variables.cpp

/*
 * 
 * This is a simple variable list for scicalc
 * 
 * Friedrich Feichtinger, 13.09.2012
 * 
 */

#include "variables.h"
#include "parseException.h"

#include <cmath>
#include <QDebug>


QList<Variable*>Variables::variables;


void Variables::init()
{
	variables.clear();

	// math
	set("pi", M_PI);

	// mechanic
	set("_g", 9.81);
	set("_G", 6.67384e-11);

	// electromagnetism
	set("_mu0", 4*M_PI*1e-7);
	set("_eps0", 8.85418781762e-12);
	set("_c0", 299792458);
	set("_e", 1.60217653e-19);

	// thermodynamic
	set("_kB", 1.3806488e-23);

	// quantum physic
	set("_h", 6.62606957e-34);

}


void Variables::set(QString name, long double value)
{
	//qDebug() << "setVariable" << name;
	// search the list for this name
	Variable* var=search(name);

	// check if variable allready exists
	if(var==0)
	{
		// no: let's make a new variable
		var=new Variable(name, value);
		variables.append(var);
	}
	else
	{
		// yes: let's change it's value
		var->value=value;
	}
}


long double Variables::get(QString name)
{
	Variable* var=search(name);
	if(var==0)
	{
		throw ParseException("variable '"+name+"' has no value yet");
	}
	else
	{
		return var->value;
	}
}



Variable* Variables::search(QString name)
{
	for(int i=0; i<variables.length(); i++)
	{
		if(variables.at(i)->name==name)
		{
			return variables.at(i);
		}
	}
	return 0;
}