Re: How to serialize a double.
On Thursday, 1 December 2016 at 07:13:45 UTC, Bauss wrote:
On Thursday, 1 December 2016 at 00:36:30 UTC, Jake Pittis wrote:
[...]
You could do something like below which will allow you to
serialize any number.
import std.stdio : writeln;
import std.traits : isNumeric;
ubyte[] bytes(T)(T num) if (isNumeric!T) {
auto buf = new ubyte[T.sizeof];
(*cast(T*)(buf.ptr)) = num;
return buf;
}
T value(T)(ubyte[] buf) if (isNumeric!T) {
return (*cast(T*)(buf.ptr));
}
And example usage:
double foo = 3.14;
writeln(foo); // Prints 3.14
ubyte[] bar = foo.bytes;
writeln(bar); // Prints the bytes equal to 3.14
foo = bar.value!double;
writeln(foo); // Prints 3.14
Regarding the test assertion that failed. Turns out I had a bug
in the test. (of course)
This last solution is very pretty. Thanks.
You folks are all so kind!
Re: How to serialize a double.
On Thursday, 1 December 2016 at 00:36:30 UTC, Jake Pittis wrote:
How do I convert a double to a ubyte[]?
I've tried all sorts of things including converting the double
to a ulong and trying to serialize the ulong. For example test
bellow fails.
unittest {
double d = 3.14;
ulong l = *cast(ulong*)(&d);
double after = *cast(double*)(&l));
assert(after == d); // This fails.
}
You could do something like below which will allow you to
serialize any number.
import std.stdio : writeln;
import std.traits : isNumeric;
ubyte[] bytes(T)(T num) if (isNumeric!T) {
auto buf = new ubyte[T.sizeof];
(*cast(T*)(buf.ptr)) = num;
return buf;
}
T value(T)(ubyte[] buf) if (isNumeric!T) {
return (*cast(T*)(buf.ptr));
}
And example usage:
double foo = 3.14;
writeln(foo); // Prints 3.14
ubyte[] bar = foo.bytes;
writeln(bar); // Prints the bytes equal to 3.14
foo = bar.value!double;
writeln(foo); // Prints 3.14
Re: How to serialize a double.
On Thursday, 1 December 2016 at 00:36:30 UTC, Jake Pittis wrote:
How do I convert a double to a ubyte[]?
I've tried all sorts of things including converting the double
to a ulong and trying to serialize the ulong. For example test
bellow fails.
unittest {
double d = 3.14;
ulong l = *cast(ulong*)(&d);
double after = *cast(double*)(&l));
assert(after == d); // This fails.
}
platform, archi, compiler version ?
Re: How to serialize a double.
On Thu, Dec 01, 2016 at 12:36:30AM +, Jake Pittis via Digitalmars-d-learn
wrote:
> How do I convert a double to a ubyte[]?
>
> I've tried all sorts of things including converting the double to a
> ulong and trying to serialize the ulong. For example test bellow
> fails.
>
>
> unittest {
> double d = 3.14;
> ulong l = *cast(ulong*)(&d);
> double after = *cast(double*)(&l));
> assert(after == d); // This fails.
> }
>
union U
{
ubyte[double.sizeof] bytes;
double d;
}
U u, v;
u.d = 3.14159;
v.bytes[] = u.bytes[];
assert(v.d == 3.14159);
T
--
Those who don't understand Unix are condemned to reinvent it, poorly.
Re: How to serialize a double.
On Thursday, 1 December 2016 at 00:36:30 UTC, Jake Pittis wrote:
How do I convert a double to a ubyte[]?
I've tried all sorts of things including converting the double
to a ulong and trying to serialize the ulong. For example test
bellow fails.
unittest {
double d = 3.14;
ulong l = *cast(ulong*)(&d);
double after = *cast(double*)(&l));
assert(after == d); // This fails.
}
That test passes for me, are you sure there isn't something else
wrong with your code? Check to see if it works for just a ulong
that has values in it's upper 32-bits?
How to serialize a double.
How do I convert a double to a ubyte[]?
I've tried all sorts of things including converting the double to
a ulong and trying to serialize the ulong. For example test
bellow fails.
unittest {
double d = 3.14;
ulong l = *cast(ulong*)(&d);
double after = *cast(double*)(&l));
assert(after == d); // This fails.
}
