You have a private transport (PrT) network, including stops from public transport (PuT), but these stops are isolated (means that they are not on links or nodes). How can automatically assign the stops on links?
One approach is to use the “Aggregation of isolated nodes” (choose nodes, then right mouse click). There you can choose, whether the stops (nodes) shall split the link or shall be placed on the link.
Depending on your task you might also want to look at the new PTV Visum 14 feature “PuT supply from PTV Visum” which allows you to bring the whole PuT supply (stops, lines, etc.) from one network into another network. You will find this function under “File > Import > PuT supply from PTV Visum”. Watch here a video from our colleague Manuel Galster about this feature.
Accessibility is an important factor in traffic planning. PTV Visum can graphically represent how accessible places in the network are, how large the catchment area for stops and lines is, for example, and what proportion of the inhabitants are connected to the traffic network, and how well.
In the following, we will present five display options for accessibility:
Is it possible to re-name links, nodes or zones, to release partly occupied numbering ranges? Yes, a new feature in Visum 14 offers for many network object classes the function "Renumbering":
-> (Right click to open the context menu) -> Renumbering (Screenshots 1-2)
Without this feature a model might run out of available IDs. The suggested value for the ID-offset when reading additively or when using model transfer files is always the highest existing ID+1. Thereby in many cases (particularly by using external identifiers for IDs), long IDs could develop which may cause overflows.
With Visum 14, reading a network additively offers a new conflict avoidance option, to renumber the IDs for multiple network object classes (Screenshot 3). The “offset” holds the count for the existing network objects, which are renumbered from 1, and this counting is continued for the new added objects.
A workaround for Visum 13 and older uses a script solution, which is available in our FAQs.
For anyone who still wants to perform any renumbering per COM: Visum 14 offers for many more network object classes as listed above the COM method “Renumber”.
When exporting or copying to Excel (by file or clipboard, of lists or matrices) number formats or number values are sometimes changed. Why?
This might be related to the setting for the decimal symbol as point or comma, which needs to be equal for both Visum and Excel:
In Visum this is a program setting:
How can I display a flow bundle as a percentage of link flows?
The result is displayed in Figure 4.
Often seen: A small network, created to test some functionality, to make a quick estimation or to contribute to a larger network. How to set it up smart and effectively?
This article describes a way to create a stable fundament for any network, fast and suitable for every place in the world.
A classic GIS application: How to colorize a map to ensure that neighbouring countries never share the same colour?
Transferred onto PTV Visum: How to colorize zones individually?
(see fig. 1)
To create such a map with PTV Visum, proceed this way:
Alternatively use the dialog "Edit classification: Change colours" and choose in the colour scale's dropdown menu the entry "Create qualitative scale for current number of classes". (see fig. 3)
The result is not perfect, but in case of neighbouring zones sharing the same colour, you only need to change the used attribute's value.
(see fig. 4)
How to set up a filter for a calendar day or time interval in the Timetable editor?
For this purpose, the line filter is very suitable:
PTV Visum uses area objects for zones, territories, POIs, main nodes, main zones and toll systems, and offers a comfortable editor for their closed polygons. Are you sure to know all really helpful features available?
In principle every new release is more demanding regarding memory. The aim is to get faster and getting faster more often is accompanied by an increase in memory consumption. When using multi core processors, data also has to be stored multiple times, for example. So what can you do to save memory or have more available memory?
The 3-GB-option of Windows XP is also possible for other operating systems. Operating systems can be configured to allocate more memory to applications.
In order to use the matrices cache of VISUM in the menu "Extras->Options->Files&protocols->Matrices" you activate the function “Activate swap file“. The “Maximum size of matrix data stored in RAM” should be as small as possible.
If you are working with many matrices but they are not needed immediately and at the same time, via the menu File->File properties “Lagged matrix data loading on demand” you can save memory. This setting is saved in the version file and will be executed when reading it the next time.
Several procedures require less memory if executed only with one CPU core (set under "Extras->Options->Environment").
The Digitize mode ( e.g. of zone borders) does not allow you to zoom across the toolbar or move display details. The relevant function is greyed out (Image 1). From PTV Visum 11.5, however, you will be able to catch the points of common areas.
If too many points are too close to each other, you'd normally first have to switch to the Zoom mode again (Image 2). But now you can also zoom using the mouse wheel. If you want the mouse pointer to be in the focus while zooming, keep the CTRL key held down while turning the mouse wheel. You can also use the Page up and Page down keys for zooming. Use the arrow keys if you want to move the network.
There are at least 3 ways to change all or all active attributes.
Every now and then we receive inquiries from users who find that the Python scripts they used successfully under PTV Visum 32-bit no longer work under PTV Visum 64-bit. In our experience the reason is in most cases that the script uses a Python library which is not yet available in a 64-bit version. Two typical cases are GDAL (for GIS functions) and tkinter (for graphical user interfaces). In the case of gdal we hope that the ongoing effort in the open source community will soon produce a stable 64-bit version, which we will then make available for PTV Visum. In the case of tkinter we urgently recommend that you implement the graphical user interface in wxPython instead. There is no indication that a 64-bit port of tkinter is forthcoming, and wxPython GUIs conform more closely to the Windows look and feel. All of the add-ins that come with PTV Visum now use wxPython. If you still observe error messages pointing to tkinter, it is an indication that your installation is not up to date and applying the latest service pack should fix the problem.
The middle mouse button or mouse wheel allow you to temporarily switch to "manual" mode.
The OD pair filter is fundamentally different from the network object filter, since it filters origin-destination pairs between zones and cannot be used to set network objects active or passive. In the graphic display and in lists, the OD pair filter has an effect on all volume skims.
You now have the option to switch off the recalculation of network volumes (see figure 1).
You can e.g. use the filter (without the recalculation function) for the following:
The "Difference network" allows you to compare two networks and show the differences between them.
If you want to add further network data to an existing network in PTV Visum, without losing the existing data, these can be read in additionally with the following steps:
Customers often ask us how GPS points in WGS84 can be imported in VISUM. The simplest way is, by saving a small network file and supplementing the point data by the column format NO;X-Coordinate;Y-Coordinate.
This is how it works:
(If the coordinate system is double-clicked, the projection dialogue is closed automatically.)
(Admittedly this is laborious. Did you know that in the dialogue, you can navigate using the arrow keys and activate or deactivate entries using the space bar?
Of course you can also save a layout and keep it for later.
Tip: Did you know, that a network file is also written, where only the buttons of the table are included? These can also be changed very easily with a text editor.
Exit the dialogue with OK.
and can be replaced by other rows with the same format. (image 2)
Attention: The number groups of this node should not overlap with the number groups of the nodes in the version file, to which these nodes are written.
In principle POI objects can be used instead of nodes, but in this case a POI category has to be created first. In the dialogue "Save network" activate the object type POIOFCAT_1 and the column format looks slightly different.
The contents of this network file can now be added to a version file:
Tip: The now read nodes can be displayed via the graphics parameter and filter their properties as isolated nodes. To do so, create a filter with the attribute NumLinks and the value range up to 0. (image 4)
This add-in allows you to visually inspect the surroundings of a network node or main node in Google Maps. This can be a handy shortcut, if you wish to check the correctness of the junction model.
The add-in calls up a satellite map of the surroundings of the node or main node in Google Maps and displays the result in your Web browser.
In order to convert the position of the node to latitude / longitude, Visum needs to know the projection used for the coordinates in your model. Be sure to set the projection under Network – Parameters before using the add-in. In some cases the third-party library used for the reprojection fails to convert from the Visum projection to lat/long. In those cases you can try switching manually (in Network – Parameters) to WGS_1984. Don’t forget to switch back when you are done, if you plan to save your changes.
The add-in assumes that you have a Web browser installed on your computer and it is set up as the default program for files with extension “.htm”. You also need a connection to the Internet while using the add-in.
Start by marking a single node or main node in the network editor.
Zoom level: A number describing how far Google maps should zoom in to the coordinates of the node. A level of 19 usually results in a view that is detailed enough to see lane markings etc. if present. Use a lower number if Google complains that it does not have maps down to this resolution, or if the coordinate match is less than perfect.
Click Display to show the map for the currently marked node or main node. The window will remain open, so you can mark and display further nodes. Click Close when done.
Since PTV Visum 11.02-02 on loading a version file, PTV Visum can optionally load any contained matrices on demand, i.e. leave their data in the version file until they are actually accessed.
This will speed up version file loading, especially if you do not need the matrices for what you are about to do with the model, for example only view volumes in the network.
Using this option, the time PTV Visum needs to read additional matrix data, does not effect the performance.
In order to benefit from deferred loading you need to activate this behaviour per version file:
The effect with version files holding numerous, large matrices might reduce the loading time up to 90%.
Easily forgotten and overlooked, but extremely powerful and helpful the "Check network" feature (Calculate menu) in Visum.
You can use it to check for mistakes or weak spots in the network. The results of the check are written to a file that you can view directly in PTV Visum. It is convenient that after the check you can fix the problem immediately or quickly check "suspicious" network elements by setting them active. All other network elements become passive, thus enabling you to highlight these network elements graphically or list these seperately.