嗨，所以我一直在努力制作我想要的图表，我已经非常接近了。
首先，我有应该在 YAXIS #1 上的股票投资组合的业绩数据……这很好。然后我想在 YAXIS #2 上做一个基准测试……线图有效，但比例很奇怪：
请注意它是如何从 50 开始到 10、15、20 等...问题是比例应该在 3400 到 3800 之间，因为这是我的数据范围。
这是我的代码：
<?php // content="text/plain; charset=utf-8"
require($_SERVER['DOCUMENT_ROOT'] . '/wp-blog-header.php');
require_once ('jpgraph.php');
require_once ('jpgraph_line.php');
require_once ('jpgraph_date.php');
require_once ('jpgraph_utils.inc.php');
// Get a dataset
$data = get_transient( 'daily_nav' );
$ydata = $data[1];
$xdata = $data[0];
$data2 = get_transient( 'CAC40_history' );
$ydata2 = array_reverse($data2[1]);
$xdata2 = array_reverse($data2[0]);
$dateUtils = new DateScaleUtils();
list($tickPositions, $minTickPositions) = DateScaleUtils::GetTicks($xdata);
// Setup a basic graph
$width=800; $height=500;
$graph = new Graph($width, $height);
$graph->SetScale('datlin');
$graph->SetYScale(0,'lin');
$graph->SetYScale(1,'lin');
$graph->SetMargin(60,20,40,60);
$graph->xaxis->SetPos('min');
$graph->xaxis->SetTickPositions($tickPositions,$minTickPositions);
// Setup the titles
$graph->title->SetFont(FF_GEORGIA,FS_NORMAL,16);
$graph->title->Set('Performance vs. CAC40');
$graph->subtitle->SetFont(FF_ARIAL,FS_ITALIC,10);
$graph->subtitle->Set('graphique journalier depuis la création en juin 2012');
// Setup the labels to be correctly format on the X-axis
$graph->xaxis->SetFont(FF_ARIAL,FS_NORMAL,8);
$graph->xaxis->SetLabelAngle(30);
// The second paramter set to 'true' will make the library interpret the
// format string as a date format. We use a Month + Year format m-d-Y
$graph->xaxis->SetLabelFormatString('m-Y',true);
// And then add line. We use two plots in order to get a
// more distinct border on the graph
$lp2 = new LinePlot($ydata,$xdata);
$lp2->SetColor('#71a7da');
$graph->Add($lp2);
$graph->xgrid->Show();
$graph->AddY(0,$lp2);
// second chart
$lp3 = new LinePlot($ydata2, $xdata2);
$lp3->SetColor('blue');
//$graph->Add($lp3);
//$graph->xgrid->Show();
$graph->AddY(1,$lp3);
// And send back to the client
$graph->Stroke();
?>
如果有人可以提供帮助，那就太好了，无法弄清楚这一点。谢谢