1 files changed, 95 insertions, 0 deletions
diff --git a/src/electronics/simulation/resistance.cpp b/src/electronics/simulation/resistance.cpp
new file mode 100644
index 0000000..9c2d25d
--- /dev/null
+++ b/src/electronics/simulation/resistance.cpp
@@ -0,0 +1,95 @@
+/***************************************************************************
+ *   Copyright (C) 2003-2004 by David Saxton                               *
+ *   david@bluehaze.org                                                    *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ ***************************************************************************/
+
+#include "elementset.h"
+#include "matrix.h"
+#include "resistance.h"
+
+// #include <kdebug.h>
+
+Resistance::Resistance( const double resistance )
+	: Element::Element()
+{
+	m_g = resistance < 1e-9 ? 1e9 : 1./resistance;
+	m_numCNodes = 2;
+// 	kdDebug() << k_funcinfo << endl;
+}
+
+Resistance::~Resistance()
+{
+// 	kdDebug() << k_funcinfo << endl;
+}
+
+void Resistance::setConductance( const double g )
+{
+	if ( g == m_g )
+		return;
+	
+	if (p_eSet)
+		p_eSet->setCacheInvalidated();
+	
+	// Remove old resistance
+	m_g = -m_g;
+	add_initial_dc();
+
+	m_g = g;
+	add_initial_dc();
+}
+
+
+void Resistance::setResistance( const double r )
+{
+	setConductance( r < 1e-9 ? 1e9 : 1./r );
+}
+
+
+void Resistance::add_map()
+{
+	if (!b_status)
+		return;
+	
+	if ( !p_cnode[0]->isGround )
+	{
+		p_A->setUse( p_cnode[0]->n(), p_cnode[0]->n(), Map::et_stable, false );
+	}
+	if ( !p_cnode[1]->isGround ) {
+		p_A->setUse( p_cnode[1]->n(), p_cnode[1]->n(), Map::et_stable, false );
+	}
+	
+	if ( !p_cnode[0]->isGround && !p_cnode[1]->isGround )
+	{
+		p_A->setUse( p_cnode[0]->n(), p_cnode[1]->n(), Map::et_stable, false );
+		p_A->setUse( p_cnode[1]->n(), p_cnode[0]->n(), Map::et_stable, false );
+	}
+}
+
+
+void Resistance::add_initial_dc()
+{
+	if (!b_status) return;
+	
+	A_g( 0, 0 ) += m_g;
+	A_g( 1, 1 ) += m_g;
+	A_g( 0, 1 ) -= m_g;
+	A_g( 1, 0 ) -= m_g;
+}
+
+
+void Resistance::updateCurrents()
+{
+	if (!b_status) return;
+	const double v=p_cnode[0]->v-p_cnode[1]->v; 
+	m_cnodeI[1] = v*m_g;
+	m_cnodeI[0] = -m_cnodeI[1];
+}
+
+
+
+