Question

I am recording acceleration data for the x-axis, so I have two values coming in – the x value, and the epoch time of the acceleration event. I want to store these as a hash, where the epoch time is the key and x-value is the value.

I created an array:

var arrX = new Array();

How can I add to it? Like this?

arrX[acceleration.timestamp] = acceleration.x

Answer 1

You should use an object, which can serve as a sort of “associative array” for this application. An object will provide support for the arbitrary, non-sequential keys that you mentioned, where an array would not.

var arrX = {};

arrX[acceleration.timestamp] = acceleration.x;

More information:

• Javascript Does Not Support Associative Arrays
• MDN: Arrays, par. 2