but I thought I’d bring to light that you can do the same things using python as well. You will need to go to http://www.pythonware.com/products/pil/ to get the image module. After installing, I will suggest that you compile your entire python directory. To do that, open the python console and type:

import compileall
compileall.compile_dir(‘C:\python26′,force = True,maxlevels=20)

Now,lets start off simple by doing some masking. However, you should first create a 100×100 maroonish jpg in mspaint

Open your python console and type the following

from numpy import *
import Image

#import the jpg
im = Image.open(“test.jpg”)

#split the image into numpy arrays so we can do all kinds of matrix voodoo on it
[r,g,b] = [array(im.split()[i] for i in range(3)]
image = array([r,g,b])

# create a mask and define the region we will want to keep when we mask our image
mask = zeros((13,13),dtype=int) # make a 100×100 integer array of zeros
mask[0:25,0:25] = 0xFF #define the positive mask region noting that RGB has a max value of FF,FF,FF

The upper corner of your image should now be maroon while the rest of your image is white.
test = array[0:3] & mask

I have been a bit busy to comment them but I hope that they may be useful still as just coding examples.

Enjoy

Verilog – 14-bit BCD ( Binary Converted to Decimal)
Verilog – 4 to 1 and 2 to 1 multiplexor
Verilog – Seven Segment Display on Spartan 3 Board
Verilog – Simle PB Debounce Code For Spartan 3 Boards

- comp-e

I on the other hand, appologize for not tossing up any new coding examples.  As of late I’ve been rather busy but fear not for I’ve been dabbling in Python and have some fun stuff to share.  To give a bit of a hint, I’ve been playing with the Numpy module and have found it incredibly useful as it ties in exceptionally well with Matlab.  I also plan on making a mini program to poll USB for those of you who rely on antiquated RS232 and are left without an easy means of switching over : )

Lastly, I encourage more of you to join and contribute well documented examples to the site.  As always, there are no ads and questions will be answered without the arrogant charm of other such code collaborative sites

On the sender side is a simple function written in C that takes a byte and loops through masking each bit.  This masking is done inside an if / else block and the result determines whether or not you are getting a dit or a dash.

Tied to the RF receiver is another MC9S08QG8 which takes in the signal via interrupts and assembles eight interrupts into eight bytes.  It then does a series of bitwise operations on each of the eight bytes in order to reconstruct the original byte.  You will find that a few parts of the code are subject to change (the time for 0′s and 1′s can be adjusted and must be adjusted if you plan on implementing PLL or have a different desired data rate).  That byte is then sent to a PC vie RS232 serial port and stored using a free program called RS232 Data Logger from Eltima Software.  The code will be posted shortly under the microcontroller section on the COMP-E forum for you to use and enjoy.

- COMP-E

~ ALERT: This post does not return to main !!!

-  COMP-E