数据研究脚本
该数据研究工具由单个脚本（ explore.php）构成，该脚本调用 SimpleLinearRegressionHTML 类和 JpGraph 库的方法。
该脚本使用了简单的处理逻辑。该脚本的第一部分对所提交的表单数据执行基本验证。如果这些表单数据通过验证，则执行该脚本的第二部分。
该脚本的第二部分所包含的代码用于分析数据，并以 HTML 和图形格式显示汇总结果。 清单 4中显示了 explore.php脚本的基本结构：
清单 4. explore.php 的结构
＜?php
// explore.php
if (!empty($x_values)) {
$X = explode(",", $x_values);
$numX = count($X);
}
if (!empty($y_values)) {
$Y = explode(",", $y_values);
$numY = count($Y);
}
// display entry data entry form if variables not set
if ( (empty($title)) OR (empty($x_name)) OR (empty($x_values)) OR
(empty($y_name)) OR (empty($conf_int)) OR (empty($y_values)) OR
($numX != $numY) ) {
// Omitted code for displaying entry form
} else {
include_once "slr/SimpleLinearRegressionHTML.php";
$slr = new SimpleLinearRegressionHTML($X, $Y, $conf_int);
echo "＜h2＞$title＜/h2＞";
$slr-＞showTableSummary($x_name, $y_name);
echo "＜br＞＜br＞";
$slr-＞showAnalysisOfVariance();
echo "＜br＞＜br＞";
$slr-＞showParameterEstimates($x_name, $y_name);
echo "＜br＞";
$slr-＞showFormula($x_name, $y_name);
echo "＜br＞＜br＞";
$slr-＞showRValues($x_name, $y_name);
echo "＜br＞";
include ("jpgraph/jpgraph.php");
include ("jpgraph/jpgraph_scatter.php");
include ("jpgraph/jpgraph_line.php");
// The code for displaying the graphics is inline in the
// explore.php script. The code for these two line plots
// finishes off the script:
// Omitted code for displaying scatter plus line plot
// Omitted code for displaying residuals plot
}
?＞
