Add files via upload

Author: vlarmet

readme.Rmd

@@ -18,6 +18,7 @@ For now, `cppRouting` can implement :
   - uni-directional Dijkstra algorithm,
   - bi-directional Dijkstra algorithm,
   - uni-directional A* algorithm  
+  - New bi-directional A* algorithm (Piljs & Post, 2009 : see http://repub.eur.nl/pub/16100/ei2009-10.pdf)
 
 All these functions are written in C++ and use std::priority_queue container from the Standard Template Library.  
 This package have been made with `Rcpp` and `parallel` packages.
@@ -52,12 +53,10 @@ Data has to be a 3 columns data.frame or matrix containing from, to and a cost/d
 - Isochrones/isodistances with one or multiple breaks.  
 
 The choice between all the algorithms is available for `get_distance_pair` and `get_path_pair`. In these functions, uni-directional Dijkstra algorithm is stopped when the destination node is reached.  
-A* is relevant if geographic coordinates of all nodes are provided. Note that coordinates should be expressed in a projection system.  
-To be accurate and efficient, `A*` algorithm should use an admissible heuristic function (here the Euclidean distance), e.g cost and heuristic function must be expressed in the same unit.  
-In `cppRouting`, heuristic function `h` is defined such that : h(xi,yi,xdestination,ydestination)/k, with a constant k; so in the case where coordinates are expressed in meters and cost is expressed in time, k is the maximum speed allowed on the road.  
+`A*` and `NBA*` are relevant if geographic coordinates of all nodes are provided. Note that coordinates should be expressed in a projection system.  
+To be accurate and efficient, `A*` and `NBA*` algorithms should use an admissible heuristic function (here the Euclidean distance), e.g cost and heuristic function must be expressed in the same unit.  
+In `cppRouting`, heuristic function `h` is defined such that : h(xi,yi,xdestination,ydestination)/k, with a constant k; so in the case where coordinates are expressed in meters and cost is expressed in time, k is the maximum speed allowed on the road. By default, constant is 1 and is designed for graphs with cost expressed in the same unit than coordinates (e.g meters).  
 
-By default, constant is 1 and is designed for graphs with cost expressed in the same unit than coordinates (e.g meters).  
-
 If coordinates cannot be provided, bi-directional Dijkstra algorithm can offer a good alternative to A* in terms of performance.
 
 ##Examples
@@ -106,11 +105,6 @@ system.time(
 pair_dijkstra<-get_distance_pair(graph,origin,destination)
 )
 
-#Parallel
-system.time(
-pair_dijkstra_par<-get_distance_pair(graph,origin,destination,allcores = TRUE)
-)
-
 ```
 ####Using bi-directional Dijkstra algorithm
 ```{r,}
@@ -119,11 +113,6 @@ system.time(
 pair_bidijkstra<-get_distance_pair(graph,origin,destination,algorithm = "bi")
 )
 
-#Parallel
-system.time(
-pair_bidijkstra_par<-get_distance_pair(graph,origin,destination,algorithm = "bi",allcores = TRUE)
-)
-
 ```
 ####Using A* algorithm
 Coordinates are defined in meters and max speed is 110km/h; so for the heuristic function to be admissible, the constant equal 110/0.06 :  
@@ -133,17 +122,21 @@ system.time(
 pair_astar<-get_distance_pair(graph,origin,destination,algorithm = "A*",constant = 110/0.06)
 )
 
-#Parallel
+```
+####Using NBA* algorithm
+```{r,echo=TRUE}
+#NBA* single node
 system.time(
-pair_astar_par<-get_distance_pair(graph,origin,destination,algorithm = "A*",constant = 110/0.06,allcores = TRUE)
+pair_nba<-get_distance_pair(graph,origin,destination,algorithm = "NBA",constant = 110/0.06)
 )
-```
 
-####Output  
-                  
+```
+####Output
 ```{r,echo=TRUE}
-head(cbind(pair_dijkstra,pair_bidijkstra,pair_astar,pair_dijkstra_par,pair_bidijkstra_par,pair_astar_par))
+head(cbind(pair_dijkstra,pair_bidijkstra,pair_astar,pair_nba))
+
 ```
+#####In `get_distance_pair` function, all the algorithms can be ran in parallel by setting TRUE to allcores argument.  
 
 
 ###Compute isochrones
@@ -344,7 +337,7 @@ test_dodgr<-dodgr_paths(graph=data.frame(roads2),from=origin,to=destination,pair
 
 #cppRouting
 system.time(
-test_cpp<-get_path_pair(graph,origin,destination,algorithm = "A*",constant=110/0.06)
+test_cpp<-get_path_pair(graph,origin,destination,algorithm = "NBA",constant=110/0.06)
 )
 ```
 ###Test similarity of the first travel

readme.md

@@ -11,6 +11,7 @@ Package presentation
 -   uni-directional Dijkstra algorithm,
 -   bi-directional Dijkstra algorithm,
 -   uni-directional A\* algorithm
+-   New bi-directional A\* algorithm (Piljs & Post, 2009 : see <http://repub.eur.nl/pub/16100/ei2009-10.pdf>)
 
 All these functions are written in C++ and use std::priority\_queue container from the Standard Template Library.
 This package have been made with `Rcpp` and `parallel` packages.
@@ -50,11 +51,9 @@ Main functions
 - Isochrones/isodistances with one or multiple breaks.
 
 The choice between all the algorithms is available for `get_distance_pair` and `get_path_pair`. In these functions, uni-directional Dijkstra algorithm is stopped when the destination node is reached.
-A\* is relevant if geographic coordinates of all nodes are provided. Note that coordinates should be expressed in a projection system.
-To be accurate and efficient, `A*` algorithm should use an admissible heuristic function (here the Euclidean distance), e.g cost and heuristic function must be expressed in the same unit.
-In `cppRouting`, heuristic function `h` is defined such that : h(xi,yi,xdestination,ydestination)/k, with a constant k; so in the case where coordinates are expressed in meters and cost is expressed in time, k is the maximum speed allowed on the road.
-
-By default, constant is 1 and is designed for graphs with cost expressed in the same unit than coordinates (e.g meters).
+`A*` and `NBA*` are relevant if geographic coordinates of all nodes are provided. Note that coordinates should be expressed in a projection system.
+To be accurate and efficient, `A*` and `NBA*` algorithms should use an admissible heuristic function (here the Euclidean distance), e.g cost and heuristic function must be expressed in the same unit.
+In `cppRouting`, heuristic function `h` is defined such that : h(xi,yi,xdestination,ydestination)/k, with a constant k; so in the case where coordinates are expressed in meters and cost is expressed in time, k is the maximum speed allowed on the road. By default, constant is 1 and is designed for graphs with cost expressed in the same unit than coordinates (e.g meters).
 
 If coordinates cannot be provided, bi-directional Dijkstra algorithm can offer a good alternative to A\* in terms of performance.
 
@@ -132,19 +131,7 @@ pair_dijkstra<-get_distance_pair(graph,origin,destination)
     ## Running Dijkstra ...
 
     ##    user  system elapsed 
-    ##   58.44    0.71   59.50
-
-``` r
-#Parallel
-system.time(
-pair_dijkstra_par<-get_distance_pair(graph,origin,destination,allcores = TRUE)
-)
-```
-
-    ## Running Dijkstra ...
-
-    ##    user  system elapsed 
-    ##    0.11    0.02   21.95
+    ##   61.37    0.73   63.01
 
 #### Using bi-directional Dijkstra algorithm
 
@@ -158,19 +145,7 @@ pair_bidijkstra<-get_distance_pair(graph,origin,destination,algorithm = "bi")
     ## Running bidirectional Dijkstra...
 
     ##    user  system elapsed 
-    ##   37.34    1.42   38.78
-
-``` r
-#Parallel
-system.time(
-pair_bidijkstra_par<-get_distance_pair(graph,origin,destination,algorithm = "bi",allcores = TRUE)
-)
-```
-
-    ## Running bidirectional Dijkstra...
-
-    ##    user  system elapsed 
-    ##    0.07    0.01   16.41
+    ##   38.85    0.99   39.87
 
 #### Using A\* algorithm
 
@@ -186,40 +161,37 @@ pair_astar<-get_distance_pair(graph,origin,destination,algorithm = "A*",constant
     ## Running A* ...
 
     ##    user  system elapsed 
-    ##   30.90    1.66   32.59
+    ##   32.45    2.01   34.51
+
+#### Using NBA\* algorithm
 
 ``` r
-#Parallel
+#NBA* single node
 system.time(
-pair_astar_par<-get_distance_pair(graph,origin,destination,algorithm = "A*",constant = 110/0.06,allcores = TRUE)
+pair_nba<-get_distance_pair(graph,origin,destination,algorithm = "NBA",constant = 110/0.06)
 )
 ```
 
-    ## Running A* ...
+    ## Running NBA* ...
 
     ##    user  system elapsed 
-    ##    0.16    0.01   15.08
+    ##   18.61    2.78   21.45
 
 #### Output
 
 ``` r
-head(cbind(pair_dijkstra,pair_bidijkstra,pair_astar,pair_dijkstra_par,pair_bidijkstra_par,pair_astar_par))
+head(cbind(pair_dijkstra,pair_bidijkstra,pair_astar,pair_nba))
 ```
 
-    ##      pair_dijkstra pair_bidijkstra pair_astar pair_dijkstra_par
-    ## [1,]      78.82095        78.82095   78.82095          78.82095
-    ## [2,]     306.31827       306.31827  306.31827         306.31827
-    ## [3,]     487.43158       487.43158  487.43158         487.43158
-    ## [4,]     106.58475       106.58475  106.58475         106.58475
-    ## [5,]     209.21585       209.21585  209.21585         209.21585
-    ## [6,]     355.96210       355.96210  355.96210         355.96210
-    ##      pair_bidijkstra_par pair_astar_par
-    ## [1,]            78.82095       78.82095
-    ## [2,]           306.31827      306.31827
-    ## [3,]           487.43158      487.43158
-    ## [4,]           106.58475      106.58475
-    ## [5,]           209.21585      209.21585
-    ## [6,]           355.96210      355.96210
+    ##      pair_dijkstra pair_bidijkstra pair_astar pair_nba
+    ## [1,]      475.9349        475.9349   475.9349 475.9349
+    ## [2,]      502.9290        502.9290   502.9290 502.9290
+    ## [3,]      512.4824        512.4824   512.4824 512.4824
+    ## [4,]      246.4425        246.4425   246.4425 246.4425
+    ## [5,]      776.0014        776.0014   776.0014 776.0014
+    ## [6,]      109.4739        109.4739   109.4739 109.4739
+
+##### In `get_distance_pair` function, all the algorithms can be ran in parallel by setting TRUE to allcores argument.
 
 ### Compute isochrones
 
@@ -257,7 +229,7 @@ p<-ggmap(dijon)+
 p
 ```
 
-![](readme_files/figure-markdown_github/unnamed-chunk-7-1.png)
+![](readme_files/figure-markdown_github/unnamed-chunk-8-1.png)
 
 Applications
 ============
@@ -319,7 +291,7 @@ p<-ggplot()+
 p
 ```
 
-![](readme_files/figure-markdown_github/unnamed-chunk-10-1.png)
+![](readme_files/figure-markdown_github/unnamed-chunk-11-1.png)
 
 Application 2 : Calculate the minimum travel time to the closest maternity ward in France
 -----------------------------------------------------------------------------------------
@@ -361,7 +333,7 @@ p<-ggplot()+
 p
 ```
 
-![](readme_files/figure-markdown_github/unnamed-chunk-13-1.png)
+![](readme_files/figure-markdown_github/unnamed-chunk-14-1.png)
 
 Benchmark with other R packages
 ===============================
@@ -388,7 +360,7 @@ system.time(
 ```
 
     ##    user  system elapsed 
-    ##   85.69    0.06   85.76
+    ##   84.08    0.03   84.26
 
 ``` r
 #dodgr
@@ -409,7 +381,7 @@ test_dodgr<-dodgr_dists(graph=data.frame(roads2),from=origin,to=destination,para
 ```
 
     ##    user  system elapsed 
-    ##   84.42    0.03   84.59
+    ##   83.94    0.08   84.15
 
 ``` r
 #cppRouting
@@ -419,7 +391,7 @@ test_cpp<-get_distance_matrix(graph,origin,destination,allcores = FALSE)
 ```
 
     ##    user  system elapsed 
-    ##   57.71    0.56   58.28
+    ##   57.52    0.35   57.92
 
 #### Ouput
 
@@ -428,12 +400,12 @@ head(cbind(test_igraph[,1],test_dodgr[,1],test_cpp[,1]))
 ```
 
     ##            [,1]     [,2]     [,3]
-    ## 115900 503.3265 503.3265 503.3265
-    ## 122467 406.0058 406.0058 406.0058
-    ## 228275 338.3132 338.3132 338.3132
-    ## 33061  266.5725 266.5725 266.5725
-    ## 30412  151.0826 151.0826 151.0826
-    ## 208187 436.1984 436.1984 436.1984
+    ## 158924 453.1183 453.1183 453.1183
+    ## 208013 485.0933 485.0933 485.0933
+    ## 51666  203.5290 203.5290 203.5290
+    ## 77929  241.8183 241.8183 241.8183
+    ## 114669 391.8915 391.8915 391.8915
+    ## 74916  669.7842 669.7842 669.7842
 
 ### Distance matrix : parallel
 
@@ -445,7 +417,7 @@ test_dodgr<-dodgr_dists(graph=data.frame(roads2),from=origin,to=destination,para
 ```
 
     ##    user  system elapsed 
-    ##  119.76    0.75   31.66
+    ##  118.12    0.43   31.02
 
 ``` r
 #cppRouting
@@ -455,7 +427,7 @@ test_cpp<-get_distance_matrix(graph,origin,destination,allcores = TRUE)
 ```
 
     ##    user  system elapsed 
-    ##    0.13    0.03   21.95
+    ##    0.15    0.08   21.52
 
 Benchmark on computing shortest paths by pairs
 ----------------------------------------------
@@ -471,19 +443,19 @@ test_dodgr<-dodgr_paths(graph=data.frame(roads2),from=origin,to=destination,pair
 ```
 
     ##    user  system elapsed 
-    ##  528.75   18.74  548.89
+    ##  522.81   18.75  542.18
 
 ``` r
 #cppRouting
 system.time(
-test_cpp<-get_path_pair(graph,origin,destination,algorithm = "A*",constant=110/0.06)
+test_cpp<-get_path_pair(graph,origin,destination,algorithm = "NBA",constant=110/0.06)
 )
 ```
 
-    ## Running A* ...
+    ## Running NBA* ...
 
     ##    user  system elapsed 
-    ##    7.81    0.06    7.95
+    ##    5.00    0.34    5.34
 
 ### Test similarity of the first travel
 
@@ -492,13 +464,13 @@ test_cpp<-get_path_pair(graph,origin,destination,algorithm = "A*",constant=110/0
 length(test_dodgr[[1]][[1]])
 ```
 
-    ## [1] 204
+    ## [1] 130
 
 ``` r
 length(test_cpp[[1]])
 ```
 
-    ## [1] 204
+    ## [1] 130
 
 ``` r
 #Setdiff