timeline yAxis format with minutes:seconds only - highcharts

Question

I want to chart (line) a swimmer competition times over several meets.
For the series data I use the php code :
$datetime1=date('Y, m, d', strtotime($performances['PERF_DATE']."-1 month"));
$datetime2='Date.UTC('.$datetime1.')';
$chrono=strtotime($performances['PERF_DATE']);
$data[] = "[$datetime2, $chrono]";
The xAxis timeline is for swim meet dates :
xAxis: {
type: 'datetime',
dateTimeLabelFormats: {
day: '%d/%m/%Y'}
The yAxis timeline is for the race times :
yAxis: {
title : { text :'chronos'},
type: 'datetime', //y-axis will be in milliseconds
dateTimeLabelFormats: { //force all formats to be minute:second
second: '%M:%S',
minute: '%M:%S'
},
min: 0
}
The xAxis timeline works perfectly.
But I have a format issue with the yAxis: I cannot display the times in mm:ss format.
I'm using mysql 5.6.4 and the race times (PERF_TIME) are stored in type time(2) column , i.e. including 2 fractions of a second.
Race dates (PERF_DATE) are stored in type datetime column.
For example, $performances['PERF_DATE'] in a php generated table will display : 00:01:33.91.
But in Highcharts, on the yAxis, the value will be 16.Jan, and on the plot label it will show the value 1371333600. I guess those are microseconds.
I assume I need to apply the correct time format function on $chrono=strtotime($performances['PERF_DATE']);
Can someone help me with this ?
Thanks a lot.

Answer 1

Could you show your data output? For me it works fine, see: http://jsfiddle.net/Fusher/pQ5EC/12/ Make sure, your y-values are timestamps in milliseconds too.
$('#container').highcharts({
chart: {
type: 'column'
},
xAxis: {
type: 'datetime'
},
yAxis: {
type: 'datetime'
},
series: [{
name: 'Temperatures',
pointStart: new Date().getTime(),
pointInterval: 24 * 3600 * 1000,
data: [1.5 * 60 * 1000,1.2 * 60 * 1000,2.5 * 60 * 1000,1.9 * 60 * 1000,],
}]
});

Answer 2

Apologies, I did respond earlier but my answer was not saved by the system --- apparently there's an 8 hour black-out period where the author cannot answer his own question.
I figured it out:
my times are formated hh:mm:ss.00 in mysql. I thgouht there was a function to easily convert mysql time format into milliseconds format, but apparently there's none.
So I manually "explode" the time into milliseconds, using the code:
extract($performances);
//converts date from 2012-01-10 (mysql date format) to the format Highcharts understands 2012, 1, 10
$datetime1=date('Y, m, d', strtotime($performances['PERF_DATE']."-1 month"));
//getting the date into the required format for pushing the Data into the Series
$datetime2='Date.UTC('.$datetime1.')';
// value is in format hh:mm:ss.00
$chrono1=$performances['PERF_TIME'];
// explodes value in mn, sec and microseconds
sscanf($chrono1,"%d:%d:%d.%d",$hours,$minutes,$seconds,$milliseconds);
// calculate total of milliseconds
$chrono=$seconds * 1000 + $minutes * 60 * 1000 + $milliseconds * 10;
$data[] = "[$datetime2, $chrono]";
Maybe there's a cleaner way? But I can now feed $data to Highcharts and it works perfectly.
Thanks.