I'm trying to draw a Google bar chart with a logarithmic scale. However, it starts at 1, not 0. This looks like bad data because entries with one value are rendered with no bar. I tried settingminValue to zero, but it won't seem to honor that when logScale is true.
Is it even possible to have a logarithmic scale that starts at zero?
Here's some code that reproduces the problem on the visualization playground:
function drawVisualization() {
// Create and populate the data table.
var data = new google.visualization.DataTable();
data.addColumn('number', 'Age');
data.addColumn('number', 'Weight');
data.addRows(6);
data.setValue(0, 0, 8);
data.setValue(0, 1, 12);
data.setValue(1, 0, 4);
data.setValue(1, 1, 5.5);
data.setValue(2, 0, 11);
data.setValue(2, 1, 14);
data.setValue(3, 0, 4);
data.setValue(3, 1, 4.5);
data.setValue(4, 0, 3);
data.setValue(4, 1, 3.5);
data.setValue(5, 0, 6.5);
data.setValue(5, 1, 7);
// Create and draw the visualization.
new google.visualization.BarChart(document.getElementById('visualization')).
draw(data,
{title:"Yearly Coffee Consumption by Country",
width:600, height:400,
vAxis: {title: "Year"},
hAxis: {title: "Cups", minValue: 0, logScale: true}}
);
}
You cannot have 0 (or a negative value) on a logarithmic scale because log(0) = -infinity. You can however set the the minValue to a low value, like 0.1, 0.001, or whatever suits your data.
This is rather old, but came up in a google search, so I'll leave this pointer here...there is an undocumented option "scaleType": "mirrorLog" that supports negative/zero values in a log scale (by switching to linear for small values).
See-also https://code.google.com/p/google-visualization-api-issues/issues/detail?id=984
Related
When I create simple line plot/chart using Apache Echarts I also can add built-in data scaling mechanism: dataZoom. It reaches its main goal, but there is a question to scaled data representation, made by dataZoom. By default, dataZoom doesn't take into account the chart scale limits ticks or/and the minimum and maximum allowable values (range of a function, represented by the plot). Instead, the thumbnail of the chart is drawn on the specific value range passed to the plot in series section. In addition, everytime a small indent is added from the minimum and maximum values to the borders of the graphic element.
As a result, the representation of the visualised data looks inconsistent with reality: null is not null, max is not max (because they don't match the lower and higher bounds of the coordinate area of the thumbnail plot, respectively), the amplitude of the chart fluctuations does not correspond to the scale of real data fluctuations.
Screenshot
Is there a way (documented or undocumented) to remove the indents and force the plot to use the minimum and maximum values allowed for the yAxis ticks?
I drawn a small example, it may be pasted to Echarts online editor.
let x = [];
let y = [];
let scaled = [];
/*y = [
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 300, 300,
10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 0, 0, 0, 0, 0, 0
];*/
for (let i = 1; i < 300; i++) {
x.push(i);
element = Math.random() * 40 + 50;
y.push(element);
scaled.push(element * 6 - 250);
}
option = {
xAxis: {
data: x
},
yAxis: {
min: 0,
max: 300
},
dataZoom: [
{
start: 50,
end: 58.5
}
],
series: [
{
name: 'Fake Data',
type: 'line',
symbol: 'none',
data: y
},
{
name: 'Simulated Scaling',
type: 'line',
symbol: 'none',
lineStyle: {
opacity: 0.3
},
data: scaled
}
]
};
As you can see, the magnitude of the fluctuations of the graph, drawn by dataZoom doesn't correspond rather to the main data, but to some kind of artificial transformation of them (light green graph). Then try to comment 11st line and uncomment lines from 4 to 7. At the start of the plot you'll see main graph touching y zero line, but not on the thumbnail.
I didn't find any params for dataZoom that make them to look like expected.
Can some one help me to draw hyperbola using JavaScript.As i am able to draw parabola now. but in hyperbola getting confused. For parabola i used:
function drawParabola(y)
{
myGraph.context.clearRect(0, 0, myGraph.canvas.width, myGraph.canvas.height);
myGraph = new Graph({
canvasId: "myCanvas",
minX: -10,
minY: -10,
maxX: 10,
maxY: 10,
unitsPerTick: 1
});
myGraph.drawEquation(function(x){
return y*x*x;
}, "red", 2);
}
Please suggest me for hyperbola
I have the following code to draw candlestick visualization. But the visualization is not generated. I am unable to trace error using Error Console!.
<script type="text/javascript" src="http://www.google.com/jsapi"></script>
<script type="text/javascript">
google.load('visualization', '1', {packages: ['corechart']});
function drawVisualization() {
// Populate the data table.
var data = new google.visualization.DataTable();
data.addColumn('string', 'Date');
data.addColumn('number');
data.addColumn('number');
data.addColumn('number');
data.addColumn('number');
data.setValue(0, 0,'Mon');
data.setValue(0, 1, '2');
data.setValue(0,2,'6');
data.setValue(0,3,'8');
data.setValue(0,4,'10');
data.setValue(1, 0,'Mon');
data.setValue(1, 1, '2');
data.setValue(1,2,'6');
data.setValue(1,3,'8');
data.setValue(1,4,'10');
// Draw the chart.
var chart = new google.visualization.CandlestickChart(document.getElementById('visualization'));
chart.draw(data, {legend:'none', width:600, height:400});
}
google.setOnLoadCallback(drawVisualization);
</script>
Any Help Greatly Appreciated!
Thank You!
Two problems:
1 - You need to add rows to the table before you try and set their values.
2 - Values for index 1,2,3 and 4 have to be numbers instead of strings since Columns 1,2,3,4 are of a numeric type
...
// Populate the data table.
var data = new google.visualization.DataTable();
data.addColumn('string', 'Date');
data.addColumn('number');
data.addColumn('number');
data.addColumn('number');
data.addColumn('number');
//Add new rows first
data.addRow();
data.addRow();
data.setValue(0, 0, 'Mon');
data.setValue(0, 1, 2);
data.setValue(0, 2, 6);
data.setValue(0, 3, 8);
data.setValue(0, 4, 10);
data.setValue(1, 0, 'Mon');
data.setValue(1, 1, 2);
data.setValue(1, 2, 6);
data.setValue(1, 3, 8);
data.setValue(1, 4, 10);
// Draw the chart.
...
Here is a working example
http://jsfiddle.net/WcKFf/2/
http://code.google.com/apis/chart/
<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', {'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() {
// Create our data table.
var data = new google.visualization.DataTable();
data.addColumn('string', 'date');
data.addColumn('number', 'Views');
data.addColumn('number', 'People');
data.addRows([
<?php echo $analytics; ?>
]);
// Instantiate and draw our chart, passing in some options.
var chart = new google.visualization.AreaChart(document.getElementById('Analytics-Visualization'));
chart.draw(data, {lineWidth:3, pointSize:8, width: 745, height: 240,chartArea:{left:20,top:20,width:640}});
}
</script>
lets say when we do this it does this
to
maybe using the listener stuff ?
For custom tooltips, add the tooltip as an extra column:
function drawVisualization() {
data = new google.visualization.DataTable()
data.addColumn('string', 'Date');
data.addColumn('number');
data.addColumn({type:'string',role:'tooltip'});
data.addRow();
base = 10;
data.setValue(0, 0, 'Datapoint1');
data.setValue(0, 1, base++);
data.setValue(0, 2, " This is my tooltip1 ");
data.addRow();
data.setValue(1, 0, 'Datapoint2');
data.setValue(1, 1, base++);
data.setValue(1, 2, "This is my second tooltip2");
// Draw the chart.
var chart = new google.visualization.BarChart(document.getElementById('visualization'));
chart.draw(data, {legend:'none', width:600, height:400});
}
#Adam; If you want to edit text then check this http://code.google.com/apis/ajax/playground/?type=visualization#pie_chart
you can change your code from here
function drawVisualization() {
// Create and populate the data table.
var data = new google.visualization.DataTable();
data.addColumn('string', 'Task');
data.addColumn('number', 'Hours per Day');
data.addRows(5);
data.setValue(0, 0, 'Work');
data.setValue(0, 1, 11);
data.setValue(1, 0, 'Eat');
data.setValue(1, 1, 2);
data.setValue(2, 0, 'Commute');
data.setValue(2, 1, 2);
data.setValue(3, 0, 'Watch TV');
data.setValue(3, 1, 2);
data.setValue(4, 0, 'Sleep');
data.setValue(4, 1, 7);
and if you want your custom tooltip you have to use javascript for these
http://code.google.com/p/gvtooltip/
http://informationandvisualization.de/blog/tooltips-google-chart-api
Watch the CPU and memory gauges for a second. They move dynamically.
The example code shown below does not move the gauges like that (or at least when I tried it in my own project.)
How do I to get it moving dynamically like that?
(Also, will these gauges slow down my site connecting to Google? On the other hand, will it bring up my rankings?)
The example code and the actual demo are different. Try this instead:
<html>
<head>
<script type='text/javascript' src='http://www.google.com/jsapi'></script>
<script type='text/javascript'>
google.load('visualization', '1', {packages:['gauge']});
google.setOnLoadCallback(drawChart);
</script>
</head>
<body>
<div id='chart_div'></div>
<script type="text/javascript">
function Timer(){this.t={};this.tick=function(a,b){this.t[a]=[(new Date).getTime(),b]};this.tick("start")}var loadTimer=new Timer;window.jstiming={Timer:Timer,load:loadTimer};if(window.external&&window.external.pageT)window.jstiming.pt=window.external.pageT;if(window.jstiming)window.jstiming.report=function(g,d){var c="";if(window.jstiming.pt){c+="&srt="+window.jstiming.pt;delete window.jstiming.pt}if(window.external&&window.external.tran)c+="&tran="+window.external.tran;var a=g.t,h=a.start;delete a.start;var i=[],e=[];for(var b in a){if(b.indexOf("_")==0)continue;var f=a[b][1];if(f)a[f][0]&&e.push(b+"."+(a[b][0]-a[f][0]));else h&&i.push(b+"."+(a[b][0]-h[0]))}if(d)for(var j in d)c+="&"+j+"="+d[j];(new Image).src=["http://csi.gstatic.com/csi?v=3","&s=gviz&action=",g.name,e.length?"&it="+e.join(",")+c:c,"&rt=",i.join(",")].join("")};
</script>
<script type="text/javascript">
var csi_timer = new window.jstiming.Timer();
csi_timer.name = 'docs_gauge';
google.setOnLoadCallback(drawChart);
function drawChart() {
csi_timer.tick('load');
var data = new google.visualization.DataTable();
data.addColumn('string', 'Label');
data.addColumn('number', 'Value');
data.addRows(3);
data.setValue(0, 0, 'Memory');
data.setValue(0, 1, 80);
data.setValue(1, 0, 'CPU');
data.setValue(1, 1, 55);
data.setValue(2, 0, 'Network');
data.setValue(2, 1, 68);
csi_timer.tick('data');
var chart = new google.visualization.Gauge(document.getElementById('chart_div'));
csi_timer.tick('new');
var options = {width: 400, height: 120, redFrom: 90, redTo: 100,
yellowFrom:75, yellowTo: 90, minorTicks: 5};
chart.draw(data, options);
csi_timer.tick('draw');
window.jstiming.report(csi_timer);
setInterval(function() {
data.setValue(0, 1, 40 + Math.round(60 * Math.random()));
chart.draw(data, options);
}, 13000);
setInterval(function() {
data.setValue(1, 1, 40 + Math.round(60 * Math.random()));
chart.draw(data, options);
}, 5000);
setInterval(function() {
data.setValue(2, 1, 60 + Math.round(20 * Math.random()));
chart.draw(data, options);
}, 26000);
}
</script>
</body>
</html>
Their demo uses a pseudo random number generator to update the graph. It's a little misleading.
I draw the initial chart using their code and then use an ajax call to fetch the updated data as a json string - from php. Then I populate the data table and update the chart with jQuery/javascript. I haven't gotten around to making a full tutorial yet b/c it's not ready for production...
The hardest part is getting your data formatted correctly on the server-side and feeding ajax without blowing up the browser. The code appears to be really fast and when you're monitoring a webserver you kinda want the image rendering to be done somewhere else. It works but, at this point, it's still not completely browser agnostic - which is why I chose to use re-write in jQuery.
As far as I know, your page rankings are unrelated...
All of the solutions are using random generated number to animate the gauge for demo. What if you want to show a real value AND animate it at the same time?
Here is the solution:
Code it yourself on JSFiddle
function isEven(n) {
return n % 2 == 0;// true|false
}
google.charts.load('current', {'packages':['gauge']});
google.charts.setOnLoadCallback(drawChart);
function drawChart() {
var data = google.visualization.arrayToDataTable([
['Label', 'Value'],
['Memory', 80],
['CPU', 55],
['Network', 68]
]);
var options = {
width: 400, height: 120,
redFrom: 90, redTo: 100,
yellowFrom:75, yellowTo: 90,
minorTicks: 5
};
var chart = new google.visualization.Gauge(document.getElementById('chart_div'));
chart.draw(data, options);
// Animate Gauges: (ArrayNum(start:0), ColumnInThatArray(start:0), NewValue)
// OR in anoher words(rowIndex, columnIndex, NewValue)
setInterval(function() {
var chartValue = data.getValue(0, 1);
if (isEven(chartValue)){
data.setValue(0, 1, (chartValue + 5));
} else {
data.setValue(0, 1, (chartValue - 5));
}
chart.draw(data, options);
}, 450);// milisecond
setInterval(function() {
var chartValue = data.getValue(1, 1);
if (isEven(chartValue)){
data.setValue(1, 1, (chartValue + 1));
} else {
data.setValue(1, 1, (chartValue - 1));
}
chart.draw(data, options);
}, 600);// milisecond
setInterval(function() {
var chartValue = data.getValue(2, 1);
if (isEven(chartValue)){
data.setValue(2, 1, (chartValue + 3));
} else {
data.setValue(2, 1, (chartValue - 3));
}
chart.draw(data, options);
}, 1000);// milisecond
}