Daniel Lemire 
There are various ways in software to handle error conditions. In C or Go, one returns error code. Other programming languages like C++ or Java prefer to throw exceptions. One benefit of using exceptions is that it keeps your code … Read more
In C, the length of a string in marked by a 0 byte at the end of the string. Thus to determine the length of the string, one must scan it, looking for the 0 byte. Recent ARM processors have … Read more
Let us say that I ask you to find the number I am thinking about between -1000 and 1000, by repeatedly guessing a number. With each guess, I tell you whether your guess is correct, smaller or larger than my … Read more
Modern processors have powerful vector instructions which allow you to load several values at once, and operate (in one instruction) on all these values. Similarly, they allow you to have vector constants. Thus if you wanted to add some integer … Read more
Modern game controllers can point in a wide range of directions. Game designers sometimes want to convert the joystick direction to get 8-directional movement. A typical solution offered is to compute the angle, round it up and then compute back the … Read more
In the first half of the XXth century, there were relatively few scientists, and these scientists were generally not lavishly funded. Yet it has been convincingly argued that these scientists were massively more productive. We have entered a ‘dark age’ … Read more
When programming, we often need to write ‘generic’ functions where the exact data type is not important. For example, you might want to write a simple function that sums up numbers. Go lacked this notion until recently, but it was … Read more
Many recent Intel processors benefit from a new family of instructions called AVX-512. These instructions operate over wide registers (up to 512 bits) and follow the Single instruction, multiple data (SIMD) paradigm. These new AVX-512 instructions allow you to break some … Read more
In software, it is a common problem to want to remove specific characters from a string. To make the problem precise, let us consider the removal of all ASCII control characters and spaces. In practice, it means the removal of … Read more
At my university, one of our internal software systems allows a professor to submit a revision to a course. The professor might change the content or the objectives of the course. In a university, professors have extensive freedom regarding course … Read more