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# Community Blogs

## Do Your Friends Know You Tweet?

They'd better because Twitter has become an important new tool in building relationships and getting your message across.  This post details how to get started building your followers and adding value to the Twitter community.

I recently saw survey results from a 60 Minutes/Vanity Fair poll that stated only 15 percent of Americans believe Twitter to be an important new tool for communication and I believe it.  Not because it's true but because Twitter can be hard to understand and get the hang of at first.

I distinctly remember my first experience with Twitter when I noticed someone casually mentioning they were "putting lipstick on at a redlight".  My first thought was "this is totally worthless".  My how times have changed.  Not only has the growth of Twitter been off the charts (1382% to be exact), but I've actually started using Twitter on a regular basis and find it extremely helpful and useful in my job.

Twitter can be tough to understand at first and there's good reason for it; its a different communication model than most are used to.  How ...

## Digital Differential Analyzer (DDA) Algorithm

```/************************************************** Digital Differential Analyzer (DDA) Algorithm *************************************************** Usage    :- Simple and general method for rasterizing lines and triangles* Author   :- Rooparam Choudhary* Date     :- August 29, 2009* Place    :- Shri Mata Vaishno Devi University* EntryNo  :- 2006ECS20*/#include <graphics.h>#include <stdlib.h>#include <stdio.h>#include <iostream>#define ROUND(x) ((int)(x+0.5))int    MYCOLOR = WHITE;inline void setpixel(int, int);void DDA(int, int, int, int);void unionJack(void);void hexagon(int, int);void randomUnionJack(int);inline void setpixel(int x, int y){  putpixel(320+x, 240-y, MYCOLOR);}void randomUnionJack(int count){   void DJ(int, int, int);   int xr, yr, clr=0;   srand(time(NULL));
while(count-- > 0){                 xr = -320 + rand()d1;                 yr = -240 + rand()H1;                 clr = 0;                 if(yr > -xr){                       if(xr < 0)        clr = 3;                       else if(yr < 0)   clr = 2;                       else if(yr > xr)  clr = 4;                       else if(yr < xr)  clr = 1;                 }else if(yr < -xr) {                       if(xr > 0)        clr = 3;                       else if(yr > 0)   clr = 2;                       else if(yr < xr)  clr = 4;                       else if(yr > xr)  clr = 1;                 }                 DJ(xr, yr, clr);   }}void DJ(int x, int y, int clr){   int shade = 0;   switch(clr){   case 1:     shade = RED;        break;   case 2:     shade = BLUE;       break;   case 3:     shade = CYAN;       break;   case 4:     shade = MAGENTA;    break;   default:    return;             break;   }   putpixel(320+x, 240-y, shade);}void DDA(int x0, int y0, int x1, int y1) {  int delX = x1-x0, delY = y1-y0, steps, k;  float x=x0, y=y0, incX, incY;  steps = (abs(delX) > abs(delY)) ? abs(delX) : abs(delY) ;  incX = delX / (float)steps;  incY = delY / (float)steps;  setpixel(ROUND(x), ROUND(y));  for(k=0; k<steps; ++k) {      x += incX;      y += incY;      setpixel(ROUND(x), ROUND(y));  }}int main(void) {  int gd = DETECT, gm;  char *author = "Coder:- Rooparam Choudhary";  char *algo = "Digital Differential Analyzer Algorithm";  char point[30];  std::cout << "Digital Differential Analyzer Algorithm
";  std::cout << author << std::endl;  initgraph(&gd, &gm, "C:");  setcolor(WHITE);  setbkcolor(GREEN);  outtextxy(320 - textwidth(algo)/2, 5, algo);  outtextxy(getmaxx()-4 -textwidth(author), getmaxy()-20, author);  setcolor(GREEN);  setbkcolor(BLACK);  MYCOLOR = GREEN;  // X-axis  DDA(-320, -1, 320, -1);  DDA(-320,  0, 320,  0);  DDA(-320,  1, 320,  1);  // Y-axis  DDA(-1, 240, -1, -240);  DDA( 0, 240,  0, -240);  DDA( 1, 240,  1, -240);  // Y - X = 0  DDA(-240, -240, 240, 240);  // Y + X = 0  DDA(-240, 240, 240, -240);  MYCOLOR = BROWN;  hexagon(-160, 120);  hexagon(160, 120);  hexagon(160, -120);  hexagon(-160, -120);  std::cout << "Enter samples for union jack
(SHOULD BE GEATER THAN 100K): ";  int samp;  std::cin >> samp;  //unionJack();  randomUnionJack(samp);  setcolor(WHITE);  setbkcolor(GREEN);  outtextxy(320 - textwidth(algo)/2, 5, algo);  outtextxy(getmaxx()-4 -textwidth(author), getmaxy()-20, author);  setcolor(GREEN);  setbkcolor(BLACK);  int x0, y0, x1, y1;  MYCOLOR = WHITE;  std::cout << "Enter '-400' to exit
";  std::cout << "Enter the coordinates of end points: [x0 y0 x1 y1]
";  std::cin >> x0;  while(x0 != -400) {      std::cin >> y0 >> x1 >> y1;      sprintf(point, "(M, M)", x0, y0);      outtextxy(320+x0-textwidth(point)/2, 240-y0+2, point);      sprintf(point, "(M, M)", x1, y1);      outtextxy(320+x1-textwidth(point)/2, 240-y1+2, point);      DDA(x0, y0, x1, y1);      setcolor(WHITE);      setbkcolor(GREEN);      outtextxy(320 - textwidth(algo)/2, 5, algo);      outtextxy(getmaxx()-4 -textwidth(author), getmaxy()-20, author);      setcolor(GREEN);      setbkcolor(BLACK);      std::cin >> x0;  }  closegraph();  return 0;}void unionJack(void){  for(int y = 240; y>0; --y) {          int x = -321;          MYCOLOR = BLUE;          while(++x < -y)              { putpixel(320+x, 240-y, MYCOLOR); }          MYCOLOR = CYAN;          while(++x < 0)              { putpixel(320+x, 240-y, MYCOLOR); }
MYCOLOR = MAGENTA;          while(++x < y)              { putpixel(320+x, 240-y, MYCOLOR); }          MYCOLOR = RED;          while(++x < 321)              { putpixel(320+x, 240-y, MYCOLOR); }  }  for(int y = -1; y>-241; --y) {          int x = -321;          MYCOLOR = RED;          while(++x < y)              { putpixel(320+x, 240-y, MYCOLOR); }          MYCOLOR = MAGENTA;          while(++x < 0)              { putpixel(320+x, 240-y, MYCOLOR); }          MYCOLOR = CYAN;          while(++x < -y)              { putpixel(320+x, 240-y, MYCOLOR); }          MYCOLOR = BLUE;          while(++x < 321)              { putpixel(320+x, 240-y, MYCOLOR); }  }}void hexagon(int xc, int yc) {  DDA(xc+60, yc+104, xc+120, yc);  DDA(xc+60, yc+104, xc+60, yc-104);  DDA(xc+60, yc+104, xc-60, yc-104);  DDA(xc+60, yc+104, xc-120, yc);  DDA(xc+60, yc+104, xc-60, yc+104);  DDA(xc+120, yc, xc+60, yc-104);  DDA(xc+120, yc, xc-60, yc-104);  DDA(xc+120, yc, xc-120, yc);  DDA(xc+120, yc, xc-60, yc+104);  DDA(xc+60, yc-104, xc-60, yc-104);  DDA(xc+60, yc-104, xc-120, yc);  DDA(xc+60, yc-104, xc-60, yc+104);  DDA(xc-60, yc-104, xc-120, yc);  DDA(xc-60, yc-104, xc-60, yc+104);  DDA(xc-120, yc, xc-60, yc+104);}```

## I am back!

There were a lot of things going on in my life, but everything seems to settle down.

## the first

wow wow wow!

this is my first time to write blog with English. actually,my first language is not English. so i have to use many time to learn English.

Also i learn computer by myself.Just for fun!

AND this is my really first time to use Linux(it seems that i have said it several days before!).i love Linux ,i love Ubuntu .In fact , i had tried fedora9 in my old machine last year.But it's nightmare for me .THE machine has 224RAM,AMD Sempron3000+.

Try it!Do it!

## Automation security and OOPs!

Quick note for all.  I just learned that if you start a blog, get a call from Nagios that a raid array crashed, and mark a blog you just started as "unpublish" it just might get published auto magically for you at some point in the future.

For those who read that piece of a blog, sorry.  I'll edit locally and cut and paste going forward. As one gentleman I know once said, "Whatever automation and security do for you they also do to you."  Well it did it to me this time.

Ich möchte euch hier das Firefox-Addon "Ubiquity" vorstellen. Mir war das Addon bis heute nicht bekannt...es scheint aber eines der besten Addons zu sein, das ich bisher gesehen habe. Ubiquity bietet eine Art Schnittstelle zu Online-Inhalten, wie Suchmaschinen oder anderen Diensten. Über die Tastenkombination STRG + Space (kann man auch frei wählen) ruft man Ubiquity in den Vordergrund (Bild 1), welches dann in der linken oberen Ecke des Browsers erscheint. Hier hat man nun die Möglichkeit, über ein Eingabefeld bestimmte Befehle einzugeben und gewünschte Dienste, etc... aufzurufen.
Beispiele:
Browser-Kommandos wie "exit firefox", "restart firefox", "close window", "close tab", "fullscreen" und vielen weiteren
E-Mail schreiben (momentan nur GMail): Eingabe "gmail + Nachricht + to Empfänger" (Bild 3) E-Mails abrufen: Eingabe "get last mail"
Google Maps: Eingabe "map + Ort" (Bild 4)
Youtube: Eingabe "youtube + Suchbegriff".....genauso funktioniert das mit Flickr, Wikipedia, Yahoo, Digg, Amazon, Ebay und vielen anderen Diensten.
Wetter: Eingabe "get weather + Ort"
Twitter: Eingabe "tweet + Nachricht + as Benutzername"
Regional ganz interessant für den VRR (Verkehrsverbund Rhein-Ruhr) eine Fahrplanauskunft: Eingabe "vrr + from Ort + to Ort"
Ich könnte diese Liste nun endlos erweitern. Ubiquity macht das Surfen im Netz jedenfalls deutlich einfacher und schneller.
Screenshots:
Bild 1

Bild 2

Bild 3

Bild 4

Hier gibt es die aktuelle stabile Version. Eine Preview-Version findet ihr hier:
Mozilla Labs Ubiquity (Einfach auf "latest Beta" klicken)
Weitere Erklärung mit kurzem Video:
Der Browser versteht mich & Add-ons ohne Neustart - Firefox 3.6, 4.0 und mehr: Die Zukunft des Mozilla-Browsers - CHIP Online

## My first time in Linuz.com

This is something cool.

I can have my own blog here... does this make me a Linux Expert?

I know, that everybody of visitors can tell nearly the same story about their way to GNULinux. However, it seems to me, that such kind of story is significally important for people who are not sure about moving to GNULinux. So, I'll try to tell about my story.

Everything started more than year ago, when I was going throw the local computer shop, I SUDDENLY saw IT - Linux Format magazine. It was a great thing, main subject was GNOME vs KDE. Such a holy war was interesting for me, but there was one small problem - I hadn't known anything about Linux. ANYTHING!

So, I had bought Linux Format, came home and started to read it. There was a great interview with Richard Stallman, but for me the most surrising thing was his appearence, especially beard. With the help of spirit from this interview I started to install my first GNULinux - Mandriva 2008.0. Of course, there were no problems, except small one - I destroyed all my data from Windows partition.Β¬β

After installation I tried to setup my VPN internet communication. I failed. I reinstalled the distribution. And failed again. So i spent whole my weekend reinstalling the distribution. When I was about to install Windows back, my friend (who is fan of Apple) advised me to use his MacBook for searching solution in th Web. After several hours of searching, I finally found instruction and started to explore the console in Mandriva. Suprisingly, console was quite sex appealing for me, so I decided to try another distribution - I chose... Arch.

Oh, that was great - I spent whole night reading manuals, so I got up at 11 o'clock and found myself lying on the keyboard with KDEmod launched on my screen

## Linux just Works

Dual-booting should never be this hard. But for some reason Microsoft's ode to crappy names, and crappy OS design and development seems to love to make things harder than they have to be. I've had some serious issue with Vista ever since I bought the OS under the assumptions that it would be nearly as friendly, and refreshing as XP. If it wasn't for Vista I could even come to the conclusion that perhaps I would have never tried Ubuntu, and thus any other linux distribution out there. So as of tonight I'd like to outline a few ways in which crappy OS' like Vista make me delighted to be a penguin.

I began my installation of Vista as I normally do with dual-booting, apprehensive. I setup my second drive as NTFS and slipped the Vista disk in. Installation went smoothly, and setting up grub to be my primary bootloader went smoother than normal. Much smoother than it ever had in the past thanks to great help at ubuntuforums.com.

But this was short-lived. After the installation I was left with the usual myriad of issues that needed immediate fixing. This included getting my Audigy 2 ZS to work under Vista (mostly a Creative issue), downloading and installing drivers for a 9500 GT and a Linksys wireless adaptor, downloading updates, and then maybe I could get to what I installed the OS in the first place for, in this case playing pc games.

Things went well until after I downloaded Fallout 3 and attempted to extract it. Vista would give me errors that it could not extract a 5.5Gb archive into roughly 50Gb of hard drive space. Explorer was having a problem with this, and I couldn't get a straight answer anywhere online. It was around this time that the updates finished downloading, and I was prompted to restart. Strangely some updates did not download. No issue, I hoped.

Upon restart the updates were configured, for nearly an hour. Vista then restarted itself and gave me an error, so I had to place the install disc back into the drive to run repair. This appeared to fix the issue until halfway to downloading Winzip, in an attempt to rectify the previous issue, I was greated with the great spirit of Windows, the Blue Screen of Death. Wonderful, I thought to myself, not even 5 hours into Vista's lifespan it is already having issues with itself. A forced restart later, and another attempt at running the OS proved that the BSOD didn't plan on going away. So here I am, reinstalling a version of Windows not 5 hours old.

As you can tell, getting Vista just to run successfully is a huge trial in patience. When Ubuntu performs every needed task faster, stabler, and more securely it boggles my mind that Microsoft has gotten away with the crap they put on store shelves. And if those of you who are interested in Windows 7 think that things may change, think again, I received concurrent BSOD's in that OS as well. My Windows 7 install disk now sits happily at the bottom of a landfill somewhere in New Mexico.

It is a huge burden to setup Vista when every Linux distribution I've used has done things better than Vista out-of-the-box, so to speak. Just staring at the installation screen makes me sigh not knowing what issue it will throw at me next. And realizing this I'll probably just end up formatting the drive again, and turning on Ubuntu to get things done. And slowly I realize why I switched to Linux in the first place, and take a quiet resignation and joy in the fact that Linux just works.

## Halfway status report. Display - success

My computer is becoming wearable, though it's taking some time.

Half of the allocated time is gone already, and I feel like I should have accomplished a lot more. Also I feel like I'll be finished in a week, which is not true either. I now have a working computer, which doesn't yet seem to understand my 3g, working head mounted display, in monochrome as it's a lot more readable that way and I'm going to spend my time in command line anyway, and barebones keyboard, which has not yet been programmed because of missing atmega8 programmerthingy.

My achievement this week has definitely been the display. I have bought a lot of cables and adapters. The Beagleboard gives S-video and Myvu Crystal wants S-video or composite, but it accepts a 4 conductor 3.5mm plug. Currently I have a modified S-video to RCA -> RCA to 3.5mm plug, but a while ago I had like four or five adapters and cables going around. That thing didn't "just work" and everything was a lot better after I had replaced the wiring. I did try to mess with the os settings for overlays, displays and framebuffers without enough knowledge, but the problem was with my cables. There was also the thing that first I didn't get any signal at all before Gregor Richards helped me a bit. There's just so much conflicting and old information, and not enough new information about s-video on Beagleboard+Ångstrom. I'll also have to thank a fellow student who has been helping me with some information and other things.

I still need to modify them though. Myvu Crystal is a weird thing, as the usb-charging cable works as a ground, and so I shouldn't have another ground going to Beagleboard, because that messes the signal up. I already cut the ground pins there, but wasn't enough. Currently I get best signal if I leave those RCA cables hanging so that their grounds don't touch each other and I use the white RCA of the a/v jack and just touch the first metal thing on the Myvu pendant with the tip of the 3.5mm plug. If I use the red one and just stick the 3.5mm plug in, it gets worse signal. Probably because there's also sound signals going there. I need to break the plug so, that there is just the last tip that can connect to anything.

It's been irritating to look at micro sized flashing ntsc screen, but now it is perfectly readable and the signal is just perfect. After I've fixed the cables, I'll just need to break the myvu and put one of the displays inside some sunglasses I'll be buying soon. I'll also need that stupid half-silvered/see-through mirror which will be in front of my eye and which will allow me to see through the display. Then the display is done.

It could have been a lot easier and better, and still might be, if I'd just buy the correct driver chip from Kopin. It's "just" 50\$ and the correct is that version where I could bypass the composite and just feed it a pure digital display (I've been told that myvu pendant has the driver board version that has some stupid chip which you can't see it's pins so no wiring there). That way I could have used the dvi-d signal of Beagleboard and everything would be lollipops and rainbows. They still are, but they would be the colored things that way. There are some nice specifications at Kopin webpage. For your information, Myvu Crystal uses Kopin 640x480 microdisplays. Driver board might, or might not be Kopin, but it has the same chips that handles the signals and probably the same decoder for composite/s-video signals.

I'll be getting the chip for the keyboard (Spiffchorder) soon, but I'll need to rewire the keys and craft a handle for it. I'll try making one from finfoam. Then the keyboard is also done, if it can type scandinavian letters like ö and such. If not, I might need to touch their code too.

My computer needs wvdial or something similar, so it could use my 3g. It also needs a box, maybe from finfoam. Maybe I should make the box from some clear plastic though. I have ordered a usb ethernet card just because I'll probably need it sometimes. I'll need to decipher why narcissus, the awesome Ångstrom distribution image builder gives me enlightenment and gnome-games and such, when I clearly order a command-line only setup. I don't know what I should kill to get to command-line now. Alt+ctrl+F1 doesn't work, though it clearly has worked sometimes for some unfathomable reason. If I just kill enlightenment, xorg and/or gpe-login, they will just restart. I should study my chosen distribution a bit more.

And finally, I'll need a battery. I'm thinking about those rechargable batteries, I've seen some high mah ones that should do with some kind of a 5V regulator.

I'm trying to do most of the keyboard this weekend, then I'll check the software I'll be using and the cables. I need some new, short cables, It's been a joke of the day that I could use them as my only clothing. It also seems that being mobile doesn't mean not having lots of wires around. After my keyboard is finished, I'll build the computer case and the sunglasses-display, and afterwards, I'll make the battery and start wearing the thing when I'll manage to find a way to wear them. Maybe I could just hang the computer from my belt. I definitely don't want a fannypack or a backpack. Maybe something like the Casebelt from Urban tools. Do you know some nice way for wearing the wearable? Comments welcome.

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