Literals that start with 0x are hexadecimal integers. (base 16) The number 0x6400 is 25600. For an example including letters (also used in hexadecimal notation where A = 10, B = 11 … F = 15) The number 0x6BF0 is 27632.
To understand this you’ll first need to understand pointers and references. I’ll simply explain the type declaration syntax you’re asking about assuming you already know what pointers and references are. In C, it is said that ‘declaration follows use.’ That means the syntax for declaring a variable mimics using the variable: generally in a declaration … Read more
1e5 is a number expressed using scientific notation and it means 10 to the 5th power (the e meaning ‘exponent’) so 1e5 is equal to 100000, both notations are interchangeably meaning the same.
density *= invertedRatio; is a shortened version of density = density * invertedRatio; This notation comes from C.
%w(foo bar) is a shortcut for [“foo”, “bar”]. Meaning it’s a notation to write an array of strings separated by spaces instead of commas and without quotes around them. You can find a list of ways of writing literals in zenspider’s quickref.
density *= invertedRatio; is a shortened version of density = density * invertedRatio; This notation comes from C.
1e5 is a number expressed using scientific notation and it means 10 to the 5th power (the e meaning ‘exponent’) so 1e5 is equal to 100000, both notations are interchangeably meaning the same.
Neither is more correct than the other. They just represent different values. 1e-9 is 0.000000001; the minus sign applies to the exponent. -1e9 is -1000000000.0; the minus sign applies to the number itself. The e (or E) means “times 10-to-the”, so 1e9 is “one times ten to the ninth power”, and 1e-9 means “one times ten to the negative ninth power”. In mathematical scientific notation, this … Read more
59 I need to know what += does in Python. It’s that simple. I also would appreciate links to definitions of other shorthand tools in Python.