stats.cpp

/*
    $Id: stats.cpp 466447 2005-10-02 17:54:10Z zander $
 
    KCalc, a scientific calculator for the X window system using the
    TQt widget libraries, available at no cost at http://www.troll.no
 
    Copyright (C) 1996 Bernd Johannes Wuebben
                       wuebben@math.cornell.edu
 
    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.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 
*/
 
 
#include "stats.h"
#include <stdio.h>
#include <stdlib.h>
 
KStats::KStats(){
 
  error_flag = false;
  data.setAutoDelete(true);
 
}
 
KStats::~KStats(){
 
  data.clear();
 
}
 
void KStats::clearAll(){
 
  data.clear();
 
}
 
void KStats::enterData(CALCAMNT _data){
 
  CALCAMNT *newdata;
  newdata = new CALCAMNT;
  *newdata = _data;
  data.append(newdata);
 
#ifdef DEBUG_STATS
  printf("Added %Lg\n",*newdata);
  printf("count %d\n",data.count());
#endif
 
}
 
 
void KStats::clearLast(){
 
 
 data.removeLast();
#ifdef DEBUG_STATS
printf("count %d\n",data.count());
#endif
 
 
}
 
CALCAMNT KStats::sum(){
 
  CALCAMNT result = 0.0;
  CALCAMNT *dp;
  for ( dp=data.first(); dp != 0; dp=data.next() ){
 
    result += *dp;
 
  }
 
#ifdef DEBUG_STATS
  printf("Sum %Lg\n",result);
#endif
 
  return result;
}
 
CALCAMNT KStats::min()
{
  printf("MIIINNNN\n");
 
  if ( data.count() == 0 )
    return 0.0;
 
  printf("1\n");
 
  CALCAMNT result = *(data.first());
  printf("result=%f\n",result);
 
  CALCAMNT *dp = data.next();
  for ( ; dp != 0; dp=data.next() )
    if ( *dp < result )
      result = *dp;
 
  printf("Return\n");
 
  return result;
}
 
CALCAMNT KStats::max()
{
  if ( data.count() == 0 )
    return 0.0;
 
  CALCAMNT result = *(data.first());
  CALCAMNT *dp = data.next();
  for ( ; dp != 0; dp=data.next() )
    if ( *dp > result )
      result = *dp;
 
  return result;
}
 
CALCAMNT KStats::mul(){
 
  CALCAMNT result = 1.0;
  CALCAMNT *dp;
  for ( dp=data.first(); dp != 0; dp=data.next() ){
 
    result *= *dp;
 
  }
 
  return result;
}
 
CALCAMNT KStats::median(){
 
  int index;
  CALCAMNT result;
  CALCAMNT *dp;
  int bound = 0;
 
  MyList list;
 
  for ( dp=data.first(); dp != 0; dp=data.next() ){
    list.inSort(dp);
  }
 
#ifdef DEBUG_STATS
  for(int l = 0; l < (int)list.count();l++){
 
    printf("Sorted %Lg\n",*list.at(l));
 
  }
#endif
 
  bound = list.count();
 
  if (bound == 0){
    error_flag = true;
    return 0.0;
  }
 
  if ( bound == 1)
    return *list.at(0);
 
  if( bound % 2){  // odd
 
    index = (bound - 1 ) / 2 + 1;
    result =  *list.at(index - 1 );
  }
  else { // even
 
    index = bound / 2;
    result = ((*list.at(index - 1))  + (*list.at(index)))/2;
 }
 
  return result;
 
}
 
 
 
CALCAMNT KStats::std_kernel(){
 
  CALCAMNT result = 0.0;
  CALCAMNT _mean;
 
  _mean = mean();
 
  CALCAMNT *dp;
  for ( dp=data.first(); dp != 0; dp=data.next() ){
 
    result += (*dp - _mean) * (*dp - _mean);
 
  }
 
#ifdef DEBUG_STATS
  printf("std_kernel %Lg\n",result);
#endif
 
  return result;
 
}
 
 
CALCAMNT KStats::sum_of_squares(){
 
  CALCAMNT result = 0.0;
  CALCAMNT *dp;
  for ( dp=data.first(); dp != 0; dp=data.next() ){
 
    result += (*dp) * (*dp);
 
  }
 
#ifdef DEBUG_STATS
  printf("Sum of Squares %Lg\n",result);
#endif
 
  return result;
 
}
 
CALCAMNT KStats::mean(){
 
  CALCAMNT result = 0.0;
 
  if(data.count() == 0){
    error_flag = true;
    return 0.0;
  }
 
  result = sum()/data.count();
 
#ifdef DEBUG_STATS
  printf("mean: %Lg\n",result);
#endif
 
  return result;
 
}
 
CALCAMNT KStats::std(){
 
  CALCAMNT result = 0.0;
 
  if(data.count() == 0){
    error_flag = true;
 
#ifdef DEBUG_STATS
    printf("set stats error\n");
#endif
 
    return 0.0;
  }
 
  result = SQRT(std_kernel());
 
#ifdef DEBUG_STATS
  printf ("data.count %d\n",data.count());
#endif
 
  result = result/data.count();
 
#ifdef DEBUG_STATS
  printf("std: %Lg\n",result);
#endif
 
  return result;
 
}
 
CALCAMNT KStats::sample_std(){
 
  CALCAMNT result = 0.0;
 
  if(data.count() < 2 ){
    error_flag = true;
    return 0.0;
  }
 
  result = SQRT(std_kernel());
  result = result/(data.count() - 1);
#ifdef DEBUG_STATS
  printf("sample std: %Lg\n",result);
#endif
  return result;
 
}
 
int  KStats::count(){
 
  return data.count();
 
}
 
bool KStats::error(){
 
  bool value;
  value = error_flag;
  error_flag = false;
 
  return value;
 
}
 
int MyList::compareItems(Item item_1, Item item_2){
 
  CALCAMNT *item1;
  CALCAMNT *item2;
 
  item1 = (CALCAMNT*) item_1;
  item2 = (CALCAMNT*) item_2;
 
  if(*item1 > *item2)
    return 1;
 
  if(*item2 > *item1)
    return -1;
 
  return 0;
 
}