Ok - here's how to do karaoke to your favourite video track, and publish the results on your blog
First, you need to get the video. Youtube will have it, guaranteed. There's a neat little linux package you can install to download youtube videos:
$ sudo apt-get install youtube-dl
Then go to youtube, and find the url. I chose 'people everyday' by arrested development - an oldy, but a classic, and its something I knew the words to. Then get it:
$ youtube-dl http://uk.youtube.com/watch?v=r9OjoPskf_c
It will download a 'flv' (flash) format video called the last part of the url - in this case 'r9OjoPskf_c.flv'
This next part isn't strictly necessary, but for ease of future access you may want to rename it, and also get it into some format understood by pretty much everything, e.g:
$ ffmpeg -i r9OjoPskf_c.flv people_everyday.avi
Then you need to record your soundtrack. I found the easiest way to do this was to use a linux tool called 'sound recorder'. Applications - Sound/Video - Sound Recorder. just open a new file and press record - simple!
Oh, but its a good idea to open your video exactly when you press 'record' - to get background and timings
Then when you finish press 'stop'. save it - e.g. 'people_everyday.mp3'
Then use mencoder to mux the mp3 and avi file together, like so:
$ mencoder people_everyday.avi -o output.avi -ovc copy -oac copy -audiofile people_everyday.mp3
Your output file 'output.avi' is ready to go onto your blog - like so!
Happy thanksgiving!
Wednesday, 26 November 2008
Sunday, 23 November 2008
Fourier transform of an identity matrix
... and how to get your matlab plots into animated gifs, and into your blog!
I noted the other day that the fast fourier transform of an identity matrix can look really cool when plotted, and that stringing matrices of increasing size along in an animation looked really cool.
So when it came to sharing it this morning I came across a little fault in blogger which means that you can't directly load animated .gif files into your blog posts. The solution is to upload your image onto the web, get the html for the link, and embed that into your blog post. I used Tinypic - uploaded the image, and embedded the html code here:
Here's the matlab code for the animation
>> cf=0; %current frame
>> for k=10:50 % identity matrix from [10,10] to [50,50]
>> clf;
>> plot(fft(eye(k))) %plot
>> axis equal; axis off; axis([-1 1 -1 1]); % sort out axes
>> pause(0.01) %take a break
>> cf=cf+1; %update current frame
>> saveas(gcf, sprintf('frame%d', 1000+cf), 'jpg') %save the current frame as a jpg
>> end
This next bit of code tells the operating system (the bang command, !) to use the unix program 'convert' to make an animated gif out of all of those frames (i've set it to compress and downsize by half to save on file space)
>> !convert -antialias -loop 1000 -delay 5 -geometry 50% -compress LZW frame10* ffteye.gif
Gif creation is my new favourite toy - watch out Daily Daniel!
I noted the other day that the fast fourier transform of an identity matrix can look really cool when plotted, and that stringing matrices of increasing size along in an animation looked really cool.
So when it came to sharing it this morning I came across a little fault in blogger which means that you can't directly load animated .gif files into your blog posts. The solution is to upload your image onto the web, get the html for the link, and embed that into your blog post. I used Tinypic - uploaded the image, and embedded the html code here:
Here's the matlab code for the animation
>> cf=0; %current frame
>> for k=10:50 % identity matrix from [10,10] to [50,50]
>> clf;
>> plot(fft(eye(k))) %plot
>> axis equal; axis off; axis([-1 1 -1 1]); % sort out axes
>> pause(0.01) %take a break
>> cf=cf+1; %update current frame
>> saveas(gcf, sprintf('frame%d', 1000+cf), 'jpg') %save the current frame as a jpg
>> end
This next bit of code tells the operating system (the bang command, !) to use the unix program 'convert' to make an animated gif out of all of those frames (i've set it to compress and downsize by half to save on file space)
>> !convert -antialias -loop 1000 -delay 5 -geometry 50% -compress LZW frame10* ffteye.gif
Gif creation is my new favourite toy - watch out Daily Daniel!
Saturday, 15 November 2008
Welcome
Welcome to my new site, the Zesty Blogisty. It is a companion site to my main blog, The Daily Daniel
Zesty is intended for my ramblings on operating systems, computer programming, and other geeky stuff that takes my fancy. It's designed not to clog up the 'Daniel with rubbish I want to get off my chest but no-one wants to read!
So I've moved some posts from the 'Daniel to the Zesty and, like joey ramone once said, hey ho, let's go!
Zesty is intended for my ramblings on operating systems, computer programming, and other geeky stuff that takes my fancy. It's designed not to clog up the 'Daniel with rubbish I want to get off my chest but no-one wants to read!
So I've moved some posts from the 'Daniel to the Zesty and, like joey ramone once said, hey ho, let's go!
The ups and downs of skyping with Linux
Originally posted in The Daily Daniel
----------------------------------------
Having recently moved to the USA, my need to communicate cheaply with people back home has meant that I have subscribed to Skype which allows me to call people through computers for free, or to landline or mobile phones at discounted rate.
I use linux because my computer is my toy and, in many respects, my livelihood. Linux is a much more fun and much more powerful operating system because it grants you, at least in principle, more control over the operation of your computer (which is usually unseen and unreachable on windows systems) through commands made in a terminal. Scientific computing is easier and much wider in scope if you know a few basic linux commands. Almost everything in linux is obfuscating, but learning its ways is enormously satisfying. All linux computing is completely free, as it should be.
Being a linux user, however, means that new software like skype are either generally unavailable because they are proprietary, or because the software developers don't choose to make them available to linux users because they represent a small fraction of computer users. Not only was I very glad to hear, then, that skype was available for linux, but that it even dealt with my 64-bit architecture (which has given me all sorts of problems installing drivers and other software, but I won't go into that ...). So I installed skype with no problems:
$ sudo su | sudo apt-get install skype
And it worked fine. So the next thing I did was buy a webcam. I had one delivered through amazon. None of the cheap ones said they were linux compatible, but i through caution to the wind, and got myself one for 31 dollars.
Of course, it came with a cd with windows drivers, and nothing else. After a couple of hours trawling through the web I sort-of semi installed the drivers for it, using the usual linux user forums. Initially, I couldn't get anything to work properly with it - I tried numerous programs (cheese, camorama, XawTV, MoviePlayer, VLC ...). Eventually I got VLC and camorama do work with it. Don't even ask me how now - i remember just applying my usual tenacity to it, and slamming my monkey fists into the keyboard until i hit the right combination of letters and symbols which would tell the program I had a camera, where it was, and what drivers it needed. It probably looked a little something like this (or equally as hideous)
$ sudo jhas -jh 837afm$^&qeiuhn>>KOUUIG4n we8f-&hcjku8hujbn ok?
Right, so after I wiped the blood of the monitor I turned to skype. Crap - skype for linux ''currently doesn't support webcams'' -aaaargh!!! Ok, fine, I can still call and I can text message? No. Skype for linux "currently doesn't support sms messaging". Great - so I can't even txt message. All windows and mac skype users can txt message. Macs run on a LINUX KERNEL and they can txt message!!! The skype developers obviously just cant be bothered to write the code necessary. Or maybe they think that all linux users only have nerdy friends, who are all messaging each other over the internet because thats where they spent 99% of their lives. Erm, no comment
There's nothing quite like skype thats free and open source. So, I went back to the forums, going on the assumption that it must be possible, and that some wonderful person would have either figured a way to crack into the program and unlock the functionality to txt message, or written a new program to interface with skype and allow it to be able to send text messages.
Unlikely as it sounds, and the reason why I make this post, is because not only someone has, but it works. IT WORKS!!! Ha ha ha ha ha in your face! I know this is sad but I'm so happy with this result - i feel like the little orphan boy born with no opportunities and no hopes, who happens to stray across a wadge of bank notes, unsighted, in the dirty street. They have fallen out of a passing carriage. There's a massive grin across my grubby little urchin face. IThere's another eason for my post - to sing the praises of those geeks who toil for hours writing these impenetrable programs, and upload them onto the web for everyone to use.
Next time you see a computer nerd, give him a little squeeze for me.
Don't get me wrong, the solution isnt perfect. Its a little clunky and temperamental, but its all we have and i found it and it works! Ok, so this is what you do: there are two things to download and install. The first is a program language written in python which allows links to skype to be made, and interfacing from the command line. You download it from here. Downlaod the tarball named 'Skype4Py-1.0.29.0.tar.gz', untar it into a directory somewhere (like your desktop), then in the terminal make that directory your working directory and type:
$ sudo su | python setup.py install
It basically allows you to, within python, talk to the skype program and, if your clever enough, get it to do things for you. I tried to write a couple of rudimentary python scripts to do stuff with it, but it would have basically meant learning a new coding language, which I'm not really prepared to do just to send a few txt messages! Turns out I dont have to because someone called Rafael Laboissiere has already done it. As explained here, you install the 'skysentials' program easily:
$ wget http://alioth.debian.org/~rafael/skype/skysentials_1.0.1-1_all.deb
$ sudo dpkg -i skysentials_1.0.1-1_all.deb
Then, open a konsole (if you havent got konsole type # sudo apt-get update, then #sudo apt-get install konsole) by typing
$ konsole
Then open 2 windows. As superuser, type # skype in one - skype appears, and you sign in as per usual. In the other window, type #skysentials. A gui appears which allows you to send texts via skype, working out the cost automatically. Brilliant!
to skype software developers - is this capability latent within skype for linux, and if so why hasnt it been unlocked for users?
to rafael and the developers of skype4Py - you really are clever and unsung, thank you
and to everyone else, goodnight and happy texting, whatever OS you use ...
----------------------------------------
Having recently moved to the USA, my need to communicate cheaply with people back home has meant that I have subscribed to Skype which allows me to call people through computers for free, or to landline or mobile phones at discounted rate.
I use linux because my computer is my toy and, in many respects, my livelihood. Linux is a much more fun and much more powerful operating system because it grants you, at least in principle, more control over the operation of your computer (which is usually unseen and unreachable on windows systems) through commands made in a terminal. Scientific computing is easier and much wider in scope if you know a few basic linux commands. Almost everything in linux is obfuscating, but learning its ways is enormously satisfying. All linux computing is completely free, as it should be.
Being a linux user, however, means that new software like skype are either generally unavailable because they are proprietary, or because the software developers don't choose to make them available to linux users because they represent a small fraction of computer users. Not only was I very glad to hear, then, that skype was available for linux, but that it even dealt with my 64-bit architecture (which has given me all sorts of problems installing drivers and other software, but I won't go into that ...). So I installed skype with no problems:
$ sudo su | sudo apt-get install skype
And it worked fine. So the next thing I did was buy a webcam. I had one delivered through amazon. None of the cheap ones said they were linux compatible, but i through caution to the wind, and got myself one for 31 dollars.
Of course, it came with a cd with windows drivers, and nothing else. After a couple of hours trawling through the web I sort-of semi installed the drivers for it, using the usual linux user forums. Initially, I couldn't get anything to work properly with it - I tried numerous programs (cheese, camorama, XawTV, MoviePlayer, VLC ...). Eventually I got VLC and camorama do work with it. Don't even ask me how now - i remember just applying my usual tenacity to it, and slamming my monkey fists into the keyboard until i hit the right combination of letters and symbols which would tell the program I had a camera, where it was, and what drivers it needed. It probably looked a little something like this (or equally as hideous)
$ sudo jhas -jh 837afm$^&qeiuhn>>KOUUIG4n we8f-&hcjku8hujbn ok?
Right, so after I wiped the blood of the monitor I turned to skype. Crap - skype for linux ''currently doesn't support webcams'' -aaaargh!!! Ok, fine, I can still call and I can text message? No. Skype for linux "currently doesn't support sms messaging". Great - so I can't even txt message. All windows and mac skype users can txt message. Macs run on a LINUX KERNEL and they can txt message!!! The skype developers obviously just cant be bothered to write the code necessary. Or maybe they think that all linux users only have nerdy friends, who are all messaging each other over the internet because thats where they spent 99% of their lives. Erm, no comment
There's nothing quite like skype thats free and open source. So, I went back to the forums, going on the assumption that it must be possible, and that some wonderful person would have either figured a way to crack into the program and unlock the functionality to txt message, or written a new program to interface with skype and allow it to be able to send text messages.
Unlikely as it sounds, and the reason why I make this post, is because not only someone has, but it works. IT WORKS!!! Ha ha ha ha ha in your face! I know this is sad but I'm so happy with this result - i feel like the little orphan boy born with no opportunities and no hopes, who happens to stray across a wadge of bank notes, unsighted, in the dirty street. They have fallen out of a passing carriage. There's a massive grin across my grubby little urchin face. IThere's another eason for my post - to sing the praises of those geeks who toil for hours writing these impenetrable programs, and upload them onto the web for everyone to use.
Next time you see a computer nerd, give him a little squeeze for me.
Don't get me wrong, the solution isnt perfect. Its a little clunky and temperamental, but its all we have and i found it and it works! Ok, so this is what you do: there are two things to download and install. The first is a program language written in python which allows links to skype to be made, and interfacing from the command line. You download it from here. Downlaod the tarball named 'Skype4Py-1.0.29.0.tar.gz', untar it into a directory somewhere (like your desktop), then in the terminal make that directory your working directory and type:
$ sudo su | python setup.py install
It basically allows you to, within python, talk to the skype program and, if your clever enough, get it to do things for you. I tried to write a couple of rudimentary python scripts to do stuff with it, but it would have basically meant learning a new coding language, which I'm not really prepared to do just to send a few txt messages! Turns out I dont have to because someone called Rafael Laboissiere has already done it. As explained here, you install the 'skysentials' program easily:
$ wget http://alioth.debian.org/~rafael/skype/skysentials_1.0.1-1_all.deb
$ sudo dpkg -i skysentials_1.0.1-1_all.deb
Then, open a konsole (if you havent got konsole type # sudo apt-get update, then #sudo apt-get install konsole) by typing
$ konsole
Then open 2 windows. As superuser, type # skype in one - skype appears, and you sign in as per usual. In the other window, type #skysentials. A gui appears which allows you to send texts via skype, working out the cost automatically. Brilliant!
to skype software developers - is this capability latent within skype for linux, and if so why hasnt it been unlocked for users?
to rafael and the developers of skype4Py - you really are clever and unsung, thank you
and to everyone else, goodnight and happy texting, whatever OS you use ...
in 5 minutes, for free (or 'balanced restored')
Originally posted in The Daily Daniel
--------------------------------------
People have said to me words along the lines of "why do you both with linux? it seems as though all it ever gives you is problems blah blah blah ..." - i don't know, I never listen to the rest. Yes, I do moan about linux a lot, and even in these pages ... well here's just 1 example of some routine thing I wanted to do where linux came to the rescue. I did it in 5 minutes
I had a folder full of pictures, and I wanted to make 2 copies of each - one a fraction of the size (for a thumbnail gallery), and one loads bigger - the images were smaller than the CCD used to capture them, so I knew I couldnt alias them. Right, well there's a linux command which does the job called 'convert'. Quick, really simple to use, e.g.:
>> convert my_image.jpg -resize 200% my_new_image.jpg
Does exactly what it says on the quick drying woodstain. But how to do the whole folder in one go? My old friend matlab comes to the rescue, and my personal favourite command 'system' - this bit of code will read in a folder of images, create 2 new folders, copy and resize each image, save it in the correct folder and append the file name with the operation done to it. All in the time it takes you to sneeze.
% find all the jpegs in the folder
>> direc=dir([pwd,filesep,'*.','jpeg']);
% create an empty cell to stick them in
>> filenames={};
% deal inputs into outputs
>> [filenames{1:length(direc),1}] = deal(direc.name);
% sort them and turn them into character arrays
>> filenames=sortrows(char(filenames{:}));
% make 2 directories - one called 'james_and_the_giant_peach' and one called 'thumblina'
>> mkdir([pwd,filesep,'james_and_the_giant_peach'])
>> mkdir([pwd,filesep,'thumblina'])
% simple loop
>> for i=1:size(filenames,1)
% giant images (500% size)
>> system(['convert ',deblank(filenames(i,:))...
,' -resize 500% ./james_and_the_giant_peach/',deblank(filenames(i,:)),'_giant.jpeg'])
% thumbnail images (20% size)
>> system(['convert ',deblank(filenames(i,:))...
,' -resize 20% ./thumblina/',deblank(filenames(i,:)),'_thumb.jpeg'])
>> end
Another example where matlab and linux combine beautifully. Matlab would have done it on its own (using imresize and imwrite commands), but it would have taken considerably longer.
Today is Boomtime. Good night
--------------------------------------
People have said to me words along the lines of "why do you both with linux? it seems as though all it ever gives you is problems blah blah blah ..." - i don't know, I never listen to the rest. Yes, I do moan about linux a lot, and even in these pages ... well here's just 1 example of some routine thing I wanted to do where linux came to the rescue. I did it in 5 minutes
I had a folder full of pictures, and I wanted to make 2 copies of each - one a fraction of the size (for a thumbnail gallery), and one loads bigger - the images were smaller than the CCD used to capture them, so I knew I couldnt alias them. Right, well there's a linux command which does the job called 'convert'. Quick, really simple to use, e.g.:
>> convert my_image.jpg -resize 200% my_new_image.jpg
Does exactly what it says on the quick drying woodstain. But how to do the whole folder in one go? My old friend matlab comes to the rescue, and my personal favourite command 'system' - this bit of code will read in a folder of images, create 2 new folders, copy and resize each image, save it in the correct folder and append the file name with the operation done to it. All in the time it takes you to sneeze.
% find all the jpegs in the folder
>> direc=dir([pwd,filesep,'*.','jpeg']);
% create an empty cell to stick them in
>> filenames={};
% deal inputs into outputs
>> [filenames{1:length(direc),1}] = deal(direc.name);
% sort them and turn them into character arrays
>> filenames=sortrows(char(filenames{:}));
% make 2 directories - one called 'james_and_the_giant_peach' and one called 'thumblina'
>> mkdir([pwd,filesep,'james_and_the_giant_peach'])
>> mkdir([pwd,filesep,'thumblina'])
% simple loop
>> for i=1:size(filenames,1)
% giant images (500% size)
>> system(['convert ',deblank(filenames(i,:))...
,' -resize 500% ./james_and_the_giant_peach/',deblank(filenames(i,:)),'_giant.jpeg'])
% thumbnail images (20% size)
>> system(['convert ',deblank(filenames(i,:))...
,' -resize 20% ./thumblina/',deblank(filenames(i,:)),'_thumb.jpeg'])
>> end
Another example where matlab and linux combine beautifully. Matlab would have done it on its own (using imresize and imwrite commands), but it would have taken considerably longer.
Today is Boomtime. Good night
Dollars and Pounds
Originally posted in The Daily Daniel
-----------------------------------
just for interest
-----------------------------------
just for interest
LaTeX equations in Blogger posts
Originally posted in The Daily Daniel
___________________________
Well, I know you are burning to know this one (!) Fetch the code directly from CodeCogs site and use in your website following this link
It uses beautiful
typesetting to create an image, which you embed in your blog posting. For example, the continuity equation for water waves:
Voila! Hope that's clear
___________________________
Well, I know you are burning to know this one (!) Fetch the code directly from CodeCogs site and use in your website following this link
It uses beautiful
typesetting to create an image, which you embed in your blog posting. For example, the continuity equation for water waves:
Voila! Hope that's clear
A tour through home 'pageranking' - try it yerself!
Originally posted in The Daily Daniel
_____________________________
Now I live in the foothills of silicon valley, I thought I'd write a piece on one of its most famous and useful and revolutionary spawns, Google, and specifically it's PageRank algorithm. This is the piece of code which Google Search engines use to find webpages that are most relevant to your enquiry, and rank them so the most relevant are near the top. Its a bloody marvel, as we all know (remember the bad old days using old lycos and yahoo searches etc - pah!)
Instead of writing stuff on it, which has been done elsewhere numerous times, I thought I would show you how to do it using Matlab
First, you need to get the code. Cleve Moler at Mathworks has written a library which contains a primitive attempt at the proprietary algorithm. You need to get it, unzip it and untar it. This can all be done within Matlab, like so:
>> url='http://www.mathworks.com/moler/ncm.tar.gz';
>> gunzip(url,'ncm')
>> untar('ncm/ncm.tar','ncm')
Next, cd to where you unzipped it to, which is probably -
>> cd([pwd,filesep,'ncm'])
Then run the surfer algorithm on a website of your choosing, this one for example, and tell it to search for n nodes (in this case, 200 - warning, it takes a while)
>> [U,G]=surfer('http://www.thedailydanielblog.blogspot.com',200);
U is a list of websites connected to yours, arranged in matrix G. My website surfer matrix looks a little like this:
I was interested in what these sites were so I wrote a bit of code to print them to a text file:
>> fid=fopen('dansweb.txt','wt');
>> for i=1:size(char(U),1), fprintf(fid,'%s\n',char(U(i,:))); end
>> fclose(fid)
dansweb.txt then contains a list of 200 websites
The pagerank algorithm was then applied to U and G to find
>> pagerank(U,G)
The results are unsurprising - it charts links i have made, blogspot pages associated with my labels, and widgets i have used. There is even a bar chart output:
which looks slightly better if you add the websites to it
page-rank in out url
190 0.0432 9 2 http://www.usgs.gov
191 0.0383 4 2 http://www.usgs.gov/ask
192 0.0383 4 2 http://search.usgs.gov
72 0.0137 21 0 http://www.blogger.com
79 0.0131 40 0 http://purl.org/syndication/thread/1.0
71 0.0129 20 0 http://www.blogger.com/profile/
184 0.0098 5 0 http://planet.ubuntu.com
5 0.0092 60 6 http://www.blogger.com/profile/02981038739002302942
189 0.0092 1 0 http://wiki.octave.org
193 0.0091 6 5 http://marine.usgs.gov
10 0.0087 61 0 http://ims.ucsc.edu
3 0.0086 59 117 http://thedailydanielblog.blogspot.com/feeds/posts/default
4 0.0085 58 118 http://www.blogger.com/feeds/1936258002310927863/posts/default
8 0.0082 57 1 http://www.gnu.org/software/octave
11 0.0082 57 0 http://twitter.com
12 0.0082 57 0 http://hypem.com
63 0.0082 57 7 http://www.ourblogtemplates.com
21 0.0081 56 54 http://thedailydanielblog.blogspot.com/search/label/photos
24 0.0081 56 50 http://thedailydanielblog.blogspot.com/search/label/santa%20cruz
23 0.0081 56 49 http://thedailydanielblog.blogspot.com/search/label/san%20francisco
26 0.0081 56 46 http://thedailydanielblog.blogspot.com/search/label/travel
22 0.0081 56 43 http://thedailydanielblog.blogspot.com/search/label/preparations
25 0.0081 56 42 http://thedailydanielblog.blogspot.com/search/label/santa%20news
14 0.0080 56 36 http://thedailydanielblog.blogspot.com/search/label/internet
15 0.0080 56 36 http://thedailydanielblog.blogspot.com/search/label/job
17 0.0080 56 36 http://thedailydanielblog.blogspot.com/search/label/map
18 0.0080 56 36 http://thedailydanielblog.blogspot.com/search/label/matlab
20 0.0080 56 35 http://thedailydanielblog.blogspot.com/search/label/musings
16 0.0080 56 34 http://thedailydanielblog.blogspot.com/search/label/linux
27 0.0080 56 34 http://thedailydanielblog.blogspot.com/search/label/work
19 0.0080 56 33 http://thedailydanielblog.blogspot.com/search/label/move
6 0.0078 21 0 http://www.blogger.com/openid-server.g
67 0.0069 20 0 http://www.blogger.com/openid-server.g\42 /\76\n
196 0.0057 3 4 http://walrus.wr.usgs.gov/infobank
197 0.0057 3 2 http://mrib.usgs.gov
183 0.0053 4 1 http://fridge.ubuntu.com
194 0.0052 3 0 http://vineyard.er.usgs.gov/query.html
66 0.0052 17 0 http://www.blogger.com/profile/02981038739002302942\42 /\76\n
So, I have a pagerank of 0 (more or less) which is the lowest possible. The highest is 10, so this isn't a great example, admittedly, but I'll let interested readers have a play.
I discovered that facebook has a 9 and plymouth.ac.uk has a 7. Now, before you comment, i know that there are already loads of web-based pagerank checkers out there, but this is more fun, and here you get a breakdown of what sites contribute to each other's scores, OK?
Said in a Neil Buchanon from Art Attack (ITV since the 1990s) - 'try it yerself'!!
>> clear, clc, exit
_____________________________
Now I live in the foothills of silicon valley, I thought I'd write a piece on one of its most famous and useful and revolutionary spawns, Google, and specifically it's PageRank algorithm. This is the piece of code which Google Search engines use to find webpages that are most relevant to your enquiry, and rank them so the most relevant are near the top. Its a bloody marvel, as we all know (remember the bad old days using old lycos and yahoo searches etc - pah!)
Instead of writing stuff on it, which has been done elsewhere numerous times, I thought I would show you how to do it using Matlab
First, you need to get the code. Cleve Moler at Mathworks has written a library which contains a primitive attempt at the proprietary algorithm. You need to get it, unzip it and untar it. This can all be done within Matlab, like so:
>> url='http://www.mathworks.com/moler/ncm.tar.gz';
>> gunzip(url,'ncm')
>> untar('ncm/ncm.tar','ncm')
Next, cd to where you unzipped it to, which is probably -
>> cd([pwd,filesep,'ncm'])
Then run the surfer algorithm on a website of your choosing, this one for example, and tell it to search for n nodes (in this case, 200 - warning, it takes a while)
>> [U,G]=surfer('http://www.thedailydanielblog.blogspot.com',200);
U is a list of websites connected to yours, arranged in matrix G. My website surfer matrix looks a little like this:
I was interested in what these sites were so I wrote a bit of code to print them to a text file:
>> fid=fopen('dansweb.txt','wt');
>> for i=1:size(char(U),1), fprintf(fid,'%s\n',char(U(i,:))); end
>> fclose(fid)
dansweb.txt then contains a list of 200 websites
The pagerank algorithm was then applied to U and G to find
>> pagerank(U,G)
The results are unsurprising - it charts links i have made, blogspot pages associated with my labels, and widgets i have used. There is even a bar chart output:
which looks slightly better if you add the websites to it
page-rank in out url
190 0.0432 9 2 http://www.usgs.gov
191 0.0383 4 2 http://www.usgs.gov/ask
192 0.0383 4 2 http://search.usgs.gov
72 0.0137 21 0 http://www.blogger.com
79 0.0131 40 0 http://purl.org/syndication/thread/1.0
71 0.0129 20 0 http://www.blogger.com/profile/
184 0.0098 5 0 http://planet.ubuntu.com
5 0.0092 60 6 http://www.blogger.com/profile/02981038739002302942
189 0.0092 1 0 http://wiki.octave.org
193 0.0091 6 5 http://marine.usgs.gov
10 0.0087 61 0 http://ims.ucsc.edu
3 0.0086 59 117 http://thedailydanielblog.blogspot.com/feeds/posts/default
4 0.0085 58 118 http://www.blogger.com/feeds/1936258002310927863/posts/default
8 0.0082 57 1 http://www.gnu.org/software/octave
11 0.0082 57 0 http://twitter.com
12 0.0082 57 0 http://hypem.com
63 0.0082 57 7 http://www.ourblogtemplates.com
21 0.0081 56 54 http://thedailydanielblog.blogspot.com/search/label/photos
24 0.0081 56 50 http://thedailydanielblog.blogspot.com/search/label/santa%20cruz
23 0.0081 56 49 http://thedailydanielblog.blogspot.com/search/label/san%20francisco
26 0.0081 56 46 http://thedailydanielblog.blogspot.com/search/label/travel
22 0.0081 56 43 http://thedailydanielblog.blogspot.com/search/label/preparations
25 0.0081 56 42 http://thedailydanielblog.blogspot.com/search/label/santa%20news
14 0.0080 56 36 http://thedailydanielblog.blogspot.com/search/label/internet
15 0.0080 56 36 http://thedailydanielblog.blogspot.com/search/label/job
17 0.0080 56 36 http://thedailydanielblog.blogspot.com/search/label/map
18 0.0080 56 36 http://thedailydanielblog.blogspot.com/search/label/matlab
20 0.0080 56 35 http://thedailydanielblog.blogspot.com/search/label/musings
16 0.0080 56 34 http://thedailydanielblog.blogspot.com/search/label/linux
27 0.0080 56 34 http://thedailydanielblog.blogspot.com/search/label/work
19 0.0080 56 33 http://thedailydanielblog.blogspot.com/search/label/move
6 0.0078 21 0 http://www.blogger.com/openid-server.g
67 0.0069 20 0 http://www.blogger.com/openid-server.g\42 /\76\n
196 0.0057 3 4 http://walrus.wr.usgs.gov/infobank
197 0.0057 3 2 http://mrib.usgs.gov
183 0.0053 4 1 http://fridge.ubuntu.com
194 0.0052 3 0 http://vineyard.er.usgs.gov/query.html
66 0.0052 17 0 http://www.blogger.com/profile/02981038739002302942\42 /\76\n
So, I have a pagerank of 0 (more or less) which is the lowest possible. The highest is 10, so this isn't a great example, admittedly, but I'll let interested readers have a play.
I discovered that facebook has a 9 and plymouth.ac.uk has a 7. Now, before you comment, i know that there are already loads of web-based pagerank checkers out there, but this is more fun, and here you get a breakdown of what sites contribute to each other's scores, OK?
Said in a Neil Buchanon from Art Attack (ITV since the 1990s) - 'try it yerself'!!
>> clear, clc, exit
Geeky things i found
Originally posted on 'The DailyDaniel'
------------------------------------------
Linux is 17 years old. In May 2008, 1.95% of the OS market was shared by Linux distributions (compared to 91.11% Windows). This depresses me.
Check out Ubuntu at http://www.ubuntu.com/. It's just a great operating system.
%%%%%%%%%%%%%%%%%%%
Did you know that the Matlab logo (the first eigenfunction of the L-shaped membrane) is on a “sponsor a highway” sign on Route 9 in Natick,Massachusetts. Cleve Moler, creator of Matlab, likened its shape to "a beach towel blowing in the wind, constrained by a picnic basket on one-fourth of the towel".
%%%%%%%%%%%%%%%%%%
A map of the internet!!! Now this IS cool
http://www.touchgraph.com/TGGoogleBrowser.php?start=digg.com
%%%%%%%%%%%%
and finally a very funny and clever map from the makers of the Onion
http://www.theonion.com/content/atlas/
Good night!
------------------------------------------
Linux is 17 years old. In May 2008, 1.95% of the OS market was shared by Linux distributions (compared to 91.11% Windows). This depresses me.
Check out Ubuntu at http://www.ubuntu.com/. It's just a great operating system.
%%%%%%%%%%%%%%%%%%%
Did you know that the Matlab logo (the first eigenfunction of the L-shaped membrane) is on a “sponsor a highway” sign on Route 9 in Natick,Massachusetts. Cleve Moler, creator of Matlab, likened its shape to "a beach towel blowing in the wind, constrained by a picnic basket on one-fourth of the towel".
%%%%%%%%%%%%%%%%%%
A map of the internet!!! Now this IS cool
http://www.touchgraph.com/TGGoogleBrowser.php?start=digg.com
%%%%%%%%%%%%
and finally a very funny and clever map from the makers of the Onion
http://www.theonion.com/content/atlas/
Good night!
Subscribe to:
Posts (Atom)