106 lines
3.8 KiB
PHP
106 lines
3.8 KiB
PHP
<?php
|
|
/*=======================================================================
|
|
// File: JPGRAPH_MESHINTERPOLATE.INC.PHP
|
|
// Description: Utility class to do mesh linear interpolation of a matrix
|
|
// Created: 2009-03-09
|
|
// Ver: $Id: jpgraph_meshinterpolate.inc.php 1709 2009-07-30 08:00:08Z ljp $
|
|
//
|
|
// Copyright (c) Asial Co. Ltd. (Asial USA) All rights reserved.
|
|
//========================================================================
|
|
*/
|
|
|
|
/**
|
|
* Utility function to do linear mesh interpolation
|
|
* @param $aDat Matrix to interpolate
|
|
* @param $aFactor Interpolation factor
|
|
*/
|
|
function doMeshInterpolate( &$aData, $aFactor ) {
|
|
$m = new MeshInterpolate();
|
|
$aData = $m->Linear($aData,$aFactor);
|
|
}
|
|
|
|
/**
|
|
* Utility class to interpolate a given data matrix
|
|
*
|
|
*/
|
|
class MeshInterpolate {
|
|
private $data = array();
|
|
|
|
/**
|
|
* Calculate the mid points of the given rectangle which has its top left
|
|
* corner at $row,$col. The $aFactordecides how many spliots should be done.
|
|
* i.e. how many more divisions should be done recursively
|
|
*
|
|
* @param $row Top left corner of square to work with
|
|
* @param $col Top left corner of square to work with
|
|
* $param $aFactor In how many subsquare should we split this square. A value of 1 indicates that no action
|
|
*/
|
|
function IntSquare( $aRow, $aCol, $aFactor ) {
|
|
if ( $aFactor <= 1 )
|
|
return;
|
|
|
|
$step = pow( 2, $aFactor-1 );
|
|
|
|
$v0 = $this->data[$aRow][$aCol];
|
|
$v1 = $this->data[$aRow][$aCol + $step];
|
|
$v2 = $this->data[$aRow + $step][$aCol];
|
|
$v3 = $this->data[$aRow + $step][$aCol + $step];
|
|
|
|
$this->data[$aRow][$aCol + $step / 2] = ( $v0 + $v1 ) / 2;
|
|
$this->data[$aRow + $step / 2][$aCol] = ( $v0 + $v2 ) / 2;
|
|
$this->data[$aRow + $step][$aCol + $step / 2] = ( $v2 + $v3 ) / 2;
|
|
$this->data[$aRow + $step / 2][$aCol + $step] = ( $v1 + $v3 ) / 2;
|
|
$this->data[$aRow + $step / 2][$aCol + $step / 2] = ( $v0 + $v1 + $v2 + $v3 ) / 4;
|
|
|
|
$this->IntSquare( $aRow, $aCol, $aFactor-1 );
|
|
$this->IntSquare( $aRow, $aCol + $step / 2, $aFactor-1 );
|
|
$this->IntSquare( $aRow + $step / 2, $aCol, $aFactor-1 );
|
|
$this->IntSquare( $aRow + $step / 2, $aCol + $step / 2, $aFactor-1 );
|
|
}
|
|
|
|
/**
|
|
* Interpolate values in a matrice so that the total number of data points
|
|
* in vert and horizontal axis are $aIntNbr more. For example $aIntNbr=2 will
|
|
* make the data matrice have tiwce as many vertical and horizontal dta points.
|
|
*
|
|
* Note: This will blow up the matrcide in memory size in the order of $aInNbr^2
|
|
*
|
|
* @param $ &$aData The original data matricde
|
|
* @param $aInNbr Interpolation factor
|
|
* @return the interpolated matrice
|
|
*/
|
|
function Linear( &$aData, $aIntFactor ) {
|
|
$step = pow( 2, $aIntFactor-1 );
|
|
|
|
$orig_cols = count( $aData[0] );
|
|
$orig_rows = count( $aData );
|
|
// Number of new columns/rows
|
|
// N = (a-1) * 2^(f-1) + 1
|
|
$p = pow( 2, $aIntFactor-1 );
|
|
$new_cols = $p * ( $orig_cols - 1 ) + 1;
|
|
$new_rows = $p * ( $orig_rows - 1 ) + 1;
|
|
|
|
$this->data = array_fill( 0, $new_rows, array_fill( 0, $new_cols, 0 ) );
|
|
// Initialize the new matrix with the values that we know
|
|
for ( $i = 0; $i < $new_rows; $i++ ) {
|
|
for ( $j = 0; $j < $new_cols; $j++ ) {
|
|
$v = 0 ;
|
|
if ( ( $i % $step == 0 ) && ( $j % $step == 0 ) ) {
|
|
$v = $aData[$i / $step][$j / $step];
|
|
}
|
|
$this->data[$i][$j] = $v;
|
|
}
|
|
}
|
|
|
|
for ( $i = 0; $i < $new_rows-1; $i += $step ) {
|
|
for ( $j = 0; $j < $new_cols-1; $j += $step ) {
|
|
$this->IntSquare( $i, $j, $aIntFactor );
|
|
}
|
|
}
|
|
|
|
return $this->data;
|
|
}
|
|
}
|
|
|
|
?>
|