package affectors;

import main.Node;
import main.Globals;

/** This is the standard affector for decay of a Node.  Use this for both intracellular
extracellular nodes. Each Node should have one of these unless its concentration is supposed
to stay completely fixed over time (for instance, some input that is external to the network
you're modeling).

<p> <b>Formula</b>
<br>dnodex/dt = -nodex / H_nodex

<p> <b>Parameters</b>
<table width="500" border="1">
<tr><td width="150">Target [nodex]</td><td> The Node which is decaying</td></tr>
<tr><td>Half-life [H_nodex]</td><td> The half-life of the Node.</td></tr>
</table>

<p> <b>Usage</b>
<code><font size = "3"><br>&nodex
<blockquote>    &DecayAff  nodex  H_nodex
</blockquote>
&endnodex</code></font>
*/
public class DecayAff extends Affector {
	/** The half-life of the Node in minutes. */
	int		halfLife;
 
	static final String		desc = "First-order decay";
	static final String	[]	nodeDescriptions = {"Target"};
	static final String	[]	paramDescriptions = {"Half-life"};
	static final int	[]	whichSides = { -1 };

	public DecayAff()	{}

	protected void setLabelsAndTypes()	{
		setDescriptions(this.desc, nodeDescriptions, paramDescriptions);
		setSided(true, whichSides);
		setContainsTarget(true);

		this.Type[GUI_CAPABLE] = 1;
		this.Type[CERTIFICATION] = Affector.RETURNS_DERIV;
		this.Type[MATHTYPE] = Affector.HH;
		this.Type[TERMTYPE] = Affector.DEGRADATION;
	}
	
	public void setParameterNumbers(int [] param_nums)
	{
		halfLife = param_nums[0];
	}
	
	public float getValue(Node which_node)	{
		return (Nodes[0].getIntegrationValue(side) * 
				(-Globals.characteristicTime / params[halfLife]));
	}

	public float getNCValue(Node which_node)  {
		return (-Globals.characteristicTime / params[halfLife]);
	}
	
}