Archived News 2004
September 2004
5.4a Changes
Version 5.4a completes the ability to create control panels with PLE and also corrects a number of minor problems.
View>Rescale has replaced the old View>X Rescale and View>Y Rescale and provides more choices for adjusting size including the adjustment of word sizes and all positions both horizontally and vertically. The Rescale dialog allows you to select scales. See Chapter 5 of the Reference Manual for more details.
Note that when moving from one computer to another you may be asked if you want to rescale views – this can be helpful for maintaining word wraps.
5.4 Changes
The most significant changes in Version 5.4 relate to Vensim PLE which has had Input Output objects added (see Chapter 12 of the User’s Guide) and Vensim PLE and PLE Plus which now both have the ability to override variable behavior during SyntheSim (see Chapter 13 of the User’s Guide).
Vensim PLE Plus has also had two new analysis tools added to help analyze Sensitivity Simulations. The first is the Sensitivity Graph tool configured to display individual traces, and the second is the Bar Graph tool configured to display histograms across simulations at special time. These should improve the ability to analyze sensitivity simulations.
The majority of remaining changes in 5.4 are bug fixes related to model resume, data equations, ODBC connections to SQL Server and problems with the variable rename function.
In Vensim DSS Only the Venapp command
TIMEAXIS>TIMEBASE|timebasename
Has been added to allow you to set the time base that will be used for graph display and also for interpreting the @ time when fetching variable values.
5.3a Changes
NOTE: All documentation for Vensim 5 is available online and can also be accessed from our website. On the Macintosh the documentation is installed separately and can be opened in a web browser.
Online Forum and Version Checking (not Macintosh)
Two commands have been added to the Help menu. Help>Online Forum takes you to an online forum in which you can post queries about Vensim and dynamic modeling in general. The forums can be read by anyone but you will need to create a user name and log in to actually post things. The second command Help>Newer Releases checks to see if the version of Vensim you are using is the most current. Both of these commands work by opening the default web browser and you will need an active connection to the internet to use them. Neither sends any information beyond the current Version number of the copy of Vensim you are using.
Modifying Variable Names
A new menu item Edit>Modify Names has been added to the menu that will allow you to globally change variable names by substituting strings within them. This can be useful after a copy and paste operation in order to line up variable names more closely with their intended representation.
Windows Explorer Behavior (not Macintosh)
Vensim has been modified so that when you click on a model in Windows Explorer with Vensim already open, that model is open in the current instance of Vensim rather than a new instance. You can still open a second instance of Vensim if you like by selecting it from the Start menu.
WIP Graphs (Not PLE)
The automatic display of Work in Progress graphs is now optional, and off by default. To enable display check "Open WIP Graph on Sim" on the Graphs tab of the Control Panel. If you have embedded a WIP graph in a sketch it will continue to display during simulation. It is only the creation of new graph windows when there are no embedded WIP graphs that is prevented.
Equation Editor Navigation (Standard, Pro and DSS only) A previous button <-- has been added to the navigation buttons on the Equation Editor. This is useful to return to the equation you were last editing after going to a new equation with Hilite or Sel… (renamed from Choose).
Undefined Subscripts (Pro and DSS only) When subscripted variables contain some elements that are not defined those elements will not have values. By default the analysis tools will display the names of the subscript elements, but no values. If you would like to suppress this and only see those subscript combinations that are defined check the "Skip Undefined" checkbox at the bottom of the subscript control. Note that if none of the currently selected subscripts elements are defined this may result in the display of a subscript combination that is not selected.
Editing Subranges (Pro and DSS only) There is not a button on the Full version of the subscript control (Click on "Full" on the Subscript Control dialog) that will allow you to go to the editor for a Subrange. Just click on the Subrange and then click on the "---" button to edit.
Command Changes - DSS Only
A number of commands have been added to make it easier to work with Sketches in Venapps
SKETCH>SHOWBEHAVIOR|skid|1 or 0
Turn on and off the display of behavior on the sketch. Note that when SyntheSim is active this will have no immediate effect since behavior is always shown in SyntheSim mode.
SKETCH>SHOWHIDDEN|skid|n + or –
Change the level to which to show hidden elements. You can use + and – to increase or decrease it, or specify the level as a number.
SKETCH>SYNTHVISIBLE|skid|O
After entering SyntheSim mode you can specify that you want to restrict the simulation to the variables currently visible in the sketch. Combining this with SHOWHIDDEN allows you to demonstrate the impact of adding structure.
SKETCH>RUNVISIBLE|skid|O
This command is used in place of MENU>RUN when you want to restrict the simulation to variables currently visible on the sketch. Similar to SKETCH>SYNTHVISIBLE but for non SyntheSim simulations.
The above commands work with the Vensim DLL and the MSVC60 example has been modified to show this. Even if you do not have a C compiler you can run VenMFC.exe in the MSVC60 subdirectory of the DLL directory to see how this looks.
5.3 Changes
NOTE: All documentation for Vensim 5 is available online and can also be accessed from the Vensim website. On the Macintosh the documentation is installed separately and can be opened in a web browser.
Hiding, Layered Presentations and Simulation (Not PLE or PLE Plus)
The number of depths that variables can be hidden to has been increased to 16. The up and down arrow keys can be used to change the current hide depth being shown. When the Magic Wand is selected the depths change one at a time. If the other tools are selected, however, the depths will change so that there is a visible difference (if nothing is hidden they will just toggle between Hide/Show).
To create a layered presentation use the down arrow to hide things, then click on the Hiding Magic want and use the up arrow to go to hide level 16. Click on the last things you want to disappear, click on the up arrow to move to hide level 15 and click on the second last things you want to disappear and so on. Once you have finished click on the Lock tool and then the up and down arrow keys will move through the layered presentation skipping the extra hide levels in between.
You can also cause Vensim to simulate only the structure that is currently visible. This is done with the menu item Models>Partial Simulation>Visible variables. In SyntheSim mode this will cause SyntheSim to be performed only on the subset of the model currently visible. The up and down arrow keys can then be used to expose structure and, simultaneously, indicate the behavior change that results from the additional structure. You can also use this as a method to make more or fewer sliders available for adjustment.
Note that restricting simulation to visible variables means that any variable not defined on the current View will be held at its initial value. This includes Shadow variables. This is a convenient way to isolate behavior to the structure you are currently working with, but may require some reorganization of View contents to convey your message.
Sensitivity Simulations (Not PLE)
Two new options have been added to sensitivity simulations. The first, “Latin Grid” does a grid search other the probabilistic distribution of the various parameters. This is much like running a multivariate vector search but allows for non-uniform distributions of parameters so that the parameter space is sampled more coarsely in the probability tails.
The second, “File” allows you to specify a file of constant changes. This file must be tab delimited with a list of constants across the top and the values in the lines that follow. The simulations will continue through the end of the file. This allows you to use any parameter drawings you desire as inputs to the sensitivity analysis.
Cut and Paste (Not PLE or PLE Plus)
When pasting structure you can now specify a prefix and suffix that will be used when renaming variables. This, allows, for example, the use of sector names to keep variables coherently named and can remove some of the tedium of renaming the variables that would have ended in 0, 1 and so on. If, after using the prefix and suffix the variable name is still not unique Vensim will continue to add the numeric suffixes.
Navigation Controls (Not PLE)
The navigation links have been generalized to allow you to switch models, open other files and access web sites in addition to moving around within a model. Vensim recognizes several file types so that opening a .mdl or .vmf file will open the model, a .vdf file will set the run name and start a simulation, a .cin file will read in changes, a .vgd or .vgf file will load the graph definitions, while .vts and .sts files will load the toolsets.
(Not Macintosh) For other file types Vensim will pass the information to the system Shell and attempt to open the file based on association. For example a .xls file would normally be opened with Excel. To open a web site just enter the full address (http://www.vensim.com for example) and clicking on the navigation link will cause the default browser to open at that web location.
(DSS Only) For external files, this functionality is available inside a Venapp using the FILE>SHELL|fileorwebsite command. For internal file types there are already commands to do the various things. Referring to a .html file can be used as an alternative to the SPECIAL>WINHELP command.
Export Formats
A Data List format has been added for exporting. This creates a tab delimited file with data in the format
Variable Time Value
or, if you select to show subscripts in columns,
Variable Sub1 Sub2 Sub3 Time Value
This format makes it easier to read the data into databases and also to create Pivot tables. To get the data list format just select it in the export control dialog or, as a command use VDF2DLIST. The default extension on the file created is.txt.
Suppressing Sliders in SyntheSim
If you set the minimum and maximum equal for the range of a constant in the equation editor no slider will be created for that constant in SyntheSim mode.
Graph Definitions
The keyword NO-LEGEND now works with bar graphs to suppress the legend, title or bar labels.
Escape Sequences and Far-Eastern Characters
In addition to using " to represent double quotes in variable names you can now use for a backslash and _ for a hard undebar _. A backslash by itself will also appear as a backslash unless it is followed by a " or _. These changes will prevent some problems that occur with double byte character sets.
If you are using a double byte character set be sure to check the option in Model>Settings>Sketch. Note that some variable names may appear incorrectly in the equation editor because of the use of escape sequences. Do not change these names in the equation editor; they should appear fine in the sketch and on output.
An option has also been added there to use hard underbars. Normally Vensim treats underbars and spaces as the same thing. If you want one or more explicit underbars in a variable name, check this option on the Model>Settings>Sketch dialog and then create or change the variable name. This setting only influences editing, it does not have any effect on the existing model.
Tool Font Face (PLE and PLE Plus)
You can now set Font Face to be used in tools (and the default Sketch Font Face) from the Options>Options dialog. This is useful is you prefer something different from Times New Roman, or if you need a face that will consistently display information (for example a Cyrillic font).
New £ prices have been released for all Vensim products due to changes in the exchange rate of the £ against the $. Euro prices for Vensim, Sable and RightChoice products have also changed as a result of currency fluctuations.