json_decode is rounding floats, how can I prevent it?

Question

I have a rather big json file with coordinates in the following format

"[[3.2,1],[4.8,2]]"

which represents (3.2,1) and (4.8,2)

I'm using these coördinates to generate a D3 geographic map, but when php is modelling this information into a geoJSONobject I encounter the following error:

I need to transform the coordinates into a array for which I use json_decode. However:

json_decode("[[3.2,1],[4.8,2]]")

returns

Array
(
[0] => Array
    (
        [0] => 3
        [1] => 1
    )
[1] => Array
    (
        [0] => 4
        [1] => 2
    )
)

Where I lose the decimals. How can I prevent this?

Edit:

{"type": "FeatureCollection",
 "features": [{
        "type": "Feature",
        "geometry": {
            "type": "Polygon",
            "coordinates": "[[[8.7, 11], [8.89, 12.13],[9.27, 12.13], [9.9, 12], [9.7, 10.8], [8.7, 11]]]"
        },
        "properties": {
            "name": "04",
            "count": "25"
        }
    }]
}

This is an example of the data I'm getting as output. (It is supposed to represent a map of rooms which are get a density color by its usage)

I am able to parse this using jQuery.parseJSON(data), but running the following D3 code generates the weirdest errors:

val(svgname).append("g")
    .selectAll("path")
    .data(geoJSONobject.features)
    .enter().append("path")
    .attr("d", path)
    ...

I think it's because of the quotes around the array of coordinates.

Edit (2) - actual solution

The solution I accepted was a workaround, but the true issue was localized php-settings. using:

echo json_encode($dataset, JSON_NUMERIC_CHECK);

in the php-file, all the issues were resolved. Though I'd update the question since it is still being looked at (if anyone would encouter the issue)

Answer 1

I had the same problem. I solved it using the followin regex

SOLUTION 1

$yourJsonVariable = preg_replace('/:\s*(\-?\d+(\.\d+)?([e|E][\-|\+]\d+)?)/', ': "$1"', $yourJsonVariable);

Convert it into array

$array = json_decode($yourJsonVariable, true);

Credits goes to this SO LINK

SOLUTION 2

You can set ini_set('precision',1);

SOLUTION 3

$decoded = json_decode($encoded, true, null, JSON_BIGINT_AS_STRING);

NOTE: The Last solution will work only for PHP > 5.4

You might want to take a look at this Blog