<?php
  /*=======================================================================
   // File:        JPGRAPH_UTILS.INC
   // Description: Collection of non-essential "nice to have" utilities
   // Created:     2005-11-20
   // Ver:         $Id: jpgraph_utils.inc.php 1777 2009-08-23 17:34:36Z ljp $
   //
   // Copyright (c) Asial Corporation. All rights reserved.
   //========================================================================
   */
  
  //===================================================
  // CLASS FuncGenerator
  // Description: Utility class to help generate data for function plots.
  // The class supports both parametric and regular functions.
  //===================================================
  class FuncGenerator {
      private $iFunc='',$iXFunc='',$iMin,$iMax,$iStepSize;
  
      function __construct($aFunc,$aXFunc='') {
          $this->iFunc = $aFunc;
          $this->iXFunc = $aXFunc;
      }
  
      function E($aXMin,$aXMax,$aSteps=50) {
          $this->iMin = $aXMin;
          $this->iMax = $aXMax;
          $this->iStepSize = ($aXMax-$aXMin)/$aSteps;
  
          if( $this->iXFunc != '' )
          $t = 'for($i='.$aXMin.'; $i<='.$aXMax.'; $i += '.$this->iStepSize.') {$ya[]='.$this->iFunc.';$xa[]='.$this->iXFunc.';}';
          elseif( $this->iFunc != '' )
          $t = 'for($x='.$aXMin.'; $x<='.$aXMax.'; $x += '.$this->iStepSize.') {$ya[]='.$this->iFunc.';$xa[]=$x;} $x='.$aXMax.';$ya[]='.$this->iFunc.';$xa[]=$x;';
          else
          JpGraphError::RaiseL(24001);//('FuncGenerator : No function specified. ');
  
          @eval($t);
  
          // If there is an error in the function specifcation this is the only
          // way we can discover that.
          if( empty($xa) || empty($ya) )
          JpGraphError::RaiseL(24002);//('FuncGenerator : Syntax error in function specification ');
  
          return array($xa,$ya);
      }
  }
  
  
  //=============================================================================
  // CLASS DateScaleUtils
  // Description: Help to create a manual date scale
  //=============================================================================
  define('DSUTILS_MONTH',1); // Major and minor ticks on a monthly basis
  define('DSUTILS_MONTH1',1); // Major and minor ticks on a monthly basis
  define('DSUTILS_MONTH2',2); // Major ticks on a bi-monthly basis
  define('DSUTILS_MONTH3',3); // Major icks on a tri-monthly basis
  define('DSUTILS_MONTH6',4); // Major on a six-monthly basis
  define('DSUTILS_WEEK1',5); // Major ticks on a weekly basis
  define('DSUTILS_WEEK2',6); // Major ticks on a bi-weekly basis
  define('DSUTILS_WEEK4',7); // Major ticks on a quod-weekly basis
  define('DSUTILS_DAY1',8); // Major ticks on a daily basis
  define('DSUTILS_DAY2',9); // Major ticks on a bi-daily basis
  define('DSUTILS_DAY4',10); // Major ticks on a qoud-daily basis
  define('DSUTILS_YEAR1',11); // Major ticks on a yearly basis
  define('DSUTILS_YEAR2',12); // Major ticks on a bi-yearly basis
  define('DSUTILS_YEAR5',13); // Major ticks on a five-yearly basis
  
  
  class DateScaleUtils {
      public static $iMin=0, $iMax=0;
  
      private static $starthour,$startmonth, $startday, $startyear;
      private static $endmonth, $endyear, $endday;
      private static $tickPositions=array(),$minTickPositions=array();
      private static $iUseWeeks = true;
  
      static function UseWeekFormat($aFlg) {
          self::$iUseWeeks = $aFlg;
      }
  
      static function doYearly($aType,$aMinor=false) {
          $i=0; $j=0;
          $m = self::$startmonth;
          $y = self::$startyear;
  
          if( self::$startday == 1 ) {
              self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
          }
          ++$m;
  
  
          switch( $aType ) {
              case DSUTILS_YEAR1:
                  for($y=self::$startyear; $y <= self::$endyear; ++$y ) {
                      if( $aMinor ) {
                          while( $m <= 12 ) {
                              if( !($y == self::$endyear && $m > self::$endmonth) ) {
                                  self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
                              }
                              ++$m;
                          }
                          $m=1;
                      }
                      self::$tickPositions[$i++] = mktime(0,0,0,1,1,$y);
                  }
                  break;
              case DSUTILS_YEAR2:
                  $y=self::$startyear;
                  while( $y <= self::$endyear ) {
                      self::$tickPositions[$i++] = mktime(0,0,0,1,1,$y);
                      for($k=0; $k < 1; ++$k ) {
                          ++$y;
                          if( $aMinor ) {
                              self::$minTickPositions[$j++] = mktime(0,0,0,1,1,$y);
                          }
                      }
                      ++$y;
                  }
                  break;
              case DSUTILS_YEAR5:
                  $y=self::$startyear;
                  while( $y <= self::$endyear ) {
                      self::$tickPositions[$i++] = mktime(0,0,0,1,1,$y);
                      for($k=0; $k < 4; ++$k ) {
                          ++$y;
                          if( $aMinor ) {
                              self::$minTickPositions[$j++] = mktime(0,0,0,1,1,$y);
                          }
                      }
                      ++$y;
                  }
                  break;
          }
      }
  
      static function doDaily($aType,$aMinor=false) {
          $m = self::$startmonth;
          $y = self::$startyear;
          $d = self::$startday;
          $h = self::$starthour;
          $i=0;$j=0;
  
          if( $h == 0 ) {
              self::$tickPositions[$i++] = mktime(0,0,0,$m,$d,$y);
          }
          $t = mktime(0,0,0,$m,$d,$y);
  
          switch($aType) {
              case DSUTILS_DAY1:
                  while( $t <= self::$iMax ) {
                      $t = strtotime('+1 day',$t);
                      self::$tickPositions[$i++] = $t;
                      if( $aMinor ) {
                          self::$minTickPositions[$j++] = strtotime('+12 hours',$t);
                      }
                  }
                  break;
              case DSUTILS_DAY2:
                  while( $t <= self::$iMax ) {
                      $t = strtotime('+1 day',$t);
                      if( $aMinor ) {
                          self::$minTickPositions[$j++] = $t;
                      }
                      $t = strtotime('+1 day',$t);
                      self::$tickPositions[$i++] = $t;
                  }
                  break;
              case DSUTILS_DAY4:
                  while( $t <= self::$iMax ) {
                      for($k=0; $k < 3; ++$k ) {
                          $t = strtotime('+1 day',$t);
                          if( $aMinor ) {
                              self::$minTickPositions[$j++] = $t;
                          }
                      }
                      $t = strtotime('+1 day',$t);
                      self::$tickPositions[$i++] = $t;
                  }
                  break;
          }
      }
  
      static function doWeekly($aType,$aMinor=false) {
          $hpd = 3600*24;
          $hpw = 3600*24*7;
          // Find out week number of min date
          $thursday = self::$iMin + $hpd * (3 - (date('w', self::$iMin) + 6) % 7);
          $week = 1 + (date('z', $thursday) - (11 - date('w', mktime(0, 0, 0, 1, 1, date('Y', $thursday)))) % 7) / 7;
          $daynumber = date('w',self::$iMin);
          if( $daynumber == 0 ) $daynumber = 7;
          $m = self::$startmonth;
          $y = self::$startyear;
          $d = self::$startday;
          $i=0;$j=0;
          // The assumption is that the weeks start on Monday. If the first day
          // is later in the week then the first week tick has to be on the following
          // week.
          if( $daynumber == 1 ) {
              self::$tickPositions[$i++] = mktime(0,0,0,$m,$d,$y);
              $t = mktime(0,0,0,$m,$d,$y) + $hpw;
          }
          else {
              $t = mktime(0,0,0,$m,$d,$y) + $hpd*(8-$daynumber);
          }
  
          switch($aType) {
              case DSUTILS_WEEK1:
                  $cnt=0;
                  break;
              case DSUTILS_WEEK2:
                  $cnt=1;
                  break;
              case DSUTILS_WEEK4:
                  $cnt=3;
                  break;
          }
          while( $t <= self::$iMax ) {
              self::$tickPositions[$i++] = $t;
              for($k=0; $k < $cnt; ++$k ) {
                  $t += $hpw;
                  if( $aMinor ) {
                      self::$minTickPositions[$j++] = $t;
                  }
              }
              $t += $hpw;
          }
      }
  
      static function doMonthly($aType,$aMinor=false) {
          $monthcount=0;
          $m = self::$startmonth;
          $y = self::$startyear;
          $i=0; $j=0;
  
          // Skip the first month label if it is before the startdate
          if( self::$startday == 1 ) {
              self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
              $monthcount=1;
          }
          if( $aType == 1 ) {
              if( self::$startday < 15 ) {
                  self::$minTickPositions[$j++] = mktime(0,0,0,$m,15,$y);
              }
          }
          ++$m;
  
          // Loop through all the years included in the scale
          for($y=self::$startyear; $y <= self::$endyear; ++$y ) {
              // Loop through all the months. There are three cases to consider:
              // 1. We are in the first year and must start with the startmonth
              // 2. We are in the end year and we must stop at last month of the scale
              // 3. A year in between where we run through all the 12 months
              $stopmonth = $y == self::$endyear ? self::$endmonth : 12;
              while( $m <= $stopmonth ) {
                  switch( $aType ) {
                      case DSUTILS_MONTH1:
                          // Set minor tick at the middle of the month
                          if( $aMinor ) {
                              if( $m <= $stopmonth ) {
                                  if( !($y==self::$endyear && $m==$stopmonth && self::$endday < 15) )
                                  self::$minTickPositions[$j++] = mktime(0,0,0,$m,15,$y);
                              }
                          }
                          // Major at month
                          // Get timestamp of first hour of first day in each month
                          self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
  
                          break;
                      case DSUTILS_MONTH2:
                          if( $aMinor ) {
                              // Set minor tick at start of each month
                              self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
                          }
  
                          // Major at every second month
                          // Get timestamp of first hour of first day in each month
                          if( $monthcount % 2 == 0 ) {
                              self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
                          }
                          break;
                      case DSUTILS_MONTH3:
                          if( $aMinor ) {
                              // Set minor tick at start of each month
                              self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
                          }
                          // Major at every third month
                          // Get timestamp of first hour of first day in each month
                          if( $monthcount % 3 == 0 ) {
                              self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
                          }
                          break;
                      case DSUTILS_MONTH6:
                          if( $aMinor ) {
                              // Set minor tick at start of each month
                              self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
                          }
                          // Major at every third month
                          // Get timestamp of first hour of first day in each month
                          if( $monthcount % 6 == 0 ) {
                              self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
                          }
                          break;
                  }
                  ++$m;
                  ++$monthcount;
              }
              $m=1;
          }
  
          // For the case where all dates are within the same month
          // we want to make sure we have at least two ticks on the scale
          // since the scale want work properly otherwise
          if(self::$startmonth == self::$endmonth && self::$startyear == self::$endyear && $aType==1 ) {
              self::$tickPositions[$i++] = mktime(0 ,0 ,0, self::$startmonth + 1, 1, self::$startyear);
          }
  
          return array(self::$tickPositions,self::$minTickPositions);
      }
  
      static function GetTicks($aData,$aType=1,$aMinor=false,$aEndPoints=false) {
          $n = count($aData);
          return self::GetTicksFromMinMax($aData[0],$aData[$n-1],$aType,$aMinor,$aEndPoints);
      }
  
      static function GetAutoTicks($aMin,$aMax,$aMaxTicks=10,$aMinor=false) {
          $diff = $aMax - $aMin;
          $spd = 3600*24;
          $spw = $spd*7;
          $spm = $spd*30;
          $spy = $spd*352;
  
          if( self::$iUseWeeks )
          $w = 'W';
          else
          $w = 'd M';
  
          // Decision table for suitable scales
          // First value: Main decision point
          // Second value: Array of formatting depending on divisor for wanted max number of ticks. <divisor><formatting><format-string>,..
          $tt = array(
              array($spw, array(1,DSUTILS_DAY1,'d M',2,DSUTILS_DAY2,'d M',-1,DSUTILS_DAY4,'d M')),
              array($spm, array(1,DSUTILS_DAY1,'d M',2,DSUTILS_DAY2,'d M',4,DSUTILS_DAY4,'d M',7,DSUTILS_WEEK1,$w,-1,DSUTILS_WEEK2,$w)),
              array($spy, array(1,DSUTILS_DAY1,'d M',2,DSUTILS_DAY2,'d M',4,DSUTILS_DAY4,'d M',7,DSUTILS_WEEK1,$w,14,DSUTILS_WEEK2,$w,30,DSUTILS_MONTH1,'M',60,DSUTILS_MONTH2,'M',-1,DSUTILS_MONTH3,'M')),
              array(-1, array(30,DSUTILS_MONTH1,'M-Y',60,DSUTILS_MONTH2,'M-Y',90,DSUTILS_MONTH3,'M-Y',180,DSUTILS_MONTH6,'M-Y',352,DSUTILS_YEAR1,'Y',704,DSUTILS_YEAR2,'Y',-1,DSUTILS_YEAR5,'Y')));
  
          $ntt = count($tt);
          $nd = floor($diff/$spd);
          for($i=0; $i < $ntt; ++$i ) {
              if( $diff <= $tt[$i][0] || $i==$ntt-1) {
                  $t = $tt[$i][1];
                  $n = count($t)/3;
                  for( $j=0; $j < $n; ++$j ) {
                      if( $nd/$t[3*$j] <= $aMaxTicks || $j==$n-1) {
                          $type = $t[3*$j+1];
                          $fs = $t[3*$j+2];
                          list($tickPositions,$minTickPositions) = self::GetTicksFromMinMax($aMin,$aMax,$type,$aMinor);
                          return array($fs,$tickPositions,$minTickPositions,$type);
                      }
                  }
              }
          }
      }
  
      static function GetTicksFromMinMax($aMin,$aMax,$aType,$aMinor=false,$aEndPoints=false) {
          self::$starthour = date('G',$aMin);
          self::$startmonth = date('n',$aMin);
          self::$startday = date('j',$aMin);
          self::$startyear = date('Y',$aMin);
          self::$endmonth = date('n',$aMax);
          self::$endyear = date('Y',$aMax);
          self::$endday = date('j',$aMax);
          self::$iMin = $aMin;
          self::$iMax = $aMax;
  
          if( $aType <= DSUTILS_MONTH6 ) {
              self::doMonthly($aType,$aMinor);
          }
          elseif( $aType <= DSUTILS_WEEK4 ) {
              self::doWeekly($aType,$aMinor);
          }
          elseif( $aType <= DSUTILS_DAY4 ) {
              self::doDaily($aType,$aMinor);
          }
          elseif( $aType <= DSUTILS_YEAR5 ) {
              self::doYearly($aType,$aMinor);
          }
          else {
              JpGraphError::RaiseL(24003);
          }
          // put a label at the very left data pos
          if( $aEndPoints ) {
              $tickPositions[$i++] = $aData[0];
          }
  
          // put a label at the very right data pos
          if( $aEndPoints ) {
              $tickPositions[$i] = $aData[$n-1];
          }
  
          return array(self::$tickPositions,self::$minTickPositions);
      }
  }
  
  //=============================================================================
  // Class ReadFileData
  //=============================================================================
  Class ReadFileData {
      //----------------------------------------------------------------------------
      // Desciption:
      // Read numeric data from a file.
      // Each value should be separated by either a new line or by a specified
      // separator character (default is ',').
      // Before returning the data each value is converted to a proper float
      // value. The routine is robust in the sense that non numeric data in the
      // file will be discarded.
      //
      // Returns:
      // The number of data values read on success, FALSE on failure
      //----------------------------------------------------------------------------
      static function FromCSV($aFile,&$aData,$aSepChar=',',$aMaxLineLength=1024) {
          $rh = @fopen($aFile,'r');
          if( $rh === false ) {
                  return false;
          }
          $tmp = array();
          $lineofdata = fgetcsv($rh, 1000, ',');
          while ( $lineofdata !== FALSE) {
              $tmp = array_merge($tmp,$lineofdata);
              $lineofdata = fgetcsv($rh, $aMaxLineLength, $aSepChar);
          }
          fclose($rh);
  
          // Now make sure that all data is numeric. By default
          // all data is read as strings
          $n = count($tmp);
          $aData = array();
          $cnt=0;
          for($i=0; $i < $n; ++$i) {
              if( $tmp[$i] !== "" ) {
                  $aData[$cnt++] = floatval($tmp[$i]);
              }
          }
          return $cnt;
      }
  
      //----------------------------------------------------------------------------
      // Desciption:
      // Read numeric data from a file.
      // Each value should be separated by either a new line or by a specified
      // separator character (default is ',').
      // Before returning the data each value is converted to a proper float
      // value. The routine is robust in the sense that non numeric data in the
      // file will be discarded.
      //
      // Options:
      // 'separator'     => ',',
      // 'enclosure'     => '"',
      // 'readlength'    => 1024,
      // 'ignore_first'  => false,
      // 'first_as_key'  => false
      // 'escape'        => '\',   # PHP >= 5.3 only
      //
      // Returns:
      // The number of lines read on success, FALSE on failure
      //----------------------------------------------------------------------------
      static function FromCSV2($aFile, &$aData, $aOptions = array()) {
          $aDefaults = array(
              'separator'     => ',',
              'enclosure'     => chr(34),
              'escape'        => chr(92),
              'readlength'    => 1024,
              'ignore_first'  => false,
              'first_as_key'  => false
              );
  
          $aOptions = array_merge(
              $aDefaults, is_array($aOptions) ? $aOptions : array());
  
          if( $aOptions['first_as_key'] ) {
              $aOptions['ignore_first'] =  true;
          }
  
          $rh = @fopen($aFile, 'r');
  
          if( $rh === false ) {
              return false;
          }
  
          $aData  = array();
          $aLine  = fgetcsv($rh,
                            $aOptions['readlength'],
                            $aOptions['separator'],
                            $aOptions['enclosure']
                            /*, $aOptions['escape']     # PHP >= 5.3 only */
                            );
  
          // Use numeric array keys for the columns by default
          // If specified use first lines values as assoc keys instead
          $keys = array_keys($aLine);
          if( $aOptions['first_as_key'] ) {
              $keys = array_values($aLine);
          }
  
          $num_lines = 0;
          $num_cols  = count($aLine);
  
          while ($aLine !== false) {
              if( is_array($aLine) && count($aLine) != $num_cols ) {
                  JpGraphError::RaiseL(24004);
                  // 'ReadCSV2: Column count mismatch in %s line %d'
              }
  
              // fgetcsv returns NULL for empty lines
              if( !is_null($aLine) ) {
                  $num_lines++;
  
                  if( !($aOptions['ignore_first'] && $num_lines == 1) && is_numeric($aLine[0]) ) {
                      for( $i = 0; $i < $num_cols; $i++ ) {
                          $aData[ $keys[$i] ][] = floatval($aLine[$i]);
                      }
                  }
              }
  
              $aLine = fgetcsv($rh,
                               $aOptions['readlength'],
                               $aOptions['separator'],
                               $aOptions['enclosure']
                               /*, $aOptions['escape']     # PHP >= 5.3 only*/
                  );
          }
  
          fclose($rh);
  
          if( $aOptions['ignore_first'] ) {
              $num_lines--;
          }
  
          return $num_lines;
      }
  
      // Read data from two columns in a plain text file
      static function From2Col($aFile, $aCol1, $aCol2, $aSepChar=' ') {
          $lines = @file($aFile,FILE_IGNORE_NEW_LINES|FILE_SKIP_EMPTY_LINES);
          if( $lines === false ) {
                  return false;
          }
          $s = '/[\s]+/';
          if( $aSepChar == ',' ) {
                          $s = '/[\s]*,[\s]*/';
          }
          elseif( $aSepChar == ';' ) {
                          $s = '/[\s]*;[\s]*/';
          }
          foreach( $lines as $line => $datarow ) {
                  $split = preg_split($s,$datarow);
                  $aCol1[] = floatval(trim($split[0]));
                  $aCol2[] = floatval(trim($split[1]));
          }
  
          return count($lines);
      }
  
      // Read data from one columns in a plain text file
      static function From1Col($aFile, $aCol1) {
          $lines = @file($aFile,FILE_IGNORE_NEW_LINES|FILE_SKIP_EMPTY_LINES);
          if( $lines === false ) {
                  return false;
          }
          foreach( $lines as $line => $datarow ) {
                  $aCol1[] = floatval(trim($datarow));
          }
  
          return count($lines);
      }
  
      static function FromMatrix($aFile,$aSepChar=' ') {
          $lines = @file($aFile,FILE_IGNORE_NEW_LINES|FILE_SKIP_EMPTY_LINES);
          if( $lines === false ) {
                  return false;
          }
          $mat = array();
          $reg = '/'.$aSepChar.'/';
          foreach( $lines as $line => $datarow ) {
                  $row = preg_split($reg,trim($datarow));
                  foreach ($row as $key => $cell ) {
                          $row[$key] = floatval(trim($cell));
                  }
                  $mat[] = $row;
          }
          return $mat;
      }
  
  
  }
  
  define('__LR_EPSILON', 1.0e-8);
  //=============================================================================
  // Class LinearRegression
  //=============================================================================
  class LinearRegression {
          private $ix=array(),$iy=array();
          private $ib=0, $ia=0;
          private $icalculated=false;
          public $iDet=0, $iCorr=0, $iStdErr=0;
  
          public function __construct($aDataX,$aDataY) {
                  if( count($aDataX) !== count($aDataY) ) {
                          JpGraph::Raise('LinearRegression: X and Y data array must be of equal length.');
                  }
                  $this->ix = $aDataX;
                  $this->iy = $aDataY;
          }
  
          public function Calc() {
  
                  $this->icalculated = true;
  
                  $n = count($this->ix);
                  $sx2 = 0 ;
                  $sy2 = 0 ;
                  $sxy = 0 ;
                  $sx = 0 ;
                  $sy = 0 ;
  
                  for( $i=0; $i < $n; ++$i ) {
                          $sx2 += $this->ix[$i] * $this->ix[$i];
                          $sy2 += $this->iy[$i] * $this->iy[$i];
                          $sxy += $this->ix[$i] * $this->iy[$i];
                          $sx += $this->ix[$i];
                          $sy += $this->iy[$i];
                  }
  
                  if( $n*$sx2 - $sx*$sx > __LR_EPSILON ) {
                          $this->ib = ($n*$sxy - $sx*$sy) / ( $n*$sx2 - $sx*$sx );
                          $this->ia = ( $sy - $this->ib*$sx ) / $n;
  
                          $sx = $this->ib * ( $sxy - $sx*$sy/$n );
                          $sy2 = $sy2 - $sy*$sy/$n;
                          $sy = $sy2 - $sx;
  
                          $this->iDet = $sx / $sy2;
                          $this->iCorr = sqrt($this->iDet);
                          if( $n > 2 ) {
                                  $this->iStdErr = sqrt( $sy / ($n-2) );
                          }
                          else {
                                  $this->iStdErr = NAN ;
                          }
                  }
                  else {
                          $this->ib = 0;
                          $this->ia = 0;
                  }
  
          }
  
          public function GetAB() {
                  if( $this->icalculated == false )
                          $this->Calc();
                  return array($this->ia, $this->ib);
          }
  
          public function GetStat() {
                  if( $this->icalculated == false )
                          $this->Calc();
                  return array($this->iStdErr, $this->iCorr, $this->iDet);
          }
  
          public function GetY($aMinX, $aMaxX, $aStep=1) {
                  if( $this->icalculated == false )
                          $this->Calc();
  
                  $yy = array();
                  $i = 0;
                  for( $x=$aMinX; $x <= $aMaxX; $x += $aStep ) {
                          $xx[$i  ] = $x;
                          $yy[$i++] = $this->ia + $this->ib * $x;
                  }
  
                  return array($xx,$yy);
          }
  
  }
  
  ?>