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Shunting Yard
Shunting yard may refer to: * Classification yard * Shunting yard algorithm * British term for rail yard A rail yard, railway yard, railroad yard (US) or simply yard, is a series of tracks in a rail network for storing, sorting, or loading and unloading rail vehicles and locomotives. Yards have many tracks in parallel for keeping rolling stock or u ... {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classification Yard
A classification yard (American and Canadian English ( Canadian National Railway use)), marshalling yard (British, Hong Kong, Indian, Australian, and Canadian English ( Canadian Pacific Railway use)) or shunting yard (Central Europe) is a railway yard found at some freight train stations, used to separate railway cars onto one of several tracks. First the cars are taken to a track, sometimes called a ''lead'' or a ''drill''. From there the cars are sent through a series of switches called a ''ladder'' onto the classification tracks. Larger yards tend to put the lead on an artificially built hill called a ''hump'' to use the force of gravity to propel the cars through the ladder. Freight trains that consist of isolated cars must be made into trains and divided according to their destinations. Thus the cars must be shunted several times along their route in contrast to a unit train, which carries, for example, cars from the plant to a port, or coal from a mine to the power plan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shunting Yard Algorithm
In computer science, the shunting yard algorithm is a method for parsing arithmetical or logical expressions, or a combination of both, specified in infix notation. It can produce either a postfix notation string, also known as Reverse Polish notation (RPN), or an abstract syntax tree (AST). The algorithm was invented by Edsger Dijkstra and named the "shunting yard" algorithm because its operation resembles that of a railroad shunting yard. Dijkstra first described the shunting yard algorithm in the Mathematisch Centrum reporMR 34/61 Like the evaluation of RPN, the shunting yard algorithm is stack-based. Infix expressions are the form of mathematical notation most people are used to, for instance or . For the conversion there are two text variables (strings), the input and the output. There is also a stack that holds operators not yet added to the output queue. To convert, the program reads each symbol in order and does something based on that symbol. The result for the above ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
