How do I use this, if I want to put in less data

Say I have data like this

```
var get_random_data = function()
{
var data = [];

var getRandomInt = function(min, max)
{
return Math.floor(Math.random() * (max - min + 1)) + min;
}

for(var i = 0; i < 10000; i++)
{
data.push({
id: i,
date_wide: new Date(2012, getRandomInt(5,9), getRandomInt(1,30), getRandomInt(0,23)),
a: getRandomInt(0,4999)
});
}

return data;
}

```

So there is a date and a histogram off that date (two graphs). How would I set the relations for this? (So that you can scroll through the date and see the histogram).

I've tried many things but I get stuck at undescriptive d3 errors.