Feng divide the VRPTW with delivery and pickup into five categories. In 1981, Schrage proposed vehicle routing and scheduling problem with time window constraints as an important area for progress in handling realistic complications and generalizations of the basic routing model. Many researchers have contribute to the problem. The objective of the VRPTW is to minimize the total transport costs. Each customer should be served exactly once. It starts from the depot and terminates at the depot. The problem can be described as choosing routes for limited number of vehicles to serve a group of customers in the time windows.
#TIME MATLAB 2012 WINDOWS#
Vehicle routing problem with time windows (VRPTW) is an important issue in logistics system which has been researched widely in recent years. Finally, comparing with genetic algorithm (GA) and particle swarm optimization (PSO) algorithm, the MCPSO algorithm performs best for solving this problem. And a new encoding method is proposed for the extension VRPTW. To solve the problem, an efficient multiswarm cooperative particle swarm optimization (MCPSO) algorithm is applied. Using minimization of the total transport costs as the objective of the extension VRPTW, a mathematic model is constructed. The two factors, which are very common characteristics in realworld, are uncertain number of vehicles and simultaneous delivery and pick-up service. The datestr function is useful for preparing output reports.This paper considers two additional factors of the widely researched vehicle routing problem with time windows (VRPTW). The default output for dates is a day-month-year character vector, for example, 2.
#TIME MATLAB 2012 SERIAL#
The datestr function converts a serial date number to one of 19 different date character vector output formats showing date, time, or both. For more information, see Character Vector Input. To ensure that the character vectors are the same length, fill the character vectors with spaces or zeros. Remember that if you create a vector of input date character vectors, use a column vector, and be sure that all character vectors are the same length. Alternately, serial date numbers are just another type of numeric data, which you can place in a matrix along with any other numeric data for convenient manipulation. For example, when formatting data for visual display or for debugging date-handling code, you can view dates more easily as date character vectors because serial date numbers are difficult to interpret. The decision to represent dates as either date character vectors or serial date numbers is often a matter of convenience. For example, all the following are character vectors represent Augat 04:35:42 PM: There are several ways to represent dates and times in several text formats. Convert Between Datetime Arrays and Character VectorsĪ date can be a character vector composed of fields related to a specific date and time. Ĭonverts MATLAB serial date number to Excel ® serial date number.Įxcel serial date number to MATLAB serial date number.įor more information, see Convert Between Datetime Arrays, Numbers, and Text. In addition, you can convert character vectors or serial date numbers to datetime arrays.įunctions that convert between date formats are:ĭisplays a numeric matrix with date entries formatted as date character vectors.Ĭonverts a date character vector to a serial date number.Ĭonverts a serial date number to a date character vector.Ĭonverts from date character vectors or serial date numbers to create a datetime array.Ĭonverts a serial date number or date character vector to a date vector whose elements are. Date Conversionsįinancial Toolbox provides functions that convert date character vectors to or from serial date numbers. For more information, see Represent Dates and Times in MATLAB. If you are using Financial Toolbox functions on large numbers of dates, as in analyzing large portfolios or cash flows, performance improves if you use datetime arrays or serial date numbers. If you are dealing with a few dates at the MATLAB command-line level, date character vectors are more convenient. Many Financial Toolbox functions that require dates as input arguments accept date character vectors, datetime arrays, or serial date numbers. However, whenever possible, use serial date numbers or date character vectors containing four-digit years. MATLAB internal date handling and calculations generate no ambiguous values. See the function datenum for specific information. If you specify a two-digit year, MATLAB assumes that the year lies within the 100-year period centered on the current year.