How to measure the area of a circle
Well if you remember maths (or math for US readers), you’ll know that the area of a circle is pi X r X r where r is the radius and pi is that 3.14159 number.
But what if you are given a weird shape instead of a circle? Like some of those in the picture.
There’s a method called Monte Carlo because of the casino there. In effect you simulate throwing darts at the shape (say printed out and stuck on the wall). You throw thousands or millions of darts and count how many hit the particular shape and how many darts were thrown in total. You only count those that hit the rectangular paper; those that miss it don’t count.
Then you divide the number of hits by the number thrown, multiply it by the width and height of the picture (which is rectangular or square) and that is a close approximation to the area. In more advanced ,maths/math, this method is sometimes used to calculate the integral of a function. The integral is the area under the function. Some complicated functions are particularly hard to integrate, so using a Monte Carlo method can solve it for you.
I’ll publish a C program to run Monte Carlo on an image in a day or two.
An alternative way of measuring the area is by using recursion. I discussed it in this article Using recursive fill to count maps.
This is for my MMO game. I need a backend server, so yesterday I signed up for a vps service. I picked Ubuntu 20.04 LTS which I’ve used before and received the login details. I use Putty to log in via SSH and WinSCP for browsing, copying files. Installing Apache2 is actually very easy. Likewise PHP. I didn’t install MySQL which might have been a mistake, so I had a LAP system (Linux, Apache, PHP) rather than LAMP.
It’s true. Well my code and that of thousands of others on Svalbard, a set of islands halfway between Norway and the North pole. I’ve actually been to Svalbard on a cruise a few years back. It was cold and a bit damp. That’s one of a bunch of photos I took.
I occasionally answer (often in a somewhat ascerbic tone) questions on 
This is more of a tip, but it can be a useful thing to know. If you look at this photo you’ll see it contains a bunch of words. Now you could type them in but that’s a bit tedious.
I noticed that the Covid lockdown had made streaming of chess games very popular and did a search to see if I could find the source of one in C. The first one I found was actually C++ (cout << is a bit of a giveaway!) but I found this one by a developer called 
This assumes that you have the version 2004 of Windows 10. Run the command Winver (open a command line then type winver) to see what version you have.
Just click it and your Ubuntu (or whatever) Linux will open at a terminal prompt like this.