dygraphs
Version:
dygraphs is a fast, flexible open source JavaScript charting library.
83 lines (72 loc) • 3.06 kB
JavaScript
/*global Gallery,Dygraph,data */
//galleryActive=false
Gallery.register(
'number-format',
{
name: 'Number formatting',
setup: function(parent) {
parent.innerHTML =
"<p>The default formatting mimics printf with %.<i>p</i>g where <i>p</i> is" +
" the precision to use. It turns out that JavaScript's toPrecision()" +
" method is almost but not exactly equal to %g; they differ for values" +
" with small absolute values (10^-1 to 10^-5 or so), with toPrecision()" +
" yielding strings that are longer than they should be (i.e. using fixed" +
" point where %g would use exponential).</p>" +
"<p>This test is intended to check that our formatting works properly for a" +
" variety of precisions.</p>" +
"<p>Precision to use (1 to 21):" +
" <input type='text' id='p_input' size='20'></p>" +
"<p />" +
"<div id='content' style='font-family:Courier New,monospace'></div>";
},
run: function() {
// Helper functions for generating an HTML table for holding the test
// results.
var createRow = function(columnType, columns) {
var row = document.createElement('tr');
for (var i = 0; i < columns.length; i ++) {
var th = document.createElement(columnType);
var text = document.createTextNode(columns[i]);
th.appendChild(text);
row.appendChild(th);
}
return row;
};
var createHeaderRow = function(columns) {
return createRow('th', columns);
};
var createDataRow = function(columns) {
return createRow('td', columns);
};
var createTable = function(headerColumns, dataColumnsList) {
var table = document.createElement('table');
table.appendChild(createHeaderRow(headerColumns));
for (var i = 0; i < dataColumnsList.length; i++) {
table.appendChild(createDataRow(dataColumnsList[i]));
}
return table;
};
var updateTable = function() {
var headers = ['Dygraph.floatFormat()', 'toPrecision()',
'Dygraph.floatFormat()', 'toPrecision()'];
var numbers = [];
var p = parseInt(document.getElementById('p_input').value, 10);
for (var i = -10; i <= 10; i++) {
var n = Math.pow(10, i);
numbers.push([Dygraph.floatFormat(n, p),
n.toPrecision(p),
Dygraph.floatFormat(Math.PI * n, p),
(Math.PI * n).toPrecision(p)]);
}
// Check exact values of 0.
numbers.push([Dygraph.floatFormat(0.0, p),
(0.0).toPrecision(p)]);
var elem = document.getElementById('content');
elem.innerHTML = '';
elem.appendChild(createTable(headers, numbers));
};
document.getElementById('p_input').value = '4';
document.getElementById('p_input').onchange = updateTable;
updateTable();
}
});