The workflow for for model development, debugging and analysis in Magnolia is relatively simple.  The following steps summarize the tasks involved in creating and running a Magnolia model.

Creating and Opening a Model

A new model can be created by selecting “File -> New -> CSL Model” from the main menu or toolbar.  A skeleton CSL file (shown below) will be displayed in a code editor, which can then be edited.  Alternatively, an existing model can be opened using either the appropriate main menu/toolbar buttons, or by navigating the filesystem in the browser window and double-clicking the desired file.  The model will be built upon loading; and errors in the model will be displayed in the alerts window and command window after the model is loaded.

A detailed explanation of CSL syntax is presented in the "Modeling Language Overview" and "CSL Language Reference" sections.

! Magnolia CSL model file
model Model_1


    ! The INITIAL section contains statements which are evaluated
    ! once at the beginning of the simulation run

end ! initial


    ! The DYNAMIC section contains statements which are evaluated
    ! at each output time point


        ! The DERIVATIVE section contains statements which are
        ! used to compute derivatives

        ! Example: exponential decay
        constant k   = 1.0  ! Decay rate constant
        constant xic = 10.0 ! Initial condition
        xd = -k*x           ! Derivative
        x  = integ(xd, xic) ! Integrate derivative to compute state

        constant tstop = 10.0
        termt(t >= tstop, 'Stopped on time limit')

    end ! derivative

    discrete DISCRETE_1

        ! DISCRETE sections contain statements which are only
        ! evaluated at specific time points.  A model
        ! can contain an arbitrary number of DISCRETE sections.

    end ! DISCRETE_1

end ! dynamic


    ! The TERMINAL section contains statements which are evaluated
    ! once at the conclusion of the simulation run

end ! program

Building the Model

The model is built (translated and compiled) both when it is opened, and when it is executed.  This process happens quickly even for large files.  A small “wait” dialog is show during this process, but this dialog may be visible for only a fraction of a second.