Communications of the ACM
Refine your search:
How the “Frontier” Became the Slogan of Uncontrolled AI
Artificial intelligence (AI) has been billed as the next frontier of humanity: the newly available expanse whose exploration …
From Daniel Lemire's Blog
How many digits in a product?
We often represent integers with digits. E.g., the integer 1234 has 4 digits. By extension, we use ‘binary’ digits, called bits, within computers. Thus the integer...
From Daniel Lemire's Blog
The end of the monopolistic web era?
Except maybe in totalitarian states, you cannot ever have a single publisher. Most large cities had multiple independent newspapers. In recent years, we saw a surge...
From Daniel Lemire's Blog
SWAR explained: parsing eight digits
It is common to want to parse long strings of digits into integer values. Because it is a common task, we want to optimize it as much as possible. In the blog post...
From Daniel Lemire's Blog
What is the ‘range’ of a number type?
In programming, we often represent numbers using types that have specific ranges. For example, 64-bit signed integer types can represent all integers between -9223372036854775808...
From Daniel Lemire's Blog
How programmers make sure that their software is correct
Our most important goal in writing software is that it be correct. The software must do what the programmer wants it to do. It must meet the needs of the user.Continue...
From Daniel Lemire's Blog
Science and Technology links (December 19th 2021)
Becoming a physician increases the use of antidepressants, opioids, anxiolytics, and sedatives, especially for female physicians. When trying to reproduce results...
From Daniel Lemire's Blog
Science and Technology links (December 4th 2021)
It used to be that all the exciting new processors came from Intel and AMD, and they were meant for your PC. The mobile revolution changed that: it lead to theContinue...
From Daniel Lemire's Blog
Can you safely parse a double when you need a float?
In C as well as many other programming languages, we have 32-bit and 64-bit floating-point numbers. They are often referred to as float and double. Most of systems...
From Daniel Lemire's Blog
Science and Technology links (Novembre 28th 2021)
Government-funded research is getting more political and less diverse: The frequency of documents containing highly politicized terms has been increasing consistently...
From Daniel Lemire's Blog
Are tenured professors more likely to speak freely?
University professors often have robust job security after a time: they receive tenure. It means that they usually do not have to worry about applying for a new...
From Daniel Lemire's Blog
Converting integers to fix-digit representations quickly
It is tricky to convert integers into strings because the number of characters can vary according to the amplitude of the integer. The integer ‘1’ requires a single...
From Daniel Lemire's Blog
Science and Technology links (Novembre 13rd 2021)
Pacific rougheye rockfish can live hundreds of years while other rockfish barely live past ten years. Female condors can reproduce without males. The phenomenon...
From Daniel Lemire's Blog
Checking simple equations or inequalities with z3
When programming, you sometimes need to make sure that a given formula is correct. Of course, you can rely on your mastery of high-school mathematics, but human...
From Daniel Lemire's Blog
Stop spending so much time being trolled by billionaire corporations!
As a kid, my parents would open the television set, and we would get to watch whatever the state television decided we would watch. It was a push model. Some experts...
From Daniel Lemire's Blog
Science and Technology (October 31st 2021)
Though exoskeletons are exciting and they allow some of us to carry one with physical activities despite handicaps, they appear to require quite a bit of brainContinue...
From Daniel Lemire's Blog
In C, how do you know if the dynamic allocation succeeded?
In the C programming language, we allocate memory dynamically (on the heap) using the malloc function. You pass malloc a size parameter corresponding to the number...
From Daniel Lemire's Blog
In C++, is empty() faster than comparing the size with zero?
Most C++ programmers rely on “STL” for their data structures. The most popular data structure is probably vector, which is just a dynamic array. The set and the...
From Daniel Lemire's Blog
Science and Technology links (October 23rd 2021)
Apple announced new processors for its computers. Here is a table with the transistor count of some recent Apple processors: processor release year transistorsContinue...
From Daniel Lemire's Blog
Converting binary floating-point numbers to integers
You are given a floating-point number, e.g. a double type in Java or C++. You would like to convert it to an integer type… but only if the conversion is exact.Continue...
From Daniel Lemire's Blog