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Matthieu Parizy
Works at Fujitsu Laboratories LTD
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Matthieu Parizy

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What is a program?

A program is a set of directions, a recipe, that is used to provide an answer to some problem. It usually consists of a set of instructions to be performed or carried out in a certain order. It starts with the given data and parameters as the ingredients, and ends up with a set of answers as the cake. And, as with ordinary cakes, if you make a mistake in your program, you will end up with something else - perhaps hash!

Any program must fulfill two requirements before it can even be carried out. The first is that is must be presented in a language that is understood by the "computer." If the program is a set of instructions for solving linear equations, and the "computer" is a person, the program will be present in some combination of mathematical notation and English. If the person solving the equations is a Frenchman, the program must be in French. If the "computer" is a high speed digital computer, the program must be presented in a language the computer can understand.

The second requirement for programs is that they must be completely and precisely stated. This requirement is crucial when dealing with a computer, which has no ability to infer what you meant - it can act only upon what you actually present to it.

We are of course talking about programs that provide numerical answers to numerical problems. To present a program in the English language, while easy on the programmer, poses great difficulty for the computer because English, or any other spoken language, is rich with ambiguities and redundancies. those quality which make poetry possible but computing impossible. Instead, you present your program in a language that resembles ordinary mathematical notation, which has a simple vocabulary and grammar, and which permits a complete and precise specification of your program.

A manual for BASIC, the elementary algebraic language designed for the Dartmouth Time Sharing System. 1 October 1964. Copyright 1964 by the Trustees of Dartmouth College. Reproduction for non-commercial use is permitted provided due credit is given to Dartmouth College.
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Matthieu Parizy

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Merci et bonne fin de journée.;-)
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How Game of Thrones scenario is written by George R. R. Martin:
http://img.gawkerassets.com/img/18cm3hkxydxbajpg/original.jpg
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So here's the random trick of the day: say you decided to finally upgrade your monitor due to a random discussion on G+, but it turns out that you haven't upgraded your desktop in a while, so you're stuck with single-link DVI.

And the fancy new monitor is a 2560x1440 one that requires dual-link DVI to drive it, so says the documentation in big letters. What do?

Of course, you could just try to find a HDMI cable, since I suspect the machine is still new enough that it happily does HDMI at pixel frequencies high enough that it would all work fine. But you're a lazy git, and you can't find a cable anywhere. And by "anywhere" I mean "lying right there on my desk, not under a pile of paper".

So rather than waste your time with trying to find hardware you may or may not have, just say "hey, I'm not playing games anyway, so why not just drive that thing with a single DVI link at 30Hz instead of the 60Hz it wants. It's going to buffer the data somewhere to see if it needs to stretch it anyway". 

And if you are that kind of lazy git, here's what you do:

Step 1: calculate the VESA timing modes for 2560x1440 at 30Hz. You could do this by hand if you were a real man, but we already covered the whole "lazy git" part. So use the "gtf" tool (no, that's not random noise, it means "Generalized Timing Formula", it's part of the VESA standard for how the pixel signal timings are supposed to look like)

Running "gtf 2560 1440 30" spits out the following lovely turd, bringing back bad memories of X11 config files. There's a reason we don't do them any more, but people still remember it, and get occasional flashbacks and PSTD:

  # 2560x1440 @ 30.00 Hz (GTF) hsync: 43.95 kHz; pclk: 146.27 MHz
  Modeline "2560x1440_30.00"  146.27  2560 2680 2944 3328  1440 1441 1444 1465  -HSync +Vsync

Yeah, G+ will completely corrupt the formatting of those two lines, but for once it doesn't really matter. It looks like noise regardless of formatting. It's not meant for human consumption.

Step 2: tell 'xrandr' about this mode by just copying-and-pasting the numbers that gtf spit out after incanting the magic words "xrandr --newmode 2560x1440". So the command line looks something like 

   xrandr --newmode 2560x1440 146.27 2560 2680 ...

which will quietly seem to do absolutely nothing, but will have told xrandr that there's a new mode with those particular timings available.

Step 3: tie that mode to the list of modes that the HDMI1 output (which is what is connected to the DVI output, which you would have figured out by just running "xrandr" without any arguments what-so-ever) knows about:

xrandr --addmode HDMI1 2560x1440

Again, absolutely nothing appears to happen, but under the hood this has prepared us to say "yes, I really mean that". Lovely.

Step 4: actually switch to it. This is where the monitor either goes black, spectacularly blows up, or starts showing all its pixels the way it is supposed to:

xrandr --output HDMI1 --mode 2560x1440

Ta-daa! Wasn't that easy? Never mind what the manual says how you should use this monitor, we have the technology to do better than that. Or, in this case, worse than that, but whatever.

Now, obviously any sane person would ask himself why the GTF calculations aren't something that 'xrandr' just knows about, and why this isn't just a single command to say "please switch that output to 2560x1440@30". Why all the extra steps?

The answer to that question? I have absolutely no idea. Graphics driver people are an odd bunch. 
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Open Excel Application = win32com.client.Dispatch("Excel.Application") # Show Excel. Unlike PPT, Word & Excel open up "hidden" Application.Visible = 1 # Add a workbook Workbook = Application.Workbooks.Add() # Take the active sheet Base = Workbook.ActiveSheet # Add an oval.
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A pin tumbler locking mechanism illustrated and animated.

Saw this on Reddit. Trying to track down the original source, though. Will link if I figure it out.
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Pas mal la démo!
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Very nice summary on usb charging.
 
Everything you wanted to know about USB charging but were afraid to ask. The mystery behind why some USB ports are 500mA, 1000mA, 1800mA and 2100mA.
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Watching sumo from very close :) 
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In his circles
102 people
Have him in circles
59 people
Andrew Kuntjoro's profile photo
Benjamin Cathelain's profile photo
Mats Nilson's profile photo
Fred T's profile photo
Julien Bataille's profile photo
Tetsuo Narita's profile photo
rosine andreas garnier's profile photo
Loïc Simon Décar's profile photo
Tino Jehuty's profile photo
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  • Fujitsu Laboratories LTD
    Researcher, 2008 - present
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Tokyo
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French engineer living in Japan incorporated.
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Can speak fluently French, English and most of all Japanese!
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  • ESIEE
    Computer Sciences, 2002 - 2008
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パリジ マチュー
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