# Archive for category: Dymola commands

## Handling trajectory files and utilising simulation results within Dymola

Many engineering problems require the results of one simulation to influence the inputs into a second simulation; in effect, a preliminary simulation is used to calibrate a second simulation. This could be done manually, but it makes more sense to automate the process wherever possible. With a little knowledge...

## Using the Onboard Eigenvalue Function

This article introduces the use of the Dymola function for calculating eigenvalues, with syntax, inputs and interpretation of outputs. It’s also intended to present some examples of diagrams produced in the software that can provide insight into linear systems, and explain a little about what eigenvectors and their eigenvalues...

## Directories, Folders & Files From Dymola

Using & Creating Directories The working directory is the location on the computer in which Dymola runs and writes various files and of course the output file containing relevant trajectories of variables. It’s possible to find out, or alter which directory this is at some point during a simulation...

## Using DynamicSelect in Icons

DynamicSelect is a feature which allows the user to dynamically change aspects of the model during simulation. The function syntax is as follows: name of graphical feature = DynamicSelect (editing state, dynamic state)   Where any graphical feature, such as coordinates, colour, text, etc., in graphical annotations can be...

## The Dymola Save Total Option

Save Total provides a way to create a single file describing a class with all depended classes included. This is useful when you want to send someone the model without having to provide them with the full libraries being utilized by the library. Save Total Tool Note that encrypted...

## Plotting parametric curves

There is a new function, called plotParametricCurve, which plots curves defined by a parameter and can be used in the command window: An example will help to understand how this function works: 1.    Go to the command window and enter the following vectors: s = 0 : 0.1 :...

## Selection of variables to be saved in the result file

One of the most useful features of Dymola 2013 FD01 is a new annotation that enables the selection of a set of variables and / or parameters to be saved in the result file. Hence, the post-processing of simulations with large result files is improved, as users don’t have...

## Plotting general expressions

Dymola 2013 FD01 has the ability to create and plot a general expression through the context menu of a signal in a plot window. 1. Right-click on a plot window and select Plot Expression (you can also go to the Plot menu in the Dymola toolbar and then click...

## Adding signal operations to plots

Besides plotting general expressions, Dymola 2013 FD01 allows the user a straightforward calculation of several relevant magnitudes in a plot window. To select this, right-click on a plotted signal and select Signal Operators. A menu will be displayed with the following list of applicable operators, which can be used...