source: trunk/xgraph/jpgraph/jpgraph_utils.inc.php@ 43

Last change on this file since 43 was 42, checked in by marrucho, 11 years ago
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1<?php
2/*=======================================================================
3 // File: JPGRAPH_UTILS.INC
4 // Description: Collection of non-essential "nice to have" utilities
5 // Created: 2005-11-20
6 // Ver: $Id: jpgraph_utils.inc.php 1777 2009-08-23 17:34:36Z ljp $
7 //
8 // Copyright (c) Asial Corporation. All rights reserved.
9 //========================================================================
10 */
11
12//===================================================
13// CLASS FuncGenerator
14// Description: Utility class to help generate data for function plots.
15// The class supports both parametric and regular functions.
16//===================================================
17class FuncGenerator {
18 private $iFunc='',$iXFunc='',$iMin,$iMax,$iStepSize;
19
20 function __construct($aFunc,$aXFunc='') {
21 $this->iFunc = $aFunc;
22 $this->iXFunc = $aXFunc;
23 }
24
25 function E($aXMin,$aXMax,$aSteps=50) {
26 $this->iMin = $aXMin;
27 $this->iMax = $aXMax;
28 $this->iStepSize = ($aXMax-$aXMin)/$aSteps;
29
30 if( $this->iXFunc != '' )
31 $t = 'for($i='.$aXMin.'; $i<='.$aXMax.'; $i += '.$this->iStepSize.') {$ya[]='.$this->iFunc.';$xa[]='.$this->iXFunc.';}';
32 elseif( $this->iFunc != '' )
33 $t = 'for($x='.$aXMin.'; $x<='.$aXMax.'; $x += '.$this->iStepSize.') {$ya[]='.$this->iFunc.';$xa[]=$x;} $x='.$aXMax.';$ya[]='.$this->iFunc.';$xa[]=$x;';
34 else
35 JpGraphError::RaiseL(24001);//('FuncGenerator : No function specified. ');
36
37 @eval($t);
38
39 // If there is an error in the function specifcation this is the only
40 // way we can discover that.
41 if( empty($xa) || empty($ya) )
42 JpGraphError::RaiseL(24002);//('FuncGenerator : Syntax error in function specification ');
43
44 return array($xa,$ya);
45 }
46}
47
48
49//=============================================================================
50// CLASS DateScaleUtils
51// Description: Help to create a manual date scale
52//=============================================================================
53define('DSUTILS_MONTH',1); // Major and minor ticks on a monthly basis
54define('DSUTILS_MONTH1',1); // Major and minor ticks on a monthly basis
55define('DSUTILS_MONTH2',2); // Major ticks on a bi-monthly basis
56define('DSUTILS_MONTH3',3); // Major icks on a tri-monthly basis
57define('DSUTILS_MONTH6',4); // Major on a six-monthly basis
58define('DSUTILS_WEEK1',5); // Major ticks on a weekly basis
59define('DSUTILS_WEEK2',6); // Major ticks on a bi-weekly basis
60define('DSUTILS_WEEK4',7); // Major ticks on a quod-weekly basis
61define('DSUTILS_DAY1',8); // Major ticks on a daily basis
62define('DSUTILS_DAY2',9); // Major ticks on a bi-daily basis
63define('DSUTILS_DAY4',10); // Major ticks on a qoud-daily basis
64define('DSUTILS_YEAR1',11); // Major ticks on a yearly basis
65define('DSUTILS_YEAR2',12); // Major ticks on a bi-yearly basis
66define('DSUTILS_YEAR5',13); // Major ticks on a five-yearly basis
67
68
69class DateScaleUtils {
70 public static $iMin=0, $iMax=0;
71
72 private static $starthour,$startmonth, $startday, $startyear;
73 private static $endmonth, $endyear, $endday;
74 private static $tickPositions=array(),$minTickPositions=array();
75 private static $iUseWeeks = true;
76
77 static function UseWeekFormat($aFlg) {
78 self::$iUseWeeks = $aFlg;
79 }
80
81 static function doYearly($aType,$aMinor=false) {
82 $i=0; $j=0;
83 $m = self::$startmonth;
84 $y = self::$startyear;
85
86 if( self::$startday == 1 ) {
87 self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
88 }
89 ++$m;
90
91
92 switch( $aType ) {
93 case DSUTILS_YEAR1:
94 for($y=self::$startyear; $y <= self::$endyear; ++$y ) {
95 if( $aMinor ) {
96 while( $m <= 12 ) {
97 if( !($y == self::$endyear && $m > self::$endmonth) ) {
98 self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
99 }
100 ++$m;
101 }
102 $m=1;
103 }
104 self::$tickPositions[$i++] = mktime(0,0,0,1,1,$y);
105 }
106 break;
107 case DSUTILS_YEAR2:
108 $y=self::$startyear;
109 while( $y <= self::$endyear ) {
110 self::$tickPositions[$i++] = mktime(0,0,0,1,1,$y);
111 for($k=0; $k < 1; ++$k ) {
112 ++$y;
113 if( $aMinor ) {
114 self::$minTickPositions[$j++] = mktime(0,0,0,1,1,$y);
115 }
116 }
117 ++$y;
118 }
119 break;
120 case DSUTILS_YEAR5:
121 $y=self::$startyear;
122 while( $y <= self::$endyear ) {
123 self::$tickPositions[$i++] = mktime(0,0,0,1,1,$y);
124 for($k=0; $k < 4; ++$k ) {
125 ++$y;
126 if( $aMinor ) {
127 self::$minTickPositions[$j++] = mktime(0,0,0,1,1,$y);
128 }
129 }
130 ++$y;
131 }
132 break;
133 }
134 }
135
136 static function doDaily($aType,$aMinor=false) {
137 $m = self::$startmonth;
138 $y = self::$startyear;
139 $d = self::$startday;
140 $h = self::$starthour;
141 $i=0;$j=0;
142
143 if( $h == 0 ) {
144 self::$tickPositions[$i++] = mktime(0,0,0,$m,$d,$y);
145 }
146 $t = mktime(0,0,0,$m,$d,$y);
147
148 switch($aType) {
149 case DSUTILS_DAY1:
150 while( $t <= self::$iMax ) {
151 $t = strtotime('+1 day',$t);
152 self::$tickPositions[$i++] = $t;
153 if( $aMinor ) {
154 self::$minTickPositions[$j++] = strtotime('+12 hours',$t);
155 }
156 }
157 break;
158 case DSUTILS_DAY2:
159 while( $t <= self::$iMax ) {
160 $t = strtotime('+1 day',$t);
161 if( $aMinor ) {
162 self::$minTickPositions[$j++] = $t;
163 }
164 $t = strtotime('+1 day',$t);
165 self::$tickPositions[$i++] = $t;
166 }
167 break;
168 case DSUTILS_DAY4:
169 while( $t <= self::$iMax ) {
170 for($k=0; $k < 3; ++$k ) {
171 $t = strtotime('+1 day',$t);
172 if( $aMinor ) {
173 self::$minTickPositions[$j++] = $t;
174 }
175 }
176 $t = strtotime('+1 day',$t);
177 self::$tickPositions[$i++] = $t;
178 }
179 break;
180 }
181 }
182
183 static function doWeekly($aType,$aMinor=false) {
184 $hpd = 3600*24;
185 $hpw = 3600*24*7;
186 // Find out week number of min date
187 $thursday = self::$iMin + $hpd * (3 - (date('w', self::$iMin) + 6) % 7);
188 $week = 1 + (date('z', $thursday) - (11 - date('w', mktime(0, 0, 0, 1, 1, date('Y', $thursday)))) % 7) / 7;
189 $daynumber = date('w',self::$iMin);
190 if( $daynumber == 0 ) $daynumber = 7;
191 $m = self::$startmonth;
192 $y = self::$startyear;
193 $d = self::$startday;
194 $i=0;$j=0;
195 // The assumption is that the weeks start on Monday. If the first day
196 // is later in the week then the first week tick has to be on the following
197 // week.
198 if( $daynumber == 1 ) {
199 self::$tickPositions[$i++] = mktime(0,0,0,$m,$d,$y);
200 $t = mktime(0,0,0,$m,$d,$y) + $hpw;
201 }
202 else {
203 $t = mktime(0,0,0,$m,$d,$y) + $hpd*(8-$daynumber);
204 }
205
206 switch($aType) {
207 case DSUTILS_WEEK1:
208 $cnt=0;
209 break;
210 case DSUTILS_WEEK2:
211 $cnt=1;
212 break;
213 case DSUTILS_WEEK4:
214 $cnt=3;
215 break;
216 }
217 while( $t <= self::$iMax ) {
218 self::$tickPositions[$i++] = $t;
219 for($k=0; $k < $cnt; ++$k ) {
220 $t += $hpw;
221 if( $aMinor ) {
222 self::$minTickPositions[$j++] = $t;
223 }
224 }
225 $t += $hpw;
226 }
227 }
228
229 static function doMonthly($aType,$aMinor=false) {
230 $monthcount=0;
231 $m = self::$startmonth;
232 $y = self::$startyear;
233 $i=0; $j=0;
234
235 // Skip the first month label if it is before the startdate
236 if( self::$startday == 1 ) {
237 self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
238 $monthcount=1;
239 }
240 if( $aType == 1 ) {
241 if( self::$startday < 15 ) {
242 self::$minTickPositions[$j++] = mktime(0,0,0,$m,15,$y);
243 }
244 }
245 ++$m;
246
247 // Loop through all the years included in the scale
248 for($y=self::$startyear; $y <= self::$endyear; ++$y ) {
249 // Loop through all the months. There are three cases to consider:
250 // 1. We are in the first year and must start with the startmonth
251 // 2. We are in the end year and we must stop at last month of the scale
252 // 3. A year in between where we run through all the 12 months
253 $stopmonth = $y == self::$endyear ? self::$endmonth : 12;
254 while( $m <= $stopmonth ) {
255 switch( $aType ) {
256 case DSUTILS_MONTH1:
257 // Set minor tick at the middle of the month
258 if( $aMinor ) {
259 if( $m <= $stopmonth ) {
260 if( !($y==self::$endyear && $m==$stopmonth && self::$endday < 15) )
261 self::$minTickPositions[$j++] = mktime(0,0,0,$m,15,$y);
262 }
263 }
264 // Major at month
265 // Get timestamp of first hour of first day in each month
266 self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
267
268 break;
269 case DSUTILS_MONTH2:
270 if( $aMinor ) {
271 // Set minor tick at start of each month
272 self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
273 }
274
275 // Major at every second month
276 // Get timestamp of first hour of first day in each month
277 if( $monthcount % 2 == 0 ) {
278 self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
279 }
280 break;
281 case DSUTILS_MONTH3:
282 if( $aMinor ) {
283 // Set minor tick at start of each month
284 self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
285 }
286 // Major at every third month
287 // Get timestamp of first hour of first day in each month
288 if( $monthcount % 3 == 0 ) {
289 self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
290 }
291 break;
292 case DSUTILS_MONTH6:
293 if( $aMinor ) {
294 // Set minor tick at start of each month
295 self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
296 }
297 // Major at every third month
298 // Get timestamp of first hour of first day in each month
299 if( $monthcount % 6 == 0 ) {
300 self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
301 }
302 break;
303 }
304 ++$m;
305 ++$monthcount;
306 }
307 $m=1;
308 }
309
310 // For the case where all dates are within the same month
311 // we want to make sure we have at least two ticks on the scale
312 // since the scale want work properly otherwise
313 if(self::$startmonth == self::$endmonth && self::$startyear == self::$endyear && $aType==1 ) {
314 self::$tickPositions[$i++] = mktime(0 ,0 ,0, self::$startmonth + 1, 1, self::$startyear);
315 }
316
317 return array(self::$tickPositions,self::$minTickPositions);
318 }
319
320 static function GetTicks($aData,$aType=1,$aMinor=false,$aEndPoints=false) {
321 $n = count($aData);
322 return self::GetTicksFromMinMax($aData[0],$aData[$n-1],$aType,$aMinor,$aEndPoints);
323 }
324
325 static function GetAutoTicks($aMin,$aMax,$aMaxTicks=10,$aMinor=false) {
326 $diff = $aMax - $aMin;
327 $spd = 3600*24;
328 $spw = $spd*7;
329 $spm = $spd*30;
330 $spy = $spd*352;
331
332 if( self::$iUseWeeks )
333 $w = 'W';
334 else
335 $w = 'd M';
336
337 // Decision table for suitable scales
338 // First value: Main decision point
339 // Second value: Array of formatting depending on divisor for wanted max number of ticks. <divisor><formatting><format-string>,..
340 $tt = array(
341 array($spw, array(1,DSUTILS_DAY1,'d M',2,DSUTILS_DAY2,'d M',-1,DSUTILS_DAY4,'d M')),
342 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,$w)),
343 array($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')),
344 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')));
345
346 $ntt = count($tt);
347 $nd = floor($diff/$spd);
348 for($i=0; $i < $ntt; ++$i ) {
349 if( $diff <= $tt[$i][0] || $i==$ntt-1) {
350 $t = $tt[$i][1];
351 $n = count($t)/3;
352 for( $j=0; $j < $n; ++$j ) {
353 if( $nd/$t[3*$j] <= $aMaxTicks || $j==$n-1) {
354 $type = $t[3*$j+1];
355 $fs = $t[3*$j+2];
356 list($tickPositions,$minTickPositions) = self::GetTicksFromMinMax($aMin,$aMax,$type,$aMinor);
357 return array($fs,$tickPositions,$minTickPositions,$type);
358 }
359 }
360 }
361 }
362 }
363
364 static function GetTicksFromMinMax($aMin,$aMax,$aType,$aMinor=false,$aEndPoints=false) {
365 self::$starthour = date('G',$aMin);
366 self::$startmonth = date('n',$aMin);
367 self::$startday = date('j',$aMin);
368 self::$startyear = date('Y',$aMin);
369 self::$endmonth = date('n',$aMax);
370 self::$endyear = date('Y',$aMax);
371 self::$endday = date('j',$aMax);
372 self::$iMin = $aMin;
373 self::$iMax = $aMax;
374
375 if( $aType <= DSUTILS_MONTH6 ) {
376 self::doMonthly($aType,$aMinor);
377 }
378 elseif( $aType <= DSUTILS_WEEK4 ) {
379 self::doWeekly($aType,$aMinor);
380 }
381 elseif( $aType <= DSUTILS_DAY4 ) {
382 self::doDaily($aType,$aMinor);
383 }
384 elseif( $aType <= DSUTILS_YEAR5 ) {
385 self::doYearly($aType,$aMinor);
386 }
387 else {
388 JpGraphError::RaiseL(24003);
389 }
390 // put a label at the very left data pos
391 if( $aEndPoints ) {
392 $tickPositions[$i++] = $aData[0];
393 }
394
395 // put a label at the very right data pos
396 if( $aEndPoints ) {
397 $tickPositions[$i] = $aData[$n-1];
398 }
399
400 return array(self::$tickPositions,self::$minTickPositions);
401 }
402}
403
404//=============================================================================
405// Class ReadFileData
406//=============================================================================
407Class ReadFileData {
408 //----------------------------------------------------------------------------
409 // Desciption:
410 // Read numeric data from a file.
411 // Each value should be separated by either a new line or by a specified
412 // separator character (default is ',').
413 // Before returning the data each value is converted to a proper float
414 // value. The routine is robust in the sense that non numeric data in the
415 // file will be discarded.
416 //
417 // Returns:
418 // The number of data values read on success, FALSE on failure
419 //----------------------------------------------------------------------------
420 static function FromCSV($aFile,&$aData,$aSepChar=',',$aMaxLineLength=1024) {
421 $rh = @fopen($aFile,'r');
422 if( $rh === false ) {
423 return false;
424 }
425 $tmp = array();
426 $lineofdata = fgetcsv($rh, 1000, ',');
427 while ( $lineofdata !== FALSE) {
428 $tmp = array_merge($tmp,$lineofdata);
429 $lineofdata = fgetcsv($rh, $aMaxLineLength, $aSepChar);
430 }
431 fclose($rh);
432
433 // Now make sure that all data is numeric. By default
434 // all data is read as strings
435 $n = count($tmp);
436 $aData = array();
437 $cnt=0;
438 for($i=0; $i < $n; ++$i) {
439 if( $tmp[$i] !== "" ) {
440 $aData[$cnt++] = floatval($tmp[$i]);
441 }
442 }
443 return $cnt;
444 }
445
446 //----------------------------------------------------------------------------
447 // Desciption:
448 // Read numeric data from a file.
449 // Each value should be separated by either a new line or by a specified
450 // separator character (default is ',').
451 // Before returning the data each value is converted to a proper float
452 // value. The routine is robust in the sense that non numeric data in the
453 // file will be discarded.
454 //
455 // Options:
456 // 'separator' => ',',
457 // 'enclosure' => '"',
458 // 'readlength' => 1024,
459 // 'ignore_first' => false,
460 // 'first_as_key' => false
461 // 'escape' => '\', # PHP >= 5.3 only
462 //
463 // Returns:
464 // The number of lines read on success, FALSE on failure
465 //----------------------------------------------------------------------------
466 static function FromCSV2($aFile, &$aData, $aOptions = array()) {
467 $aDefaults = array(
468 'separator' => ',',
469 'enclosure' => chr(34),
470 'escape' => chr(92),
471 'readlength' => 1024,
472 'ignore_first' => false,
473 'first_as_key' => false
474 );
475
476 $aOptions = array_merge(
477 $aDefaults, is_array($aOptions) ? $aOptions : array());
478
479 if( $aOptions['first_as_key'] ) {
480 $aOptions['ignore_first'] = true;
481 }
482
483 $rh = @fopen($aFile, 'r');
484
485 if( $rh === false ) {
486 return false;
487 }
488
489 $aData = array();
490 $aLine = fgetcsv($rh,
491 $aOptions['readlength'],
492 $aOptions['separator'],
493 $aOptions['enclosure']
494 /*, $aOptions['escape'] # PHP >= 5.3 only */
495 );
496
497 // Use numeric array keys for the columns by default
498 // If specified use first lines values as assoc keys instead
499 $keys = array_keys($aLine);
500 if( $aOptions['first_as_key'] ) {
501 $keys = array_values($aLine);
502 }
503
504 $num_lines = 0;
505 $num_cols = count($aLine);
506
507 while ($aLine !== false) {
508 if( is_array($aLine) && count($aLine) != $num_cols ) {
509 JpGraphError::RaiseL(24004);
510 // 'ReadCSV2: Column count mismatch in %s line %d'
511 }
512
513 // fgetcsv returns NULL for empty lines
514 if( !is_null($aLine) ) {
515 $num_lines++;
516
517 if( !($aOptions['ignore_first'] && $num_lines == 1) && is_numeric($aLine[0]) ) {
518 for( $i = 0; $i < $num_cols; $i++ ) {
519 $aData[ $keys[$i] ][] = floatval($aLine[$i]);
520 }
521 }
522 }
523
524 $aLine = fgetcsv($rh,
525 $aOptions['readlength'],
526 $aOptions['separator'],
527 $aOptions['enclosure']
528 /*, $aOptions['escape'] # PHP >= 5.3 only*/
529 );
530 }
531
532 fclose($rh);
533
534 if( $aOptions['ignore_first'] ) {
535 $num_lines--;
536 }
537
538 return $num_lines;
539 }
540
541 // Read data from two columns in a plain text file
542 static function From2Col($aFile, $aCol1, $aCol2, $aSepChar=' ') {
543 $lines = @file($aFile,FILE_IGNORE_NEW_LINES|FILE_SKIP_EMPTY_LINES);
544 if( $lines === false ) {
545 return false;
546 }
547 $s = '/[\s]+/';
548 if( $aSepChar == ',' ) {
549 $s = '/[\s]*,[\s]*/';
550 }
551 elseif( $aSepChar == ';' ) {
552 $s = '/[\s]*;[\s]*/';
553 }
554 foreach( $lines as $line => $datarow ) {
555 $split = preg_split($s,$datarow);
556 $aCol1[] = floatval(trim($split[0]));
557 $aCol2[] = floatval(trim($split[1]));
558 }
559
560 return count($lines);
561 }
562
563 // Read data from one columns in a plain text file
564 static function From1Col($aFile, $aCol1) {
565 $lines = @file($aFile,FILE_IGNORE_NEW_LINES|FILE_SKIP_EMPTY_LINES);
566 if( $lines === false ) {
567 return false;
568 }
569 foreach( $lines as $line => $datarow ) {
570 $aCol1[] = floatval(trim($datarow));
571 }
572
573 return count($lines);
574 }
575
576 static function FromMatrix($aFile,$aSepChar=' ') {
577 $lines = @file($aFile,FILE_IGNORE_NEW_LINES|FILE_SKIP_EMPTY_LINES);
578 if( $lines === false ) {
579 return false;
580 }
581 $mat = array();
582 $reg = '/'.$aSepChar.'/';
583 foreach( $lines as $line => $datarow ) {
584 $row = preg_split($reg,trim($datarow));
585 foreach ($row as $key => $cell ) {
586 $row[$key] = floatval(trim($cell));
587 }
588 $mat[] = $row;
589 }
590 return $mat;
591 }
592
593
594}
595
596define('__LR_EPSILON', 1.0e-8);
597//=============================================================================
598// Class LinearRegression
599//=============================================================================
600class LinearRegression {
601 private $ix=array(),$iy=array();
602 private $ib=0, $ia=0;
603 private $icalculated=false;
604 public $iDet=0, $iCorr=0, $iStdErr=0;
605
606 public function __construct($aDataX,$aDataY) {
607 if( count($aDataX) !== count($aDataY) ) {
608 JpGraph::Raise('LinearRegression: X and Y data array must be of equal length.');
609 }
610 $this->ix = $aDataX;
611 $this->iy = $aDataY;
612 }
613
614 public function Calc() {
615
616 $this->icalculated = true;
617
618 $n = count($this->ix);
619 $sx2 = 0 ;
620 $sy2 = 0 ;
621 $sxy = 0 ;
622 $sx = 0 ;
623 $sy = 0 ;
624
625 for( $i=0; $i < $n; ++$i ) {
626 $sx2 += $this->ix[$i] * $this->ix[$i];
627 $sy2 += $this->iy[$i] * $this->iy[$i];
628 $sxy += $this->ix[$i] * $this->iy[$i];
629 $sx += $this->ix[$i];
630 $sy += $this->iy[$i];
631 }
632
633 if( $n*$sx2 - $sx*$sx > __LR_EPSILON ) {
634 $this->ib = ($n*$sxy - $sx*$sy) / ( $n*$sx2 - $sx*$sx );
635 $this->ia = ( $sy - $this->ib*$sx ) / $n;
636
637 $sx = $this->ib * ( $sxy - $sx*$sy/$n );
638 $sy2 = $sy2 - $sy*$sy/$n;
639 $sy = $sy2 - $sx;
640
641 $this->iDet = $sx / $sy2;
642 $this->iCorr = sqrt($this->iDet);
643 if( $n > 2 ) {
644 $this->iStdErr = sqrt( $sy / ($n-2) );
645 }
646 else {
647 $this->iStdErr = NAN ;
648 }
649 }
650 else {
651 $this->ib = 0;
652 $this->ia = 0;
653 }
654
655 }
656
657 public function GetAB() {
658 if( $this->icalculated == false )
659 $this->Calc();
660 return array($this->ia, $this->ib);
661 }
662
663 public function GetStat() {
664 if( $this->icalculated == false )
665 $this->Calc();
666 return array($this->iStdErr, $this->iCorr, $this->iDet);
667 }
668
669 public function GetY($aMinX, $aMaxX, $aStep=1) {
670 if( $this->icalculated == false )
671 $this->Calc();
672
673 $yy = array();
674 $i = 0;
675 for( $x=$aMinX; $x <= $aMaxX; $x += $aStep ) {
676 $xx[$i ] = $x;
677 $yy[$i++] = $this->ia + $this->ib * $x;
678 }
679
680 return array($xx,$yy);
681 }
682
683}
684
685?>
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