我有一个Google图表折线图,我想在其上显示趋势线,但它没有显示。
数据是从数据库中获取的,而javascript是由PHP生成的,但生成的javascript如下所示:
<script type="text/javascript" src="https://www.google.com/jsapi"></script>
<script type="text/javascript">
// Load the Visualization API and the piechart package.
google.load('visualization', '1.0', {'packages':['corechart']});
// Set a callback to run when the Google Visualization API is loaded.
google.setOnLoadCallback(drawChart);
// Callback that creates and populates a data table,
// instantiates the pie chart, passes in the data and
// draws it.
function drawChart() {
var dataS = new google.visualization.DataTable();
dataS.addColumn('string', 'Dag');
dataS.addColumn('number', 'Poäng');
dataS.addRows([
['1', 32],
['2', 37],
['3', 37],
['4', 40],
['5', 31],
['6', 38],
['7', 28],
['8', 34],
['9', 41],
['10', 41],
]);
var optionsS = {
title: '',
legend: 'none',
hAxis: {title: 'Serie'},
vAxis: {title: 'Poäng'},
pointSize: 4,
trendlines: { 0: {} }
};
// Instantiate and draw our chart, passing in some options.
var chart = new google.visualization.LineChart(document.getElementById('chart_div_series'));
chart.draw(dataS, optionsS);
}
</script>
该脚本主要来自Google图表示例中的copypaste。图表工作正常,但趋势线未显示。有什么想法吗?
答案 0 :(得分:22)
您必须拥有连续的域轴(类型“数字”,“日期”,“日期时间”或“timeofday”)才能使用趋势线。通过将第一列设置为“字符串”类型(并用字符串填充),您将禁用趋势线。切换到“数字”类型列,趋势线将起作用:
var dataS = new google.visualization.DataTable();
dataS.addColumn('number', 'Dag');
dataS.addColumn('number', 'Poäng');
dataS.addRows([
[1, 32],
[2, 37],
[3, 37],
[4, 40],
[5, 31],
[6, 38],
[7, 28],
[8, 34],
[9, 41],
[10, 41]
]);