/*
 * THIS FILE IS AUTOMATICALLY GENERATED BY THE s2j SCRIPT
 * DO NOT EDIT.
 * If you wish to make permanent changes, you should use this file
 * to test your changes, and then modify s2j so that the automatically
 * generated version of Model.java has those changes.
 * When committing changes to CVS, please commit both the s2j
 * script and the new version of Model.java
 */
/*
 * Model.java - stella2java model file.
 * Copyright 1999-2003 David A. Joiner and the Shodor Edcuation
 * Foundation, Inc.
 */
import java.awt.*;
import java.applet.Applet;
import java.util.*;

class Model extends Diffeq {


   double PI = 3.14159;

   Random randomNumber = new Random();

   double tinitial;
   double tfinal;
   double tstep_default;

   int try_model=0;

   int ntime;
   double []xtime;

   int method;

   int n_vars;
   int n_varfs;
   int n_vartot;
   int n_rates;
   int n_convs;
   int n_flows;
   int n_graphs;
   int n_tot;
   String [] var_label;
   String [] varf_label;
   String [] rate_label;
   String [] conv_label;
   String [] flow_label;
   String output_header;
   double [] var_minsb;
   double [] rate_minsb;
   double [] var_maxsb;
   double [] rate_maxsb;
   double [] var_defaultsb;
   double [] rate_defaultsb;
   int [] var_stylesb;
   int [] rate_stylesb;
   double ymin_default;
   double ymax_default;
   double [] rate;
   double [] conv;
   double [] flow;
   double [][] x_graph;
   double [][] y_graph;
   int [] type_graph;
   int [] n_graph;
   static int LINE_GRAPH=0;
   static int BOX_GRAPH=1;
   boolean [] allow_display;
   boolean [] default_display;
   String gr_title;
   String gr_depLabel;

   boolean it_enable;
   boolean ft_enable;
   boolean st_enable;
   boolean imeth_enable;
   boolean ymin_enable;
   boolean ymax_enable;
   boolean adap_enable;
   boolean adap_default;

   double tstep;

   public void init_problem(double st){

      // set default status of control display.
      it_enable=true;
      ft_enable=true;
      st_enable=true;
      imeth_enable=true;
      ymin_enable=true;
      ymax_enable=true;
      adap_enable=true;
      adap_default=true;

      tstep_default=0.25   ;
      ymin_default=600000 ;
      ymax_default=1500000;
      tinitial=2004       ;
      tfinal=2029         ;
      tstep=st;
      time=tinitial;

// CHANGE THE FOLLOWING WHEN USING THIS TEMPLATE //
// --- Set the number of variables and rates --- //
      n_vars=0 ;
      n_varfs=1 ;
      n_vartot=n_vars+n_varfs;
      n_rates=4 ;
      n_convs=0 ;
      n_flows=4 ;
      n_tot=n_vartot+n_rates+n_convs+n_flows;

      allow_display = new boolean[n_tot];
      default_display = new boolean[n_tot];
      allow_display[0]=true;  //Population
      default_display[0]=true;
      allow_display[1]=false;  //
      default_display[1]=false;
      allow_display[2]=false;  //
      default_display[2]=false;
      allow_display[3]=false;  //
      default_display[3]=false;
      allow_display[4]=false;  //
      default_display[4]=false;
      allow_display[5]=false;  //
      default_display[5]=false;
      allow_display[6]=false;  //
      default_display[6]=false;
      allow_display[7]=false;  //
      default_display[7]=false;
      allow_display[8]=false;  //
      default_display[8]=false;

      n_graphs=0;
      n_graph=new int[n_graphs];
      type_graph=new int[n_graphs];

      int max_graph=0;

      for (int i=0;i<n_graphs;i++) {
         if(n_graph[i]>max_graph) max_graph=n_graph[i];
      }




// --------------------------------------------- //
      init(n_vartot);
      rate = new double[n_rates];
      conv = new double[n_convs];
      flow = new double[n_flows];

      ntime=100;
      xtime = new double[ntime*(1+n_tot)];

      var_label=new String[n_vars];
      varf_label=new String[n_varfs];
      rate_label=new String[n_rates];
      conv_label=new String[n_convs];
      flow_label=new String[n_flows];

      var_minsb=new double[n_vars];
      rate_minsb=new double[n_rates];
      var_maxsb=new double[n_vars];
      rate_maxsb=new double[n_rates];
      var_defaultsb=new double[n_vars];
      rate_defaultsb=new double[n_rates];
      var_stylesb=new int[n_vars];
      rate_stylesb=new int[n_rates];

// --- Set default size and value for model ---- //
      double Births;
      double migrants_in;
      double deaths;
      double migrants_out;
      rate[0] = 15.8/1000.0 ;
      rate[1] = 4.7/1000.0 ;
      rate[2] = 65.0/1000.0 ;
      rate[3] = 61.0/1000.0 ;
      x[0+n_vars] = 655000.0 ;
      flow[0] = x[0+n_vars]*rate[0] ;
      flow[1] = x[0+n_vars]*rate[3]  ;
      flow[2] = x[0+n_vars]*rate[1] ;
      flow[3] = x[0+n_vars]*rate[2] ;

      rate_minsb[0]=0;
      rate_minsb[1]=0;
      rate_minsb[2]=0;
      rate_minsb[3]=0;
      rate_maxsb[0]=0.05;
      rate_maxsb[1]=0.05;
      rate_maxsb[2]=0.2;
      rate_maxsb[3]=0.2;
      rate_defaultsb[0]=rate[0];
      rate_defaultsb[1]=rate[1];
      rate_defaultsb[2]=rate[2];
      rate_defaultsb[3]=rate[3];
      rate_stylesb[0]=Slider.STYLE_LINEAR;
      rate_stylesb[1]=Slider.STYLE_LINEAR;
      rate_stylesb[2]=Slider.STYLE_LINEAR;
      rate_stylesb[3]=Slider.STYLE_LINEAR;

    gr_title = new String("AK");

    gr_depLabel = new String("pop");

// --------------------------------------------- //

// ------- Label variables and rates ----------- //
      varf_label[0]="Population";
      rate_label[0]="Birth_rate";
      rate_label[1]="Death_rate";
      rate_label[2]="emigration_rate";
      rate_label[3]="immigration_rate";
      flow_label[0]="Births";
      flow_label[1]="migrants_in";
      flow_label[2]="deaths";
      flow_label[3]="migrants_out";
      output_header=new String();
// --- Set the header line for text output ----- //
      output_header= "\tTime\tvar1\tvar2\tvar3 \n";

      output_header+="---------------------------------------------------";
// --------------------------------------------- //
      method=EULER;
   }

   public void reset_xtime(int newn) {
      if(newn==ntime) return;
      ntime=newn;
      xtime = new double[ntime*(1+n_tot)];
   }


   public void solve(double [] x_var, double [] x_rate,
      double it, double ft,double st, boolean adaptive){

      tinitial=it;
      tfinal=ft;
      time=tinitial;
      tstep=st;

      int newn=(int)((tfinal-tinitial)/st)+1;
      reset_xtime(newn);

      for(int i=0;i<n_vars;i++) {
         x[i]=x_var[i];
      }
      for(int i=0;i<n_rates;i++) {
         rate[i]=x_rate[i];
      }
      // initial values for nvarfs, as well as converters and flows
      // goes here.
      double Births;
      double migrants_in;
      double deaths;
      double migrants_out;
      x[0+n_vars] = 655000.0 ;
      flow[0] = x[0+n_vars]*rate[0] ;
      flow[1] = x[0+n_vars]*rate[3]  ;
      flow[2] = x[0+n_vars]*rate[1] ;
      flow[3] = x[0+n_vars]*rate[2] ;

      double tstep=(tfinal-tinitial)/(double)(ntime-1);
      for(int i=0;i<ntime;i++) {
         xtime[i]=time;
         for (int j=0; j<n_vartot; j++ ) {
            xtime[i+(j+1)*ntime]=x[j];
         }
         for (int j=0; j<n_rates; j++ ) {
            xtime[i+(j+n_vartot+1)*ntime]=rate[j];
         }
         for (int j=0; j<n_convs; j++ ) {
            xtime[i+(j+n_vartot+n_rates+1)*ntime]=conv[j];
         }
         for (int j=0; j<n_flows; j++ ) {
            xtime[i+(j+n_vartot+n_rates+n_convs+1)*ntime]=flow[j];
         }
         if(try_model==1) {
            if(adaptive) {
               updateAdaptive(tstep,0.1,0.01*tstep,method);
            } else {
               update(tstep,method);
            }
         }
      }
   }
   public void deriv(int n,double t,double st,double x[],double xprime[]){
      double Births;
      double migrants_in;
      double deaths;
      double migrants_out;
      flow[0] = x[0+n_vars]*rate[0] ;
      flow[1] = x[0+n_vars]*rate[3]  ;
      flow[2] = x[0+n_vars]*rate[1] ;
      flow[3] = x[0+n_vars]*rate[2] ;
      xprime[0+n_vars]=flow[0]+flow[1]-flow[2]-flow[3];
   }

   public double pulse(double x) {
      return (x/tstep);
   }

   public double pulse(double x, double first_t, double interval_t) {
      if (time>first_t && remainder(time,interval_t)>0.0 &&
	        remainder(time,interval_t)<=tstep)
	     return (x/tstep);
      else
	     return 0.0;

   }

   public double ramp(double slope) {
       return time*slope;
   }

   public double ramp(double slope,double ramp_start) {
       if (time>ramp_start) {
           return (time-ramp_start)*slope;
       } else {
           return 0;
       }
   }

   public double step(double height,double step_time) {
       if(time>=step_time) {
           return height;
       } else {
           return 0;
       }
   }

   public double graph(int index,double dep_var) {
      //access xgraph_i,j, ygraph_i,j, ngraph_i, n_graphs.
      if(dep_var<x_graph[index][0]) {
         //take lower boundary value
         return y_graph[index][0];
      } else if(dep_var>x_graph[index][n_graph[index]-1]) {
         //take upper boundary value
         return y_graph[index][n_graph[index]-1];
      } else {
         //find which element to use, linear intepolation
         for(int i=0;i<n_graph[index]-1;i++) {
            if(dep_var>=x_graph[index][i]&&dep_var<x_graph[index][i+1]) {
               if(type_graph[index]==LINE_GRAPH) {
	                 double slope = (y_graph[index][i+1]-y_graph[index][i])/
	                    (x_graph[index][i+1]-x_graph[index][i]);
	                 return y_graph[index][i]+slope*(dep_var-x_graph[index][i]);
	              } else {
	                 return y_graph[index][i];
	              }
            }
         }
         return y_graph[index][n_graph[index]-1];
      }
   }

   public double remainder(double x, double y) {
      double temp=Math.IEEEremainder(x,y);
      if(temp<0.0) temp=temp+y;
      return temp;
   }

   public double log10(double x) {
      return Math.log(x)/Math.log(10.0);
   }

   public double random(double min, double max) {
      return min+(max-min)*Math.random();
   }

   public double normal(double mean, double standardDeviation){
      return mean + standardDeviation*randomNumber.nextGaussian();
   }

   public double to_int(double x) {
       return (int)x;
   }

   public double poisson(double mu) {
      int retval=1;
      double product=Math.random();
      double test = Math.exp(-mu);
      while (product>test) {
         retval++;
         product*=Math.random();
      }
      return (double)retval;
   }


 }