/* An actor that outputs a scaled version of the input.
Copyright (c) 1998-2007 The Regents of the University of California.
All rights reserved.
Permission is hereby granted, without written agreement and without
license or royalty fees, to use, copy, modify, and distribute this
software and its documentation for any purpose, provided that the above
copyright notice and the following two paragraphs appear in all copies
of this software.
IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
ENHANCEMENTS, OR MODIFICATIONS.
PT_COPYRIGHT_VERSION_2
COPYRIGHTENDKEY
*/
package ptolemy.actor.lib;
import ptolemy.data.BooleanToken;
import ptolemy.data.Token;
import ptolemy.data.expr.Parameter;
import ptolemy.kernel.CompositeEntity;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.NameDuplicationException;
import ptolemy.kernel.util.Workspace;
//////////////////////////////////////////////////////////////////////////
//// Scale
/**
Produce an output token on each firing with a value that is
equal to a scaled version of the input. The actor is polymorphic
in that it can support any token type that supports multiplication
by the <i>factor</i> parameter. The output
type is constrained to be at least as general as both the input and the
<i>factor</i> parameter.
For data types where multiplication is not commutative (such
as matrices), whether the factor is multiplied on the left is controlled
by the <i>scaleOnLeft</i> parameter. Setting the parameter to true means
that the factor is multiplied on the left, and the input
on the right. Otherwise, the factor is multiplied on the right.
@author Edward A. Lee, Steve Neuendorffer
@version $Id$
@since Ptolemy II 0.3
@Pt.ProposedRating Yellow (eal)
@Pt.AcceptedRating Yellow (yuhong)
*/
public class Scale extends Transformer {
/** Construct an actor with the given container and name.
* @param container The container.
* @param name The name of this actor.
* @exception IllegalActionException If the actor cannot be contained
* by the proposed container.
* @exception NameDuplicationException If the container already has an
* actor with this name.
*/
public Scale(CompositeEntity container, String name)
throws NameDuplicationException, IllegalActionException {
super(container, name);
factor = new Parameter(this, "factor");
factor.setExpression("1");
scaleOnLeft = new Parameter(this, "scaleOnLeft");
scaleOnLeft.setExpression("true");
// set the type constraints.
output.setTypeAtLeast(input);
output.setTypeAtLeast(factor);
// icon
_attachText("_iconDescription", "<svg>\n"
+ "<polygon points=\"-30,-20 30,-4 30,4 -30,20\" "
+ "style=\"fill:white\"/>\n" + "</svg>\n");
}
///////////////////////////////////////////////////////////////////
//// ports and parameters ////
/** The factor.
* This parameter can contain any scalar token that supports
* multiplication. The default value of this parameter is the
* IntToken 1.
*/
public Parameter factor;
/** Multiply on the left.
* This parameter controls whether the scale factor is multiplied
* on the left. The default value is a boolean token of value true.
* Setting is to false will multiply the factor on the right.
*/
public Parameter scaleOnLeft;
///////////////////////////////////////////////////////////////////
//// public methods ////
/** Clone the actor into the specified workspace. This calls the
* base class and then sets the type constraints.
* @param workspace The workspace for the new object.
* @return A new actor.
* @exception CloneNotSupportedException If a derived class has
* an attribute that cannot be cloned.
*/
public Object clone(Workspace workspace) throws CloneNotSupportedException {
Scale newObject = (Scale) super.clone(workspace);
newObject.output.setTypeAtLeast(newObject.input);
newObject.output.setTypeAtLeast(newObject.factor);
return newObject;
}
/** Compute the product of the input and the <i>factor</i>.
* If there is no input, then produce no output.
* @exception IllegalActionException If there is no director.
*/
public void fire() throws IllegalActionException {
super.fire();
if (input.hasToken(0)) {
Token in = input.get(0);
Token factorToken = factor.getToken();
Token result;
if (((BooleanToken) scaleOnLeft.getToken()).booleanValue()) {
// Scale on the left.
result = factorToken.multiply(in);
} else {
// Scale on the right.
result = in.multiply(factorToken);
}
output.send(0, result);
}
}
}