[:] creates a slice, usually used to get just a part of a list. Without any minimum/maximum index given, it creates a copy of the entire list. Here’s a Python session demonstrating it: >>> a = [1,2,3] >>> b1 = a >>> b2 = a[:] >>> b1.append(50) >>> b2.append(51) >>> a [1, 2, 3, 50] … Read more
I’ve also been looking for a single-page “quick reference” PDF for ERD relationship symbols (i.e. “Crows Feet”). I haven’t found anything I’ve liked, so I created this. I’ve posted the Full Page, Printable PDF on my blog. Hope this helps!
Section 3.10.2 of the JLS talks about floating-point literals in Java. In short, provide the decimal part as if it were scientific notation, but instead of x 10^23 you would write e23: 3.30e23 To write one with a negative exponent, you can do that easily also for 6.67 x 10^(-11): 6.67e−11
This is a matter of personal choice. There are those that argue that dot notation makes it unclear that messages are being sent (methods are being called) since it looks just like C-style structure element access. The other side of argument is that dot notation is easier to type, easier to read, and more concise. … Read more
This is useful to setting default values to function arguments, e.g.: function test (options) { options = options || {}; } If you call test without arguments, options will be initialized with an empty object. The Logical OR || operator will return its second operand if the first one is falsy. Falsy values are: 0, … Read more
So now I wonder why Angular team decided to use it? And what does it mean? Yes, it marks methods as internal/private. Here is the quote from the article that was written by Uri Shaked who got this information from the Angular core team members: The first thing you many notice is a lot of … Read more
That’s Classless Inter-Doman Routing notation. The /24 means that the routing prefix of the subnet is 24 bits long, which means there’s ony 8 bits left for the subnet itself, i.e. 123.218.44.0 to 123.218.44.255
You are looking at the default str() formatting of floating point numbers, where scientific notation is used for sufficiently small or large numbers. You don’t need to convert this, the value itself is a proper float. If you need to display this in a different format, format it explicitly: >>> print(0.00001357) 1.357e-05 >>> print(format(0.00001357, ‘f’)) … Read more
1e5 is a number expressed using scientific notation, specifically E notation, and it means 1 multiplied by 10 to the 5th power (the ‘e’ meaning ‘exponent’). So 1e5 equals 1*100000 and is equal to 100000. The three notations are interchangeable meaning the same.
In The Development of the C Language, Dennis Ritchie explains his reasoning thusly: The second innovation that most clearly distinguishes C from its predecessors is this fuller type structure and especially its expression in the syntax of declarations… given an object of any type, it should be possible to describe a new object that gathers … Read more