I have some data like
4 0.128 0.039
5 0.111 0.037
6 0.095 0.036
I need to get the second and third value by a known first value.
If I have a value of 4 I want to get back two variables: a = 0.111 and b = 0.037
What would be the best variable type for storing the data shown above to get simple access to the data? An object or an multidimensional array?
For ease of access, I'd go with an object containing arrays:
{
'4': [ 0.128, 0.039 ],
'5': [ 0.111, 0.037 ],
...
}
A second reason for the use of objects over arrays is ease of iteration. Imagine this:
var myData = [];
myData[4] = [ 0.128, 0.039 ];
myData[10] = [ 42, 23 ];
for (var i = 0; i < myData.length; i++)
{
console.log(myData[i]);
}
Would give you
null
null
null
null
[ 0.128, 0.039 ]
null
null
null
null
null
[ 42, 23 ]
... which is probably not what you want ;)
var x = 4, how do I access the values? data.x[0] and data.x[1]?
data[x][0], and so forth ;)What you would want to do is save it as a json object or just as an array as shown below:
Creating:
var obj = { "4":[0.128, 0.039], "5":[0.111, 0.037],"6":[0.095, 0.036] }
Retrieving:
obj.4 -> [0.128, 0.039] OR obj['4'] OR obj[0]
obj.5[0] -> 0.111 OR obj['5'][0] OR obj[1][0]
obj.5[1] -> 0.037 OR obj['5'][1] OR obj[1][1]
Cycling through retrieved obj:
for (var key in obj) {
alert(obj[key]);
}
I personally use arrays if the order of the elements is of importance, otherwise I use objects (objects are not good for preserving order).
In the end it comes down to what is the best tool for what is that you want to accomplish.
