Map and Nod use graphs, made of nodes and arcs to model transport networks. These graphs are stored under the form of two data files, one for the nodes, their co-ordinates and their name, the other containing the arcs, with the means of transport and the duration and/or the number of kilometres. Some examples are available from here.
After having established on your computer the necessary architecture of the directories, launch Map then click in the menu Fichiers, Fichiers du graphe, and indicate successively the file of the nodes and file of the arcs. They are then read by Map.
Then go in the menu Image and click on Zoom curseur. Click in the zone of image to see the nodes of the graph. When the zoom cursor is activated (a cross replaces the usual arrow of the mouse) a click on the image identifies the node nearest to the selected point. The co-ordinates of the nodes are recomputed so that the selected node is found in the centre of the image and a coefficient of zoom is applied. The right button of the mouse makes it possible to increase, while the left button makes it possible to decrease the size of the zoom. By maintaining the Ctrl key pressed one increases the coefficient of the zoom.
For the use of Map, it is necessary to create on its computer the following architecture of directories:
To be able to save images, in bitmap or vectorial formatds, it is necessary to place an unspecified file in the repertory c:\data\cartes\images \.
For a correct reading of the data files, the separator of decimals of the computer must be set on the character point ("."). to carry out this setting, go in the Start menu, Parameters, Control panel, then click on the regional Parameters. In the Numbers section, it should be indicated that the symbol of the decimals is the point ("."). By default the French setting considers the comma as being the separator of decimal.
Before starting to digitize, it is better to start from a file of nodes containing two nodes (at least) selected so as to constitute the longest possible diagonal and whose co-ordinates X and Y have for unit the kilometre. The co-ordinates of the two selected nodes must be given carefully so that the chock is precise. It is also necessary to define identifying code for of the two nodes which must be numerical and count at the maximum 10 character. This operation must be made in a text editor (notepad for example) starting from a file of existing nodes.
To digitalize a graph in Map, it is necessary to have a scanned image (with the formats bmp, JPEG or GIF) of the space which one wants to digitalize. To be able to work effectively, it is recommended to attenuate the intensity of the image so that the graph is well detached in the foreground.
Note: the size of the image is limited only by the capacity of your computer, but it can prove to be necessary to increase the image zone which is not automatically redimensioned when the background image is charged. For that to go in menu Image then Zoom et parametres d’affichage.
In the menu Image the sub-menu Charge une image en fond makes it possible to choose the file to be visualized in the background of the screen, then to digitalize nodes. It is asked to position two nodes according to the longest possible diagonal to fix the graph. For that it is necessary to click two successive times while entering each time the name and especially the code of the nodes concerned. Then, with the next click, Map carries out the adjustment of the screen coordinates of the nodes.
One digitizes new nodes starting from the floating box of edition of the nodes which one opens starting from menu Noeuds , then Modification des noeuds. Once the box of modification of the nodes opened, a click of the left button edits the closest existing nodes, while a click on the right button proposes to create a new node. In the case of a creation, it is necessary to indicate a name and moreover an identifying code.
Menu Fichiers, Fichiers du graphe...
To modify the zoom parameters:
To visualize the graph:
Menu Fichiers, Ouvrir...
Check the valuation (time or kilometres)
Fill the matrix of minimal arcs: menu Arcs, Création matrice... (procedure launched automatically on the last version of NOD)
Then it is possible to calculate the minimum path:
To edit a file of results:
To edit a graph (see here)
Select a file of the node-value type: menu Fichier, Fichier du type noeud-valeur, Numéro 1... (ignore the error message about the file number 2)
Then define the classes: menu Fichiers, Statistiques...
To define the number of classes (from 1 to 10), choose the limits (Iso-amplitude, Iso-population, with regular interval or manually by clicking in the boxes of each class) and choose the colours.
In MAP to visualize the accessibility measurements, menu Noeuds, Affiche sur les noeuds, La valeur 1...
To create a vectorial image, select the vectorial mode (menu Image, Image vectorielle) then save the image (menu Image, Enregistre l’image)