A typical diffusion constant for a medium-sized molecule in water is about . If we want the smell to travel a quarter mile, or a little less than , we get a speed of. This speed is fantastically slow, and says that it would take ten million years for blood to diffuse out to a shark a quarter mile away.
XML Parser. A parser is a piece of program that takes a physical representation of some data and converts it into an in-memory form for the program as a whole to use. Parsers are used everywhere in software. An XML Parser is a parser that is designed to read XML and create a way for programs to use XML. There are different types, and each has its advantages. Unless a program simply and blindly copies the whole XML file as a unit, every program must implement or call on an XML parser.
PHP SimpleXML Parser. SimpleXML is a PHP extension that allows us to easily manipulate and get XML data. The SimpleXML Parser. SimpleXML is a tree-based parser. SimpleXML provides an easy way of getting an element's name, attributes and textual content if you know the XML document's structure or layout. SimpleXML turns an XML document into a data structure you can iterate through like a collection of arrays and objects.