JP5036573B2 - Network generation device for total minimum cost route search, generation method, and route search device using this network - Google Patents

Description

  The present invention relates to a network generation apparatus and a generation method for searching all minimum cost paths between two points, and more particularly to an apparatus for generating an entire minimum cost path search network suitable when there are a plurality of minimum cost paths, and It relates to a generation method. The present invention also relates to a route search apparatus using this network.

  As an example of searching for a minimum cost route between two points, for example, there is a railway fare calculation between a departure station and an arrival station. Railway fare calculation uses, for example, a network in which stations are nodes, arcs are tracks connecting stations, and arc costs are distances, and the shortest route (minimum cost route) is searched for among the available routes between two stations. The fare is calculated by converting the distance of the searched route into the fare. Further, when calculating the railway fare, if there are a plurality of shortest routes between the departure and arrival stations, it is necessary to obtain all of them. Furthermore, there is a need to obtain the lowest fare between the departure station and the arrival station. At that time, if there are a plurality of the lowest fare routes between the departure and arrival stations, all of them must be obtained.

As a conventional method for searching for a plurality of such minimum cost routes, a method for obtaining all routes existing between two nodes on the network and selecting a route with the lowest cost from among them, and a k-shortest route There is a method using a search algorithm. In addition, there exist some which were described in patent document 1, 2 regarding the several shortest path search method using a k-shortest path search algorithm.
JP-A-5-46590 JP 2004-61298 A

  However, the above-described method for searching all routes requires calculation of all routes, and the amount of calculation is very large. Therefore, when the network scale is large, it is difficult to search in a practical processing time. There is a problem. The method using the k-shortest route search algorithm is an algorithm for obtaining routes in ascending order of cost, and is a mechanism for performing a search until a route having a cost higher than the minimum cost route is obtained. Accordingly, although the calculation amount is smaller than that of the all-route search method, there is still a lot of useless calculation, and searching for all the routes with the lowest cost (minimum cost route) takes time and is not efficient.

  The present invention has been made paying attention to the above-mentioned problems, and is an all-minimum-cost route search that generates a network that can efficiently and quickly search all the minimum-cost routes (for example, the shortest route, the cheapest fare route, etc.). An object of the present invention is to provide a network generation device and a generation method for use. It is another object of the present invention to provide a route search apparatus to which this network is applied.

  Therefore, the network generation device for total minimum cost path search according to the present invention described in claim 1 has an original path having a plurality of nodes, connecting adjacent nodes by arcs, and setting a cost for each arc. A data storage unit for storing search network data, and any one of the plurality of nodes as a termination node, and the minimum cost of each path from each node to the termination node with respect to all nodes including the termination node, respectively Calculate and convert the cost of each arc of the original route search network based on the calculated minimum cost and the cost of each arc of the data storage unit, and connect the arc after the conversion is zero and the arc A network data generation unit that generates minimum cost path network data composed of only the nodes to be configured. It is characterized in.

  In such a configuration, the network data generation unit calculates the minimum cost from each node to the terminal node including the terminal node based on the original network data stored in the data storage unit, The cost of each arc is converted from the cost of the arc, and the minimum cost path network data including only the arc having the converted cost of zero and the node connected by the arc is generated. In the minimum cost path network constructed with the minimum cost path network data, the paths from each node to the end node are all the minimum cost paths. As a result, all the minimum cost paths existing between the two nodes can be searched in a short time.

  Specifically, the network data generation unit, as in claim 2, a cost calculation means for calculating the minimum cost, an arc cost conversion means for converting the cost of each arc of the original route search network, Arc deleting means for deleting arc data whose cost is not zero from arc cost conversion network data composed of the nodes and arcs stored in the data storage unit and the converted cost obtained by the arc cost converting means. The minimum cost path network data is generated by deleting arc data with a non-zero cost from the arc cost conversion network data.

Specifically, as described in claim 3, the arc cost conversion means determines the minimum cost to the end node calculated by the minimum cost calculation means for the node that is the starting point of the arc to be converted, as Ctail, For the node that is the end point of the arc to be converted, the minimum cost to the end node calculated by the minimum cost calculating means is Chead, and the cost before conversion of the arc to be converted that connects the start point node and the end point node. For all arcs stored in the data storage unit, the converted cost HCarc is expressed by the following equation:
HCarc = Chead + Carc-Ctail
It was set as the structure calculated using.

5. The network data generation unit according to claim 4, comprising cost quantization means for quantizing the cost of each arc of the original route search network according to a predetermined rule, and the cost quantization by the cost quantization means. It is preferable that the minimum cost calculation process be performed after the process.
In such a configuration, the cost of each arc in the original route search network is quantized by the cost quantization means, and then the minimum cost route search network data is generated through the minimum cost calculation process and the cost conversion process. Thereby, minimum cost route search network data capable of searching a plurality of routes having a cost close to the minimum cost in the original route search network can be generated.

According to a fifth aspect of the present invention, the arc cost type is any one of distance, time, and amount.
As a result, if the cost type is distance, the shortest distance route is short, if the cost type is time, the shortest time route is short, and if the cost type is fares, the cheapest route is short. You can search in time.

  Further, the network generation method for total minimum cost path search according to the present invention described in claim 6 has a plurality of nodes, is configured by connecting adjacent nodes with arcs, and setting a cost for each arc, A step of selecting any one of the plurality of nodes of the original route search network data stored in advance as a termination node, and the termination node from each node with respect to all nodes including the termination node selected in the selection step Each of the original route search network based on the minimum cost calculated in the minimum cost calculation step and the cost of each arc in the data storage unit. An arc cost converting step for converting an arc cost, the node and arc of the data storage unit, and the arc; The arc cost conversion network data composed of the cost converted in the cost conversion step deletes arc data with a non-zero cost from the network data, and the minimum cost is composed only of the zero-cost arc and the nodes connected by the arc. A network data generation step of generating route network data.

  A route search device according to a seventh aspect of the present invention includes an input unit that inputs information about a start end and a terminal end of a route search target, and an all minimum cost route according to any one of the first to fifth aspects. Using the network data storage unit storing the minimum cost route network data generated by the network generation device for search and the minimum cost route network constructed by the minimum cost route network data of the network data storage unit, input at the input unit A route search unit that searches for at least one or more routes between the start and end points, and an output unit that outputs route information searched by the route search unit and cost information of the route It is characterized by.

  In such a configuration, when the start and end information is input at the input unit, the route search unit constructs a minimum cost route network based on the minimum cost route network data stored in the network data storage unit, and ends from the input start point to the end point. Search for at least one route (all or any number) up to. All the searched routes are the least cost routes. The output unit outputs searched route information and cost information of the route.

As in claim 8, the minimum cost route network data generated by the network generation device according to claim 4 is stored in the network data storage unit, and the route search unit between the start end and the end point It is preferable that at least one (all or any number) of routes having a cost close to the minimum cost in the original route search network can be searched.
In such a configuration, for example, when searching for a route with a short distance to the end and a short time required using a route search network in which the arc cost is a distance, all the routes that are closest to the shortest route are searched and searched. If time is weighted for all the routes, a route optimum for the search condition can be searched.

  According to the present invention, since the minimum cost path network constructed by the minimum cost path network data is a network connected by only the minimum cost path, all the minimum cost paths from the start end to the end can be searched in a short time. A network can be provided. In addition, if this minimum cost route network is used, if there are multiple routes with the cheapest fare, such as railway fare calculation, all the cheapest fare can be searched in a short time even if it is necessary to search all of them. The route can be searched.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiment, an example will be described in which the arc cost is a distance and the minimum cost route search is applied to the shortest route search.
FIG. 1 is a block diagram showing a configuration of a first embodiment of a route search apparatus according to the present invention. FIG. 2 shows a network in which stations are nodes, lines connecting stations are arcs, and arc costs are distances. This is called an original route search network.
In FIG. 1, the route search device 1 of the present embodiment has a function of generating shortest route network data as minimum cost route network data as will be described later, and also serves as a network generation device for minimum cost route search.

  The route search device 1 includes an input unit 2, a data storage device 3, a shortest route network data generation unit 4, a storage device 5, a route search unit 6, and an output unit 7. Here, the route search device 1 is configured by a computer, for example, and the functions of the shortest route network data generation unit 4 and the route search unit 6 are provided in software.

The input unit 2 is for inputting each data of a starting point as a starting point and an arriving point as a terminal point.
The data storage device 3 has a plurality of nodes, connects adjacent nodes with arcs, and sets the distance to each arc as a cost, for example, network data for constructing an original route search network as shown in FIG. Is equivalent to a data storage unit.

  The shortest path network data generation unit 4 determines all the shortest paths (minimum cost paths) existing between the departure point and arrival point nodes based on the original route search network data stored in the data storage device 3. In order to search, it is necessary to construct a shortest path network. The shortest path network data is generated for this purpose, and includes a shortest path search unit 4A, an arc cost conversion unit 4B, and an arc deletion unit 4C. The shortest path network data generation unit 4 corresponds to a network data generation unit.

  In the original route search network 10 of FIG. 2, the shortest route search unit 4A sets any one of a plurality of nodes as a termination node, and all the nodes including the termination node from each node to the termination node. The minimum cost of the route is calculated, and corresponds to the minimum cost calculation means. As a method for calculating the minimum cost, a shortest path search algorithm such as the Dijkstra method can be used in this embodiment.

  The arc cost conversion unit 4B is based on the minimum cost calculated by the shortest path search unit 4A and the cost data of each arc that constructs the original path search network 10 of FIG. The cost of each arc of the original route search network 10 of FIG. 2 is converted using an arithmetic expression described later, and corresponds to arc cost conversion means. By this arc cost conversion processing, network data for constructing the arc cost conversion network 20 is generated by replacing the arc cost of the original route search network with the converted cost as shown in FIG.

  The arc deleting unit 4C deletes arc data whose cost is not zero from the construction data of the arc cost conversion network 20 of FIG. 3, and thereby the final shortest path network 30 as shown in FIG. Shortest path network data for construction is generated.

The storage device 5 stores the shortest path network data generated by the shortest path network data generation unit 4 and corresponds to a network data storage unit.
The route search unit 6 searches all routes from the shortest route network 30 of FIG. 4 constructed by the shortest route network data stored in the storage device 5.
The output unit 7 outputs the route information searched by the route search unit 6 and the cost information of the route (which is distance information in the present embodiment).

  Next, each operation | movement of the production | generation of the shortest route network data by the route search apparatus 1 of this embodiment and the shortest route search using the shortest route network data is demonstrated with reference to the flowchart of FIG. In the following description, it is assumed that in the original route search network 10 of FIG. 2, the starting point is the node f, the arrival point is the node a, and the entire shortest route from the node f to the node a is searched.

FIG. 5 is a flowchart showing the operation from the generation of the shortest path network data to the search for the shortest path.
In step S1, the input unit 2 inputs information on the departure point and arrival point.
In step S2, the shortest route search unit 4A of the shortest route network data generation unit 4 calculates the cost of the shortest route from each of the nodes a to f to the arrival node a in the original route search network 10 of FIG. These costs can be efficiently calculated by a method of calculating the shortest path from one point to all points, such as the Dijkstra method. In FIG. 2, the numbers surrounded by squares near each node represent the minimum cost from each node to the arrival node a, and the other numbers represent the cost of each arc connecting between adjacent nodes. Yes. Step S2 corresponds to a terminal node selection step and a minimum cost calculation step.

  In step S3, the arc path conversion unit 4B of the shortest path network data generation unit 4 uses the minimum path calculated by the shortest path search unit 4A and the cost of each arc shown in FIG. The cost of each arc in the search network 10 is converted, and network data for constructing the arc cost conversion network 20 in FIG. 3 is generated. Step S3 corresponds to an arc cost conversion step.

Here, the arc cost conversion process will be described in detail.
The arc cost conversion unit 4B uses Ctail as the minimum cost to the end node calculated by the shortest path search unit 4A for the node that is the starting point of the cost conversion target arc, and the node that is the end point of the cost conversion target arc. 2 for all arcs of the original route search network 10 in FIG. 2, where Chead is the calculated minimum cost to the end node and Carc is the cost before conversion of the arc to be converted that connects between the start node and the end node. The later cost HCarc is calculated using the following arithmetic expression (1).
HCarc = Chead + Carc-Ctail (1)
For example, when the cost of the arc connecting node d and node e is converted, since Chead = 4, Carc = 3, and Ctail = 2 for the arc having node d as the start point and node e as the end point, HCarc = 5. On the other hand, with respect to the arc having node d as the end point and node e as the start point, Chead = 2, Carc = 3, and Ctail = 4, so HCarc = 1. When the cost of the arc connecting node c and node f is converted, since Chead = 6, Carc = 2, and Ctail = 4 for the arc starting at node c and ending at node f, HCarc = 4. With respect to the arc having node c as the end point and node f as the start point, Chead = 4, Carc = 2, and Ctail = 6, so HCarc = 0. When the costs of all arcs of the original route search network 10 in FIG. 2 are thus converted, network data for constructing the arc cost conversion network 20 in which the arc costs are converted as shown in FIG. 3 is generated. .

  In step S4, the arc deletion unit 4C of the shortest path network data generation unit 4 deletes arc data having a cost other than zero from the network data for constructing the arc cost conversion network 20 of FIG. As a result, the shortest path network data for constructing the shortest path network 30 of FIG. 4 composed only of arcs of zero cost and nodes connected by the arcs is generated. The generated shortest path network data is stored in the storage device 5. Step S4 corresponds to a network data generation step. Steps S1 to S4 described above are a function for generating shortest path network data.

In step S5, the route search unit 6 uses the shortest route network 30 of FIG. 4 constructed from the shortest route network data stored in the storage device 5, and uses the shortest route network 30 of FIG. Search all routes to In the shortest path network 30 of FIG. 4, enumeration of all paths from the starting point f to the arrival point a is as follows.
f → e → a
f → e → b → a
f → b → a
f → c → b → a
All of these routes have the cost “6” in the original route search network 10 of FIG. 2 and are the shortest routes.

Here, the validity of the shortest path network 30 of FIG. 4 will be described with reference to FIG.
The validity of the shortest path network 30 in FIG. 4 can be shown by obtaining a condition for the arc z in FIG. 6 to be an arc constituting the shortest path. In FIG. 6, the shortest distance when reaching the destination from point x through arc z via point y is the shortest distance (minimum cost) from point y to the destination, and Carc is arc z. The cost is represented by Cy + Carc. If this distance is equal to the shortest distance Cx from the point x to the destination, the arc z is an arc constituting the shortest path. At this time, the following conditions are satisfied.
Cy + Carc-Cx = 0
This equation is a case where HCarc = 0 in the above-described arithmetic expression (1). Therefore, the arc where HCarc = 0 is the arc that forms the shortest path. Therefore, it can be said that the shortest path network 30 of FIG. 4 is valid.

  In step S6, search route information and its cost information are output from the output unit 7 based on the search result of step S5.

  According to this embodiment, since the shortest path network 30 in FIG. 4 is a network composed of only the shortest path, all the routes obtained by this shortest path network are the shortest paths. Therefore, since a useless route other than the shortest route is not searched, even when it is necessary to search all the shortest routes between two points, it can be performed extremely efficiently and at high speed.

  When searching for all the shortest paths between two nodes, the full path search may be performed on the shortest path network 30 in FIG. Further, not only the entire route search but also an arbitrary number of route searches can be performed. In this case, the route search may be performed as many times as desired on the shortest route network 30 in FIG. As a route search method in this case, a general method such as a depth-first search can be used.

Further, the shortest path network 30 in FIG. 4 is a network created for obtaining the shortest path from the node f to the node a. If the arrival nodes are the same, the shortest path network 30 in FIG. It can also be used to search for the shortest route from another node b to e other than the node f to the arrival node a.
For example, in the shortest path network 30 of FIG. 4, there are the following two types of paths from the node e to the node a.
e → a
e → b → a
These routes are also the shortest route with a cost of “4” in the original route search network 10 of FIG.

  Therefore, when searching for the shortest route between all two nodes on the route search network, the number of conversions from the original route search network 10 in FIG. 2 to the shortest route network 30 in FIG. The number of nodes on the route search network 10 may be as many as the number of nodes on this route search network 10.

  In the above embodiment, every time node information of an arrival point is input, the shortest path network data having the node as an arrival node is generated. However, the present invention is not limited to this. For example, the shortest route network data, which is the arrival point, is created in advance and stored in the storage device 5 for all nodes in the original route search network 10 constructed with the stored data in the data storage device 3. May be. Alternatively, for all nodes in the original route search network 10, the shortest route network data of all combinations of departure points and arrival points may be created in advance and stored in the storage device 5.

The shortest path search operation according to the former configuration is as shown in the flowchart of FIG.
In step S11, the starting point and the arrival point obtained by the input unit 2 are input.
In step S12, the route search unit 6 selects and reads the shortest route network data having the input arrival point as the arrival node from the shortest route network data created in advance and stored in the storage device 3.
In step S13, the route search unit 6 calculates all routes from the starting point using the shortest route network constructed from the called shortest route network data.
In step S14, the search route information and its cost information are output from the output unit 7.

The shortest path search operation by the latter configuration is as shown in the flowchart of FIG.
In step S21, the starting point and the arrival point obtained by the input unit 2 are input.
In step S22, the shortest route network data having the input departure point and arrival point as the departure node and arrival node, respectively, among the shortest route network data created in advance by the route search unit 6 and stored in the storage device 3. Select to read.
In step S23, the route search unit 6 calculates all routes using the shortest route network constructed from the read shortest route network data.
In step S24, the search route information and its cost information are output from the output unit 7.

  If the route search device of this embodiment is used, network data for constructing the shortest route network as shown in FIG. 4 as shown in the flowchart of FIG. 5 based on network data with nodes as stations and arc costs as distances. If the entire route search is performed with the shortest route network as shown in FIG. 4 constructed with the created shortest route network data, all the cheapest fare routes existing between two given stations are efficiently shortened. It becomes possible to search in time.

  By using a network where each station is a node, all nodes in the same fare system are directly connected to each other by arc, and the connection weight between nodes connected by arc is a fare based on the fare triangle table data All cheapest fare routes that exist between two given stations can be found. That is, based on the above-mentioned fare network data, network data for constructing the cheapest fare route network as shown in FIG. 4 is created as the minimum cost route network as shown in the flowchart of FIG. By searching for all routes in the lowest fare route network as shown in Fig. 4 constructed with data, it is possible to efficiently and quickly search for all the lowest fare routes that exist between two given stations. Become

Next, a second embodiment of the present invention will be described.
FIG. 9 is a block diagram showing the configuration of the second embodiment of the route search apparatus according to the present invention. In addition, the same code | symbol is attached | subjected to the same element as 1st Embodiment, and description is abbreviate | omitted.
In FIG. 9, the route search device 1 of the present embodiment has the same configuration as that of the first embodiment, except that an arc cost quantization unit 4D is added to the shortest route network data generation unit 4 as quantization means.

  The arc cost quantizing unit 4D quantizes the cost of each arc in the original route search network according to a predetermined rule. Here, quantization is to replace an actual numerical value with a close representative value according to a predetermined rule. For example, a predetermined numerical range including rounding, rounding down, rounding up, and a representative value is set. Although a method of replacing a numerical value within the range with a representative value is conceivable, the method is not limited to these methods.

Next, each operation | movement of the production | generation of the shortest route network data by the route search apparatus 1 of 2nd Embodiment and the shortest route search using the shortest route network data is demonstrated with reference to the flowchart of FIG.
In step S31, the input unit 2 inputs information on the departure point and arrival point.
In step S32, the cost of each arc in the original route search network data is quantized. For example, when the original route search network data stored in the data storage device 3 is data for constructing the route search network 40 as shown in FIG. 11, the costs are rounded down to less than 100 as shown in FIG. Replace with a representative value.

  After this quantization, the route search network 40 ′ in FIG. 12 is regarded as the original route search network data, and the same operations as those in steps S2 to S6 in the first embodiment shown in FIG. 5 are performed in steps S33 to S37. Run sequentially. As a result, network data for constructing the shortest path network 50 of FIG. 13 composed of only arcs with zero cost and nodes connected by the arcs is generated. The numbers surrounded by squares in FIG. 13 represent the minimum cost from each node to the arrival node a.

  According to the second embodiment, it is possible to cause a plurality of shortest (minimum cost) paths to exist by quantizing the arc cost. In the original route search network 40 of FIG. 11, the shortest route from the node f to the node a is one of f → c → b → a, but in the route search network 40 ′ after quantization of FIG. There are four types: f → c → b → a, f → e → d → a, f → e → b → a, f → e → a, and the shortest path network 50 of FIG. Yes. These routes are close to the shortest route, and it is possible to search all or an arbitrary number of routes close to the shortest by quantizing.

  In the route search device using the shortest route network with the quantized cost, for example, when searching for a route with a short distance and a short time to the destination by car navigation, search for all the routes closest to the shortest, It is possible to search for an optimum route by weighting each searched route (for example, the degree of required time based on traffic jam information, traffic history, accident information, etc.).

  Note that the cost added to the arc in the network may be any distance, amount, time, or the like.

The block diagram which shows the structure of 1st Embodiment of the fee calculation apparatus which concerns on this invention. Diagram showing an example of an original route search network Diagram showing an arc cost conversion network based on the network of FIG. The figure which shows the example of the shortest path network based on the network of FIG. The flowchart explaining the route search operation of the first embodiment. Explanatory diagram of the validity of the shortest path network of the present invention Flowchart for explaining route search operation when shortest route network data for each arrival point is stored Flowchart explaining route search operation when shortest route network data of all combinations of arrival point and departure point is stored The block diagram which shows the structure of 2nd Embodiment of the fee calculation apparatus which concerns on this invention. Flowchart for explaining the route search operation of the second embodiment Diagram showing an example of the original route search network before quantization The figure which shows the example of the network after the quantization based on the network of FIG. The figure which shows the example of the shortest path network based on the network of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Route search apparatus 2 Input part 3 Data storage apparatus 4 Shortest path network data generation part 5 Storage device 6 Path search part 7 Output part 10,40 Path search network 20 Arc cost conversion network 30, 50 Shortest path network 40 'Path search network (After quantization)

Claims (8)

A data storage unit having a plurality of nodes, connecting adjacent nodes with arcs, and storing original route search network data in which a cost is set for each arc;
One of the plurality of nodes is set as a termination node, and the minimum cost of each path from each node to the termination node is calculated for all nodes including the termination node, and the calculated minimum cost and the data Based on the cost of each arc in the storage unit, the cost of each arc in the original route search network is converted, and the minimum cost path configured by only the arc whose converted cost is zero and the nodes connected by the arc. A network data generation unit for generating network data;
A network generation device for searching a total minimum cost route, comprising:   The network data generation unit includes a cost calculation unit that calculates the minimum cost, an arc cost conversion unit that converts a cost of each arc of the original route search network, the node stored in the data storage unit, and the node Arc deletion means for deleting arc data whose cost is not zero from arc cost conversion network data composed of an arc and the cost after conversion obtained by the arc cost conversion means, and from the arc cost conversion network data The all-minimum cost path search network generation device according to claim 1, wherein the minimum cost path network data is generated by deleting arc data whose cost is not zero. The arc cost conversion means includes Ctail as the minimum cost to the end node calculated by the minimum cost calculation means for the node that is the starting point of the arc that is the cost conversion target, and the node that is the end point of the arc that is the cost conversion target The minimum cost up to the end node calculated by the minimum cost calculation means is stored in the data storage unit as Chead, and the cost before conversion of the arc to be converted that connects the start node and the end node is Carc. For all arcs, the converted cost HCarc is calculated using the following formula:
HCarc = Chead + Carc-Ctail
The network generation device for searching for a total minimum cost route according to claim 2, wherein the network generation device calculates the minimum cost route according to claim 2.   The network data generation unit includes cost quantization means for quantizing the cost of each arc of the original route search network according to a predetermined rule, and after the cost quantization processing by the cost quantization means, the minimum cost The network generation device for searching for all minimum cost routes according to any one of claims 1 to 3, wherein the calculation processing is configured to be performed.   The network generation apparatus for searching for a minimum cost route according to any one of claims 1 to 4, wherein the arc cost type is any one of distance, time, and amount. It has a plurality of nodes, connects adjacent nodes with arcs, sets the cost for each arc, and terminates any one of the plurality of nodes of the original route search network data stored in advance Selecting as a node;
A minimum cost calculating step for calculating a minimum cost of each path from each node to the terminal node for all nodes including the terminal node selected in the selection step;
An arc cost conversion step of converting the cost of each arc of the original route search network based on each minimum cost calculated in the minimum cost calculation step and the cost of each arc in the data storage unit;
Arc data whose cost is not zero is deleted from arc cost conversion network data composed of nodes and arcs of the data storage unit and costs converted in the arc cost conversion step. A network data generation step for generating minimum cost path network data composed of only connected nodes;
A network generation method for searching a total minimum cost route, comprising: An input unit for inputting information on the start and end of the route search target;
A network data storage unit storing the minimum cost route network data generated by the network generation device for total minimum cost route search according to any one of claims 1 to 5;
A route search unit that searches for at least one or more routes between the start end and the end input by the input unit using a minimum cost route network constructed by the minimum cost route search network data of the network data storage unit; ,
An output unit that outputs route information searched by the route search unit and cost information of the route;
A route search device characterized by comprising the above.   5. The minimum cost route network data generated by the network generation device according to claim 4 is stored in the network data storage unit, and the original route search network between the start end and the end point is stored in the route search unit. The route search device according to claim 7, wherein at least one route having a cost close to the minimum cost can be searched.

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