Skip to content

Resonance Model Object

Description

Returns a 'single-point object whose modes frequencies, loss coefficients and amplitude vector are set to the values of a model of resonance defined in a plain text file.

(make-object 'reson-model ... )

Lisp Syntax and Default Values

A 'reson-model object can be created using the following Lisp syntax:

(make-object 'reson-model reson_file_name)

Parameters

The 'reson-model object is a single point and consequently does not have any physical properties, but takes a text file from which it reads frequency data directly:

  • reson_file_name: A character string containing the name of a model of resonance file.

To specify the path address of the file, you have to follow the syntax rules of your operating system. As there is no default value for the file name, a "wrong number of arguments" error will be displayed if a resonance file name is not provided. Relative file paths (i.e. not absolute paths, which start with the root directory) are relative to the Modlays application, and must be given as a character string - in double quotes as in the following example:

(make-object 'reson-model "Examples/analysis/resonance/rclotmi.txt")

Accesses

A 'reson-model object can be only accessed in the 'normal direction:

(make-access my-reson-model my-controller 'normal)
Since a 'reson-model object does not have spatial information, my-controller should be a constant between 0 and 1. In fact, any position (even a time-varying position) can be used, but it will not influence the object motion. The position controller is necessary for keeping compatibility with other Modalys objects.

Options

Resonance Model File Format

The model of resonance file must be a plain text file with the ".txt" extension and has to be written with one set of resonance data per line, with values separated by tabs or spaces, in the following format:

     <index> <freq> <amp> <bandwidth>

For example:

      1 4.65239 -55.16879 .2261643

     2 16.21073 -66.87767 .5535431

     3 19.23595 -67.9138 .06310855

     4 20.29903 -47.72019 .4553944

     5 24.42205 -55.92316 .1438602

The frequencies and bandwidths must be in Hz. The amplitudes must have a linear scale representation.

As with Modalys scripts, lines beginning with a semi-colon are used for comments and ignored.

This format is the standard text-based format for IRCAM's modres analysis. Analyses saved to .sdif files should be converted to a text file representation.