Recently, I was reading about some sample interview questions used (at some point) by Google. One such question was "what are the first 10 consecutive digits of e that form a prime number?" Curious, I went to Wikipedia and looked up some primality tests that I could run on 10-digit prime candidates (if you'll forgive the pun) from e. One such test was Fermat's Primality Test, which can be used to probabilistically assess a number's primality (it fails on Carmichael numbers, et alia). I've written up a short python script which runs the test on the numbers 1 to 100 using computed probable primes as possible coprimes and returns all probable primes.
def test(end): candidates = range(1,end+1) primes = list() for candidate in candidates: prime = True for prime in primes: if candidate % prime: test_result = ((prime ** (candidate - 1)) % candidate) print "Candidate: %s, Prime: %s, Result:%s" %(candidate,prime,test_result) if test_result != 1: prime = False break if prime: primes.append(candidate) return primes test(100)
A friend of mine was talking to me recently about how she wished iTunes let her edit song metadata more easily, as if she were editing a spreadsheet in Excel or OpenOffice. Drawing on this as inspiration, I've written a little python script that gets all music files (as specified in the list file_types) from a folder (and all subfolders), exports their metadata to a Comma Separated Value file, and then takes all changes made to that file and applies them to the tracks. As with my xml playlist downloader, you'll need the ID3 library for python installed.
import fnmatch import os import Tkinter import tkFileDialog import ID3 from tkMessageBox import showinfo root = Tkinter.Tk() root.withdraw() folder = tkFileDialog.askdirectory(title="Please select a music directory.") matches =  file_types = ['mp3','aiff'] for root, dirnames, filenames in os.walk(folder): for filename in reduce((lambda x,y: x + y), [fnmatch.filter(filenames, ('*.' + filetype)) for filetype in file_types]): matches.append(os.path.join(root, filename)) output = 'Title,Artist,Album,Track,Year,File Location (Do Not Alter)\n' for song in matches: line = '' id3info = ID3.ID3(song) columns = [id3info.title,id3info.artist,id3info.album,id3info.track,id3info.year,song] for column in columns: line += '"' + str(column) + '",' line = line[:-1] + '\n' output += line filename = tkFileDialog.asksaveasfilename(defaultextension='.csv',filetypes=[('All Files','.*'),('Comma Separated Values File','.csv')]) f = open(filename,'w') f.write(output) f.close() showinfo("File Created","Your CSV file has been created and is ready for you to edit. After you have done so and saved, please click 'OK'.") f = open(filename,'r') f.readline() #Removing column titles for line in f.readlines(): line.replace('"','') columns = line.split(',')#0:title,1:artist,2:album,3:track,4:year,5:location id3info = ID3.ID3(columns) id3info['TITLE'] = columns id3info['ARTIST'] = columns id3info['ALBUM'] = columns id3info['TRACKNUMBER'] = columns id3info['YEAR'] = columns f.close() showinfo("Success","Song metadata has been successfully updated.")Tags: code, csv, metadata, mp3, music, programming, python, tagging, tkinter
Here's a little something I wrote up to download and tag a bunch of mp3s (of the Christmas song variety) from a jwplayer xml playlist. If you'd like to download from other playlists, simply change xml_url (and perhaps localdir, if you'd like to download your music to somewhere a little more accessible). You'll need to have this ID3 library installed.
import urllib import urllib2 import os import ID3 xml_url = "http://pinochan.net/overbooru/xmas/playlist.xml" localdir = "C:\\Xmas_Music" webdir = xml_url[::-1][xml_url[::-1].find('/'):][::-1] try: os.chdir(localdir) print "Downloading to", localdir except: os.mkdir(localdir) print "Creating download directory", localdir try: xml_page = urllib2.urlopen(xml_url) except: print "Error opening playlist URL." raw_input() quit() print "Parsing XML" xml = xml_page.read().replace("\t","").replace("\n","") tracks = xml.split('Tags: code, jwplayer, metadata, mp3, music, programming, python, tagging, xmas, xml
If you're like me and use the excellent tool over at Color Scheme Designer in conjunction with Paint.Net, you may have grown frustrated with creating palettes one color at a time by copy-pasting hex values. No longer! Below, please find a short python application I wrote (which even uses a fancy and unnecessary GUI) to create Paint.Net palettes from Color Scheme Designer palettes. Just export your Color Scheme Designer palette to text, copy what the site gives you, paste it into the application, and click "convert and save". The resulting file is ready to import into Paint.Net at your leisure.
from Tkinter import * from tkFileDialog import asksaveasfilename as save from tkMessageBox import showinfo as disp def convert(): intext = str(text.dump(1.0, END)) intext = intext.split(' = ') colorlist = list() for ss in intext: if ss == '#': colorlist.append(ss[1:]) filename = save(defaultextension='txt',initialdir='\%HOMEPATH\%\\My Documents\\Paint.NET User Files\\Palettes') palette = open(filename, 'w') for color in colorlist: palette.write('FF%s\n' %color) palette.close() disp('File Saved', 'File successfully saved as %s.' %filename) root = Tk() menubar = Menu(root) menubar.add_command(label="Convert and Save", command=convert) menubar.add_command(label="Quit", command=quit) root.config(menu=menubar) scroll = Scrollbar(root) scroll.pack(side=RIGHT, fill=Y) text = Text(root, wrap=WORD, yscrollcommand=scroll.set) text.pack() scroll.config(command=text.yview) root.mainloop()Tags: code, color, design, internet, programming, python, tkinter, web, web design