ref: 2344e3a2e1600a2a31e63d2a82a9bbd0b91912b0
dir: /examples/includes/ASCIIMathPHP-2.0/ASCIIMathPHP-2.0.class.php/
<?php
/****
* ASCIIMathPHP and associated classes:
* -- XMLNode
* -- MathMLNode extends XMLNode
*
* These classes are a PHP port of ASCIIMath
* Version 1.3 Feb 19 2004, (c) Peter Jipsen http://www.chapman.edu/~jipsen
*
* ASCIIMathPHP Version 1.11, 26 April 2006, (c) Kee-Lin Steven Chan (kc56@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 (at http://www.gnu.org/copyleft/gpl.html)
* for more details.
*
* ChangeLog
*
* Ver 2.0
* -- PHP5 only version of ASCIIMathPHP
*
* Ver 1.12.1
* -- Included the missing setCurrExpr() method
*
* Ver 1.12
* -- Added changes that David Lippman <DLippman@pierce.ctc.edu> made to bring ASCIIMathPHP up to
* ASCIIMath 1.4.7 functionality.
* -- Added parseIntExpr, for intermediate expression parsing rule, allowing x^2/x^3 to render as (x^2)/(x^3)
* -- Added quotes as another way of designating text; "hello" is equivalent to text(hello)
* -- Added FUNC designator to allow sin, cos, etc to act as functions, so sin(x)/x renders as {sin(x)}/x
*
* Ver 1.11
* -- Fixed bug that stopped script execution for incomplete expressions
* -- Changed the algorithm for parsing expressions so that it matches the longest string possible (greedy)
*
* Ver 1.10
* -- Added definition support
* -- Added stackrel support
* -- Added a bunch of different symbols etc. >>, << and definitions like dx, dy, dz etc.
*
* Ver 1.02
* -- Fixed bug with mbox and text
* -- Fixed spacing bug with mbox and text
*
* Ver 1.01
* -- Fixed Bug that did not parse symbols greater than a single character
* correctly when appearing at end of expression.
*
***/
class XMLNode
{
// Private variables
var $_id;
var $_name;
var $_content;
var $_mt_elem_flg;
var $_attr_arr;
var $_child_arr;
var $_nmspc;
var $_nmspc_alias;
var $_parent_id;
var $_parent_node;
function XMLNode($id = NULL)
{
$this->_id = isset($id) ? $id : md5(uniqid(rand(),1));
$this->_name = '';
$this->_content = '';
$this->_mt_elem_flg = FALSE;
$this->_attr_arr = array();
$this->_child_arr = array();
$this->_nmspc = '';
$this->_nmspc_alias = '';
$this->_parent_id = FALSE;
$this->_parent_node = NULL;
}
function addChild(&$node)
{
$this->_child_arr[$node->getId()] = $node;
$node->setParentId($this->_id);
$node->setParentNode($this);
}
function addChildArr(&$node_arr)
{
$key_arr = array_keys($node_arr);
$num_key = count($key_arr);
for ($i = 0; $i < $num_key; $i++) {
$node = $node_arr[$key_arr[$i]];
$this->addChild($node);
}
}
function insertChildBefore($idx,&$node)
{
$key_arr = array_keys($this->_child_arr);
$num_key = count($key_arr);
$tmp_arr = arry();
for ($i = 0;$i < $num_key;$i++) {
if ($i == $idx) {
$tmp_arr[$node->getId()] = $node;
}
$tmp_arr[$key_arr[$i]] = $this->_child_arr[$key_arr[$i]];
}
$this->_child_arr = $tmp_arr;
}
function insertChildAfter($idx,&$node)
{
$key_arr = array_keys($this->_child_arr);
$num_key = count($key_arr);
$tmp_arr = arry();
for ($i = 0;$i < $num_key;$i++) {
$tmp_arr[$key_arr[$i]] = $this->_child_arr[$key_arr[$i]];
if ($i == $idx) {
$tmp_arr[$node->getId()] = $node;
}
}
$this->_child_arr = $tmp_arr;
}
function setId($id)
{
$this->_id = $id;
}
function setName($name)
{
$this->_name = $name;
}
function setNamepace($nmspc)
{
$this->_nmspc = $nmspc;
}
function setNamespaceAlias($nmspc_alias)
{
$this->_nmspc_alias = $nmspc_alias;
}
function setContent($content)
{
$this->_content = $content;
}
function setEmptyElem($mt_elem_flg)
{
$this->_mt_elem_flg = $mt_elem_flg;
}
function setAttr($attr_nm,$attr_val)
{
$this->_attr_arr[$attr_nm] = $attr_val;
}
function setAttrArr($attr_arr)
{
$this->_attr_arr = $attr_arr;
}
function setParentId($id)
{
$this->_parent_id = $id;
}
function setParentNode(&$node)
{
$this->_parent_node = $node;
}
function getId()
{
return($this->_id);
}
function getName()
{
return($this->_name);
}
function getNamespace()
{
return($this->_nmspc);
}
function getNamespaceAlias()
{
return($this->_nmspc_alias);
}
function getContent()
{
return($this->_content);
}
function getAttr($attr_nm)
{
if (isset($this->_attr_arr[$attr_nm])) {
return($this->_attr_arr[$attr_nm]);
} else {
return(NULL);
}
}
function getAttrArr()
{
return($this->_attr_arr);
}
function getParentId()
{
return($this->parent_id);
}
function getParentNode()
{
return($this->_parent_node);
}
function getChild($id)
{
if (isset($this->_child_arr[$id])) {
return($this->_child_arr[$id]);
} else {
return(FALSE);
}
}
function getFirstChild()
{
$id_arr = array_keys($this->_child_arr);
$num_child = count($id_arr);
if ($num_child > 0) {
return($this->_child_arr[$id_arr[0]]);
} else {
return(FALSE);
}
}
function getLastChild()
{
$id_arr = array_keys($this->_child_arr);
$num_child = count($id_arr);
if ($num_child > 0) {
return($this->_child_arr[$id_arr[$num_child - 1]]);
} else {
return(FALSE);
}
}
function getChildByIdx($idx)
{
$id_arr = array_keys($this->_child_arr);
if (isset($this->_child_arr[$id_arr[$idx]])) {
return($this->_child_arr[$id_arr[$idx]]);
} else {
return(FALSE);
}
}
function getNumChild()
{
return(count($this->_child_arr));
}
function removeChild($id)
{
unset($this->_child_arr[$id]);
}
function removeChildByIdx($idx)
{
$key_arr = array_keys($this->_child_arr);
unset($this->_child_arr[$key_arr[$idx]]);
}
function removeFirstChild()
{
$key_arr = array_keys($this->_child_arr);
unset($this->_child_arr[$key_arr[0]]);
}
function removeLastChild()
{
$key_arr = array_keys($this->_child_arr);
unset($this->_child_arr[$key_arr[count($key_arr)-1]]);
}
function dumpXML($indent_str = "\t")
{
$attr_txt = $this->_dumpAttr();
$name = $this->_dumpName();
$xmlns = $this->_dumpXmlns();
$lvl = $this->_getCurrentLevel();
$indent = str_pad('',$lvl,$indent_str);
if ($this->_mt_elem_flg) {
$tag = "$indent<$name$xmlns$attr_txt />";
return($tag);
} else {
$key_arr = array_keys($this->_child_arr);
$num_child = count($key_arr);
$tag = "$indent<$name$xmlns$attr_txt>$this->_content";
for ($i = 0;$i < $num_child;$i++) {
$node = $this->_child_arr[$key_arr[$i]];
$child_txt = $node->dumpXML($indent_str);
$tag .= "\n$child_txt";
}
$tag .= ($num_child > 0 ? "\n$indent</$name>" : "</$name>");
return($tag);
}
}
function _dumpAttr()
{
$id_arr = array_keys($this->_attr_arr);
$id_arr_cnt = count($id_arr);
$attr_txt = '';
for($i = 0;$i < $id_arr_cnt;$i++) {
$key = $id_arr[$i];
$attr_txt .= " $key=\"{$this->_attr_arr[$key]}\"";
}
return($attr_txt);
}
function _dumpName()
{
$alias = $this->getNamespaceAlias();
if ($alias == '') {
return($this->getName());
} else {
return("$alias:" . $this->getName());
}
}
function _dumpXmlns()
{
$nmspc = $this->getNamespace();
$alias = $this->getNamespaceAlias();
if ($nmspc != '') {
if ($alias == '') {
return(" xmlns=\"" . $nmspc . "\"");
} else {
return(" xmlns:$alias=\"" . $nmspc . "\"");
}
} else {
return('');
}
}
function _getCurrentLevel()
{
if ($this->_parent_id === FALSE) {
return(0);
} else {
$node = $this->getParentNode();
$lvl = $node->_getCurrentLevel();
$lvl++;
return($lvl);
}
}
}
class MathMLNode extends XMLNode
{
function MathMLNode($id = NULL)
{
parent::XMLNode($id);
}
function removeBrackets()
{
if ($this->_name == 'mrow') {
if ($c_node_0 = $this->getFirstChild()) {
$c_node_0->isLeftBracket() ? $this->removeFirstChild() : 0;
}
if ($c_node_0 = $this->getLastChild()) {
$c_node_0->isRightBracket() ? $this->removeLastChild() : 0;
}
}
}
function isLeftBracket()
{
switch ($this->_content) {
case '{':
case '[':
case '(':
return(TRUE);
break;
}
return(FALSE);
}
function isRightBracket()
{
switch ($this->_content) {
case '}':
case ']':
case ')':
return(TRUE);
break;
}
return(FALSE);
}
}
class ASCIIMathPHP
{
var $_expr;
var $_curr_expr;
var $_prev_expr;
var $_symbol_arr;
var $_node_arr;
var $_node_cntr;
function ASCIIMathPHP($symbol_arr,$expr = NULL)
{
$this->_symbol_arr = $symbol_arr;
if (isset($expr)) {
$this->setExpr($expr);
}
}
/**
* Returns an empty node (containing a non-breaking space) 26-Apr-2006
*
* Used when an expression is incomplete
*
* @return object
*
* @access private
*/
function emptyNode()
{
$tmp_node = $this->createNode();
$tmp_node->setName('mn');
$tmp_node->setContent('&#' . hexdec('200B') . ';');
return $tmp_node;
}
function pushExpr($prefix) // 2005-06-11 wes
{
$this->_curr_expr = $prefix . $this->_curr_expr;
}
function setExpr($expr)
{
$this->_expr = $expr;
$this->_curr_expr = $expr;
$this->_prev_expr = $expr;
$this->_node_arr = array();
$this->_node_cntr = 0;
}
function genMathML($attr_arr = NULL)
{
// <math> node
$node_0 = $this->createNode();
$node_0->setName('math');
$node_0->setNamepace('http://www.w3.org/1998/Math/MathML');
// <mstyle> node
if (isset($attr_arr)) {
$node_1 = $this->createNode();
$node_1->setName('mstyle');
$node_1->setAttrArr($attr_arr);
$node_arr = $this->parseExpr();
$node_1->addChildArr($node_arr);
$node_0->addChild($node_1);
} else {
$node_arr = $this->parseExpr();
$node_0->addChildArr($node_arr);
}
return TRUE;
}
/*
function mergeNodeArr(&$node_arr_0,&$node_arr_1)
{
$key_arr_0 = array_keys($node_arr_0);
$key_arr_1 = array_keys($node_arr_1);
$num_key_0 = count($key_arr_0);
$num_key_1 = count($key_arr_1);
$merge_arr = array();
for ($i = 0;$i < $num_key_0;$i++) {
$merge_arr[$key_arr_0[$i]] = $node_arr_0[$key_arr_0[$i]];
}
for ($j = 0;$j < $num_key_1;$i++) {
$merge_arr[$key_arr_1[$i]] = $node_arr_1[$key_arr_1[$i]];
}
return($merge_arr);
}
*/
//Broken out of parseExpr Sept 7, 2006 David Lippman for
//ASCIIMathML 1.4.7 compatibility
function parseIntExpr()
{
$sym_0 = $this->getSymbol();
$node_0 = $this->parseSmplExpr();
$sym = $this->getSymbol();
if (isset($sym['infix']) && $sym['input'] != '/') {
$this->chopExpr($sym['symlen']);
$node_1 = $this->parseSmplExpr();
if ($node_1 === FALSE) { //show box in place of missing argument
$node_1 = $this->emptyNode();//??
} else {
$node_1->removeBrackets();
}
// If 'sub' -- subscript
if ($sym['input'] == '_') {
$sym_1 = $this->getSymbol();
// If 'sup' -- superscript
if ($sym_1['input'] == '^') {
$this->chopExpr($sym_1['symlen']);
$node_2 = $this->parseSmplExpr();
$node_2->removeBrackets();
$node_3 = $this->createNode();
$node_3->setName(isset($sym_0['underover']) ? 'munderover' : 'msubsup');
$node_3->addChild($node_0);
$node_3->addChild($node_1);
$node_3->addChild($node_2);
$node_4 = $this->createNode();
$node_4->setName('mrow');
$node_4->addChild($node_3);
return $node_4;
} else {
$node_2 = $this->createNode();
$node_2->setName(isset($sym_0['underover']) ? 'munder' : 'msub');
$node_2->addChild($node_0);
$node_2->addChild($node_1);
return $node_2;
}
} else {
$node_2 = $this->createNode();
$node_2->setName($sym['tag']);
$node_2->addChild($node_0);
$node_2->addChild($node_1);
return($node_2);
}
} elseif ($node_0 !== FALSE) {
return($node_0);
} else {
return $this->emptyNode();
}
}
function parseExpr()
{
// Child/Fragment array
$node_arr = array();
// Deal whole expressions like 'ax + by + c = 0' etc.
do {
$sym_0 = $this->getSymbol();
$node_0 = $this->parseIntExpr();
$sym = $this->getSymbol();
// var_dump($sym);
if (isset($sym['infix']) && $sym['input'] == '/') {
$this->chopExpr($sym['symlen']);
$node_1 = $this->parseIntExpr();
if ($node_1 === FALSE) { //should show box in place of missing argument
$node_1 = $this->emptyNode();
continue;
}
$node_1->removeBrackets();
// If 'div' -- divide
$node_0->removeBrackets();
$node_2 = $this->createNode();
$node_2->setName($sym['tag']);
$node_2->addChild($node_0);
$node_2->addChild($node_1);
$node_arr[$node_2->getId()] = $node_2;
} elseif ($node_0 !== FALSE) {
$node_arr[$node_0->getId()] = $node_0;
}
} while (!isset($sym['right_bracket']) && $sym !== FALSE && $sym['output'] != '');
//var_dump($sym);
// Possibly to deal with matrices
if (isset($sym['right_bracket'])) {
$node_cnt = count($node_arr);
$key_node_arr = array_keys($node_arr);
if ($node_cnt > 1) {
$node_5 = $node_arr[$key_node_arr[$node_cnt-1]];
$node_6 = $node_arr[$key_node_arr[$node_cnt-2]];
} else {
$node_5 = FALSE;
$node_6 = FALSE;
}
// Dealing with matrices
if ($node_5 !== FALSE && $node_6 !== FALSE &&
$node_cnt > 1 &&
$node_5->getName() == 'mrow' &&
$node_6->getName() == 'mo' &&
$node_6->getContent() == ',') {
// Checking if Node 5 has a LastChild
if ($node_7 = $node_5->getLastChild()) {
$node_7_cntnt = $node_7->getContent();
} else {
$node_7_cntnt = FALSE;
}
// If there is a right bracket
if ($node_7 !== FALSE && ($node_7_cntnt == ']' || $node_7_cntnt == ')')) {
// Checking if Node 5 has a firstChild
if ($node_8 = $node_5->getFirstChild()) {
$node_8_cntnt = $node_8->getContent();
} else {
$node_8_cntnt = FALSE;
}
// If there is a matching left bracket
if ($node_8 !== FALSE &&
(($node_8_cntnt == '(' && $node_7_cntnt == ')' && $sym['output'] != '}') ||
($node_8_cntnt == '[' && $node_7_cntnt == ']'))) {
$is_mtrx_flg = TRUE;
$comma_pos_arr = array();
$i = 0;
while ($i < $node_cnt && $is_mtrx_flg) {
$tmp_node = $node_arr[$key_node_arr[$i]];
if($tmp_node_first = $tmp_node->getFirstChild()) {
$tnfc = $tmp_node_first->getContent();
} else {
$tnfc = FALSE;
}
if($tmp_node_last = $tmp_node->getLastChild()) {
$tnlc = $tmp_node_last->getContent();
} else {
$tnlc = FALSE;
}
if (isset($key_node_arr[$i+1])) {
$next_tmp_node = $node_arr[$key_node_arr[$i+1]];
$ntnn = $next_tmp_node->getName();
$ntnc = $next_tmp_node->getContent();
} else {
$ntnn = FALSE;
$ntnc = FALSE;
}
// Checking each node in node array for matrix criteria
if ($is_mtrx_flg) {
$is_mtrx_flg = $tmp_node->getName() == 'mrow' &&
($i == $node_cnt-1 || $ntnn == 'mo' && $ntnc == ',') &&
$tnfc == $node_8_cntnt && $tnlc == $node_7_cntnt;
}
if ($is_mtrx_flg) {
for ($j = 0;$j < $tmp_node->getNumChild();$j++) {
$tmp_c_node = $tmp_node->getChildByIdx($j);
if ($tmp_c_node->getContent() == ',') {
$comma_pos_arr[$i][] = $j;
}
}
}
if ($is_mtrx_flg && $i > 1) {
$cnt_cpan = isset($comma_pos_arr[$i]) ? count($comma_pos_arr[$i]) : NULL;
$cnt_cpap = isset($comma_pos_arr[$i-2]) ? count($comma_pos_arr[$i-2]) : NULL;
$is_mtrx_flg = $cnt_cpan == $cnt_cpap;
}
$i += 2;
}
// If the node passes the matrix tests
if ($is_mtrx_flg) {
$tab_node_arr = array();
for ($i = 0;$i < $node_cnt;$i += 2) {
$tmp_key_node_arr = array_keys($node_arr);
if (!($tmp_node = $node_arr[$tmp_key_node_arr[0]])) {
break;
}
$num_child = $tmp_node->getNumChild();
$k = 0;
$tmp_node->removeFirstChild();
$row_node_arr = array();
$row_frag_node_arr = array();
for ($j = 1;$j < ($num_child-1);$j++) {
if (isset($comma_pos_arr[$i][$k]) &&
$j == $comma_pos_arr[$i][$k]) {
$tmp_node->removeFirstChild();
$tmp_c_node = $this->createNode();
$tmp_c_node->setName('mtd');
$tmp_c_node->addChildArr($row_frag_node_arr);
$row_frag_node_arr = array();
$row_node_arr[$tmp_c_node->getId()] = $tmp_c_node;
$k++;
} else {
if ($tmp_c_node = $tmp_node->getFirstChild()) {
$row_frag_node_arr[$tmp_c_node->getId()] = $tmp_c_node;
$tmp_node->removeFirstChild();
}
}
}
$tmp_c_node = $this->createNode();
$tmp_c_node->setName('mtd');
$tmp_c_node->addChildArr($row_frag_node_arr);
$row_node_arr[$tmp_c_node->getId()] = $tmp_c_node;
if (count($node_arr) > 2) {
$tmp_key_node_arr = array_keys($node_arr);
unset($node_arr[$tmp_key_node_arr[0]]);
unset($node_arr[$tmp_key_node_arr[1]]);
}
$tmp_c_node = $this->createNode();
$tmp_c_node->setName('mtr');
$tmp_c_node->addChildArr($row_node_arr);
$tab_node_arr[$tmp_c_node->getId()] = $tmp_c_node;
}
$tmp_c_node = $this->createNode();
$tmp_c_node->setName('mtable');
$tmp_c_node->addChildArr($tab_node_arr);
if (isset($sym['invisible'])) {
$tmp_c_node->setAttr('columnalign','left');
}
$key_node_arr = array_keys($node_arr);
$tmp_c_node->setId($key_node_arr[0]);
$node_arr[$tmp_c_node->getId()] = $tmp_c_node;
}
}
}
}
$this->chopExpr($sym['symlen']);
if (!isset($sym['invisible'])) {
$node_7 = $this->createNode();
$node_7->setName('mo');
$node_7->setContent($sym['output']);
$node_arr[$node_7->getId()] = $node_7;
}
}
return($node_arr);
}
function parseSmplExpr()
{
$sym = $this->getSymbol();
if (!$sym || isset($sym['right_bracket'])) //return FALSE;
return $this->emptyNode();
$this->chopExpr($sym['symlen']);
// 2005-06-11 wes: add definition type support
if(isset($sym['definition'])) {
$this->pushExpr($sym['output']);
$sym = $this->getSymbol();
$this->chopExpr($sym['symlen']);
}
if (isset($sym['left_bracket'])) {
$node_arr = $this->parseExpr();
if (isset($sym['invisible'])) {
$node_0 = $this->createNode();
$node_0->setName('mrow');
$node_0->addChildArr($node_arr);
return($node_0);
} else {
$node_0 = $this->createNode();
$node_0->setName('mo');
$node_0->setContent($sym['output']);
$node_1 = $this->createNode();
$node_1->setName('mrow');
$node_1->addChild($node_0);
$node_1->addChildArr($node_arr);
return($node_1);
}
} elseif (isset($sym['unary'])) {
if ($sym['input'] == 'sqrt') {
$node_0 = $this->parseSmplExpr();
$node_0->removeBrackets();
$node_1 = $this->createNode();
$node_1->setName($sym['tag']);
$node_1->addChild($node_0);
return($node_1);
} elseif (isset($sym['func'])) { //added 2006-9-7 David Lippman
$expr = ltrim($this->getCurrExpr());
$st = $expr{0};
$node_0 = $this->parseSmplExpr();
//$node_0->removeBrackets();
if ($st=='^' || $st == '_' || $st=='/' || $st=='|' || $st==',') {
$node_1 = $this->createNode();
$node_1->setName($sym['tag']);
$node_1->setContent($sym['output']);
$this->setCurrExpr($expr);
return($node_1);
} else {
$node_1 = $this->createNode();
$node_1->setName('mrow');
$node_2 = $this->createNode();
$node_2->setName($sym['tag']);
$node_2->setContent($sym['output']);
$node_1->addChild($node_2);
$node_1->addChild($node_0);
return($node_1);
}
} elseif ($sym['input'] == 'text' || $sym['input'] == 'mbox' || $sym['input'] == '"') {
$expr = ltrim($this->getCurrExpr());
if ($sym['input']=='"') {
$end_brckt = '"';
$txt = substr($expr,0,strpos($expr,$end_brckt));
} else {
switch($expr{0}) {
case '(':
$end_brckt = ')';
break;
case '[':
$end_brckt = ']';
break;
case '{':
$end_brckt = '}';
break;
default:
$end_brckt = chr(11); // A character that will never be matched.
break;
}
$txt = substr($expr,1,strpos($expr,$end_brckt)-1);
}
//$txt = substr($expr,1,strpos($expr,$end_brckt)-1);
$len = strlen($txt);
$node_0 = $this->createNode();
$node_0->setName('mrow');
if ($len > 0) {
if ($txt{0} == " ") {
$node_1 = $this->createNode();
$node_1->setName('mspace');
$node_1->setAttr('width','1ex');
$node_0->addChild($node_1);
}
$node_3 = $this->createNode();
$node_3->setName($sym['tag']);
$node_3->setContent(trim($txt));
$node_0->addChild($node_3);
if ($len > 1 && $txt{$len-1} == " ") {
$node_2 = $this->createNode();
$node_2->setName('mspace');
$node_2->setAttr('width','1ex');
$node_0->addChild($node_2);
}
$this->chopExpr($len+2);
}
return($node_0);
} elseif (isset($sym['acc'])) {
$node_0 = $this->parseSmplExpr();
$node_0->removeBrackets();
$node_1 = $this->createNode();
$node_1->setName($sym['tag']);
$node_1->addChild($node_0);
$node_2 = $this->createNode();
$node_2->setName('mo');
$node_2->setContent($sym['output']);
$node_1->addChild($node_2);
return($node_1);
} else {
// Font change commands -- to complete
}
} elseif (isset($sym['binary'])) {
$node_arr = array();
$node_0 = $this->parseSmplExpr();
$node_0->removeBrackets();
$node_1 = $this->parseSmplExpr();
$node_1->removeBrackets();
/* 2005-06-05 wes: added stackrel */
if ($sym['input'] == 'root' || $sym['input'] == 'stackrel') {
$node_arr[$node_1->getId()] = $node_1;
$node_arr[$node_0->getId()] = $node_0;
} elseif ($sym['input'] == 'frac') {
$node_arr[$node_0->getId()] = $node_0;
$node_arr[$node_1->getId()] = $node_1;
}
$node_2 = $this->createNode();
$node_2->setName($sym['tag']);
$node_2->addChildArr($node_arr);
return($node_2);
} elseif (isset($sym['infix'])) {
$node_0 = $this->createNode();
$node_0->setName('mo');
$node_0->setContent($sym['output']);
return($node_0);
} elseif (isset($sym['space'])) {
$node_0 = $this->createNode();
$node_0->setName('mrow');
$node_1 = $this->createNode();
$node_1->setName('mspace');
$node_1->setAttr('width',$sym['space']);
$node_2 = $this->createNode();
$node_2->setName($sym['tag']);
$node_2->setContent($sym['output']);
$node_3 = $this->createNode();
$node_3->setName('mspace');
$node_3->setAttr('width',$sym['space']);
$node_0->addChild($node_1);
$node_0->addChild($node_2);
$node_0->addChild($node_3);
return($node_0);
} else {
// A constant
$node_0 = $this->createNode();
$node_0->setName($sym['tag']);
$node_0->setContent($sym['output']);
return($node_0);
}
// Return an empty node
return $this->emptyNode();
}
function getMathML()
{
$root = $this->_node_arr[0];
return($root->dumpXML());
}
function getCurrExpr()
{
return($this->_curr_expr);
}
function setCurrExpr($str)
{
$this->_curr_expr = $str;
}
function getExpr()
{
return($this->_expr);
}
function getPrevExpr()
{
return($this->_prev_expr);
}
function createNode()
{
$node = new MathMLNode($this->_node_cntr);
// $node->setNamespaceAlias('m');
$this->_node_arr[$this->_node_cntr] = $node;
$this->_node_cntr++;
return($node);
}
/**
* Gets the largest symbol in the expression (greedy). Changed from non-greedy 26-Apr-2006
*
* @parameter boolean[optional] Chop original string?
*
* @return mixed
*
* @access private
*/
function getSymbol($chop_flg = FALSE)
{
// Implemented a reverse symbol matcher.
// Instead of going front to back, it goes back to front. Steven 26-Apr-2006
$chr_cnt = strlen($this->_curr_expr);
if ($chr_cnt == 0) return FALSE;
for ($i = $chr_cnt; $i > 0; $i--) {
$sym_0 = substr($this->_curr_expr,0,$i);
// Reading string for numeric values
if (is_numeric($sym_0)) {
if ($chop_flg) $this->chopExpr($i);
return array('input'=>$sym_0, 'tag'=>'mn', 'output'=>$sym_0, 'symlen'=>$i);
} elseif (isset($this->_symbol_arr[$sym_0])) {
if ($chop_flg) $this->chopExpr($i);
$sym_arr = $this->_symbol_arr[$sym_0];
$sym_arr['symlen'] = $i;
return $sym_arr;
}
}
// Reading string for alphabetic constants and the minus sign
$char = $this->_curr_expr{0};
$len_left = $chop_flg ? $this->chopExpr(1) : strlen($this->_curr_expr)-1;
// Deals with expressions of length 1
if ($len_left == 0 && isset($this->_symbol_arr[$char])) {
$sym_arr = $this->_symbol_arr[$char];
$sym_arr['symlen'] = 1;
return $sym_arr;
} else {
$tag = preg_match('/[a-z]/i',$char) ? 'mi' : 'mo';
return array('input'=>$char, 'tag'=>$tag, 'output'=>$char, 'symlen'=>1);
}
}
function chopExpr($strlen)
{
$this->_prev_expr = $this->_curr_expr;
if ($strlen == strlen($this->_curr_expr)) {
$this->_curr_expr = '';
return(0);
} else {
$this->_curr_expr = ltrim(substr($this->_curr_expr,$strlen));
return(strlen($this->_curr_expr));
}
}
}
?>