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Daniel Lemire
Works at LICEF Research Center, TELUQ, Université du Québec
Attended University of Toronto
Lives in Montreal, Canada
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Daniel Lemire

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How do you get quickly the assembly output of a few lines of C? Yes, I know how to get the assembly dump of a .c file. I know how to do it, awkwardly, with a debugger... But since I have found out about http://gcc.godbolt.org/ I want to have an equivalent tool on the command line... That is, I want to be able to super quickly know the compiler output... by super quickly, I mean that I don't want to have to type complicated commands...
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In that case I usually run a local GCC Explorer.  A local version by default has access to the full filesystem (unlike the public web version).

I then paste in the -I<path> paths to the root of my project, add the few defines I need, and then I have a version that's ready-made for testing real-world code snippets.
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Funny because it is true.
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If it were really true it wouldn't be funny at all.
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Daniel Lemire

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Any C++ experts can help me clear up what  the C++ standard means by "probability"?
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Depending on the use case, one may want to use even identity as hash function for maximum performance. The need for randomized hash function mostly arises from untrusted data.
To my understanding of the standard, using a hash function randomized at startup is allowed. The initialized hash function must satisfy the requirements. I.e. "(x+b)*a" is considered a different h for each value of a, b (i would call this a hash function family). The only thing forbidden is a “dynamic rekeying” of the hash function, IMHO.
For the probabilistic part: without adding assumptions on your data (e.g. assuming uniform distribution) you can't talk much more about probabilities here. As mentioned initially, the developer must be allowed to use identity as hash function if he knows his keys are well distributed already. I concur with +Christopher Smith on this, don't limit flexibility for the “untrusted strings” example.
For the textbook part of “any”, this must not imply “uniform”.
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Barely more than 50$. You get 512MB of RAM,  a 1GHz processor, and 4GB of flash memory. There isn't a lot you can't do with a machine like that.
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You got that right!
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Daniel Lemire

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For yogurt geeks: Choosing a Yogurt Starter 
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Have him in circles
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PHK does it again. Brilliant.
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+Erich Schubert They do not cover the commercial implementations of Apple, Oracle, Microsoft and IBM, do they? Or do they appear under names I do not recognise?

Nevertheless, that pdf looks like an interesting comparison.
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I think that most people greatly underestimate the money that goes into open source software. 

c.c. +Christopher Smith 
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I don't say Linux is worthless. I've been a Debian GNU/Linux maintainer for 15+ years, and I've seen these numbers pop up every now and then.
I'm just saying that these numbers are worse than an educated guess; they are based on 1981 (!) models for the waterfall development model and COBOL.
Already in a 1987 study, "All three COCOMO models did poorly according to the MRE percentage error test."
ELKI internal has 350k SLOC, and COCOMO estimates it at 12.5 million, and 90 man years. These results are just off by a factor of 10 IMHO.
Even if the Linux kernel would be worth just 120 million (instead of 1.2 billion; in 2010), that would be a lot of effort to redevelop from scratch, obviously.
http://debian-counting.libresoft.es/lenny/index.php?menu=Statistics has the statistics for Debian GNU/Linux 5, 2009. With the COCOMO model, the schedule estimate would have been 46 years and $315 billion... the COCOMO values are not at all calibrated at this size... even 100000 developers, and 30 years, would make $100000 of value contributed by every developer every year. Here, it's probably more off by a factor of 100: 10000 developers contributing $10000 worth of additional value every year.
IMHO: forget about these numbers, they're much worse than an educated guess! Instead, examples such as Android, Linux-based Sony Bravia TVs, etc. is much better evidence that open source software is valueable.
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"Economists who assume that college attendance is driven by students' greed are largely correct." 
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The straightforward solution is to value historians by paying them more.
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In my latest blog post, I recount how I changed my mind almost entirely about learning...
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Nothing's preventing you from learning number theory now. On the other hand, what if you had taken several courses in number theory and later had no use for them? Granted, that's something you'll find out when you need it.
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Given that our smartphones will soon translate everything for us, should we bother learning a foreign language?
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+Daniel Lemire Autocorrect is still a long way from being helpful, they should focus on making this one work. Translation will be much more complicated and confusing. 
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People
Have him in circles
22,795 people
Work
Occupation
Computer scientist
Skills
indexing - information retrieval - databases - collaborative filtering
Employment
  • LICEF Research Center, TELUQ, Université du Québec
    Professor, 2004 - present
    Promoted to full professor in 2009. Funded by NSERC Discovery grants (2003-2007, 2007- 2012, 2012-2017) in computer science. Program committee member at major conferences (ACM CIKM, ACM WSDM, ACM RecSys).
  • National Research Council of Canada
    Research Officer, 2002 - 2004
    Founded and lead the e-Health research group. Designed the Slope One algorithm.
Places
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Currently
Montreal, Canada
Story
Tagline
Computer Scientist
Introduction
I have always been intensely curious and I am always scouting for new knowledge. I love to program and publish open source software.

I have had many jobs: researcher in a government laboratory, University professor, entrepreneur and consultant. 

I spent too much time on my formal education. It got me a Ph.D. and even a post-doctoral fellowship. But I consider myself to be an autodidact.

I have two great kids and a beautiful wife. I live somewhere near Montreal in a small house I love.

My home online is at http://lemire.me
Bragging rights
I drink my weight in coffee every day.
Education
  • University of Toronto
    B.Sc. (Mathematics), 1989 - 1994
    Graduated with very high distinction.
  • University of Toronto
    M.Sc. (Mathematics), 1994 - 1995
  • École Polytechnique and University of Montreal
    Ph.D. (Engineering Mathematics), 1995 - 1998
    Graduated in 2.5 years.
Basic Information
Gender
Male
Relationship
In a relationship
Daniel Lemire's +1's are the things they like, agree with, or want to recommend.
Ronin Institute
plus.google.com

The Ronin Institute: a home for the independent scholar

Open Data Structures
plus.google.com

data structures, textbook, open-source, open content, open access

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Tinycon. A small library for manipulating the favicon. Tinycon allows the addition of alert bubbles and changing the favicon image. Tinycon

Why experts exaggerate — The Endeavour
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Why experts exaggerate. by John on November 26, 2011. Seth Roberts writes this morning: How can you tell when an expert is exaggerating? His

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Automated Essay Scoring Systems as Effective as Human Graders ~ Stephen'...
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You have more choices than you think — The Endeavour
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You have more choices than you think. by John on December 10, 2011. This week Seth Godin wrote a blog post that include this gem: Remarkable

The new luxury
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Imagine, if, in today’s world, you saw someone jotting down notes in a meeting with a fine fountain pen. You know, the kind that has a cartr

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Sorry - this is an error page. We may have goofed, or you may have typed in a URL that doesn&#39;t exist. Try these pages instead: About Thi

…research shows that knowledge workers actually...
blog.vivekhaldar.com

“…research shows that knowledge workers actually have fewer good hours in a day than manual laborers do — on average, about six hours, as op

Knowing and Doing: February 2013 Archives
www.cs.uni.edu

It is a commonplace for anyone who has taught that we learn a lot more about any topic when we teach it -- even a topic in which we are ackn

Do we need copyright?
lemire.me

The concept of property is a social construction. Animals, such as cats, can own a piece of food, or a territory, but only as long as they a

Are Relational Databases good for anything anymore?
lemire.me

Are Relational Databases good for anything anymore? (Note: thanks to Daniel for letting me use his blog. All comments, questions and critici

ON: ‘Fat tax’ won’t solve obesity | Canadian Taxpayers Federation
taxpayer.com

A not-for-profit citizen's advocacy group dedicated to lower taxes, less waste and accountable government.

ongoing by Tim Bray · Seasonal Shinies
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Seasonal Shinies. Search. Today we took down the Christmas tree. Christmas tree decorations. The pile of decorations is smaller than it was

Freakonomics: What Went Wrong? ~ Stephen's Web
www.downes.ca

Stephen's Web, the home page of Stephen Downes, with news and information on e-learning, new media, instructional technology, educational de

Seth's Blog » Blog Archive » Duct Tape, the Eurozone, Status-Quo Bias...
blog.sethroberts.net

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Seth's Blog » Blog Archive » Assorted Links
blog.sethroberts.net

I Recommend. The Great Stagnation by Tyler Cowen. The Man Who Would Be Queen by Michael Bailey. Feynman&#39;s Rainbow by Leonard Mlodinow. M

Seth's Blog » Blog Archive » Steve Jobs’ Graduation Speech: My Opinion
blog.sethroberts.net

I Recommend. The Great Stagnation by Tyler Cowen. The Man Who Would Be Queen by Michael Bailey. Feynman&#39;s Rainbow by Leonard Mlodinow. M