I have two one dimensionaly arrays - each of the same length; temperature and seconds. To create a scatter graph, I need it in the form;
var data = [
[temperature[100],seconds[100]],
[temperature[99],seconds[99]],
[temperature[98],seconds[98]],
...
];
I can't seem to work out how to do it, and I seem to be asking the wrong questions in Google.
Loop backwards through the arrays and create new arrays from each pair of items:
var data = [];
for (var i = temperature.length - 1; i >= 0 ; i--) {
data.push([ temperature[i], seconds[i] ]);
}
temperature and seconds array should come first.
push is somewhat slower, but it makes for simpler code here. You can make it faster by creating the array with the final size, and by setting the items using the index instead of using push, but there is no dramatic difference. Arrays work a little different in various browsers, in Firefox for example it doesn't make any difference at all if you create the array with the final size or create an empty array and let it grow.
I think this the solution to your problem, though not tested.
data = [];
for(var i = 0, len = temperature.lengh - 1;i < len; i++){
data[i] = [temperature[len - i] , seconds[len - i]];
}
[len - i] indexes should be [len - i - 1], because the last item in the array is at an index equal to the length minus 1. Either that or change the loop initialisation and condition: for(var i=0; len=temperature.length-1; i<=len; i++).