On 08/21/2014 11:53 AM, nrgyzer wrote:
> double d = 1.23456789;
> JSONValue j = d;
> sendToRemote(toJSON(&j));
> }
>
> My problem is that the remote PC receives 1.23457 instead of
> 1.23456789.
I think it is due to the following code simply calling to!string in
std/phobos/json.d:
case JSON_TYPE.FLOAT:
json.put(to!string(value.store.floating));
break;
> But when I add the following:
>
> import std.json;
> import std.stdio;
> void main()
> {
> double d = 1.23456789;
> JSONValue j = d;
> sendToRemote(toJSON(&j));
> writefln("%.8f", j.floating);
> }
>
> writefln() shows me 1.23456789. So, the value is correct.
It is more precise but still not correct because that specific double
value cannot be represented exactly.
> Is there any chance I can send 1.23456789
> instead of 1.23457 to my remote PC?
You can call a function like the following:
import std.string;
import std.json;
import std.stdio;
string morePrecisely(double d)
{
return format("%.20g", d);
}
void main()
{
double d = 1.23456789;
JSONValue root = [ "value" : d.morePrecisely ];
writeln(toJSON(&root));
}
Of course do something more sensible than hard-coding the 20 in that
format string. :)
> Note: I cannot use strings because the other PC expects a numeric
> data type.
I don't think it is a concern as JSON does not encode types. It is up to
the receiver how to interpret the data. Here is the output of the
program above:
{"value":"1.2345678899999998901"}
Ali
