Wow, we were using long doubles before. I don't think we need that much
precision for cave survey. In catch there is Approx() that should take care
of floating point comparison correctly.
On Fri, Mar 9, 2018 at 11:30 AM Wookey <woo...@wookware.org> wrote:
> A bit of research tells that using 'long double' causes 80-bit fp on x86
> (i386 and amd64), as opposed to the 64-bit IEE 754 fp representation used
> on other platforms, which is what you get if you specify double.
>
> So I tried changing the angle.{cpp.h} code to use double instead of long
> double.
>
> That doesn't fix the problrematic tests, but does cause another 43 to fail:
> test cases: 8 | 3 passed | 5 failed
> assertions: 202 | 155 passed | 47 failed
>
> They all fail equality tests, despite them clearly being 'equal
> enough' for our purposes.
>
> e.g.
> /home/wookey/dewalls-1.0.0+ds1/test/azimuthparsingtests.cpp:31: FAILED:
> CHECK( WallsSurveyParser("5:4").azimuth(Angle::Degrees) == UAngle(5 + 4
> / 60.0, Angle::Degrees) )
> with expansion:
> 5.06667 deg == 5.06667 deg
>
> I see that 'approx' is used in the codebase which you might hope would
> get all this right, but clearly excessive precision is being used for
> our purposes (cave survey data).
>
> I'm not sure how to fix this.
>
> I've done an upload in the meantime with the previous bodge of the
> tests, and to fix another bug too and let the package migrate to
> testing. But getting the codebase to do what we actually expect would
> be good.
>
> This is the patch I used to try double for angles:
>
> Author: Wookey <woo...@debian.org>
> Last-Update: 2018-03-09
>
> --- dewalls-1.0.0+ds1.orig/src/angle.cpp
> +++ dewalls-1.0.0+ds1/src/angle.cpp
> @@ -3,13 +3,13 @@
>
> namespace dewalls {
>
> -const long double PI = acosl(-1.0L);
> -const long double DegreesToRadians = PI / 180.0L;
> -const long double GradiansToRadians = PI / 200.0L;
> -const long double MilsNATOToRadians = PI / 3200.0L;
> -const long double RadiansToDegrees = 180.0L / PI;
> -const long double RadiansToGradians = 200.0L / PI;
> -const long double RadiansToMilsNATO = 3200.0L / PI;
> +const double PI = acosl(-1.0L);
> +const double DegreesToRadians = PI / 180.0L;
> +const double GradiansToRadians = PI / 200.0L;
> +const double MilsNATOToRadians = PI / 3200.0L;
> +const double RadiansToDegrees = 180.0L / PI;
> +const double RadiansToGradians = 200.0L / PI;
> +const double RadiansToMilsNATO = 3200.0L / PI;
>
> QString Angle::Name("angle");
>
> @@ -30,7 +30,7 @@ QString Angle::symbolFor(Unit unit) {
> }
> }
>
> -long double Angle::toBase(long double quantity, Unit fromUnit) {
> +double Angle::toBase(double quantity, Unit fromUnit) {
> switch (fromUnit) {
> case Radians:
> return quantity;
> @@ -47,7 +47,7 @@ long double Angle::toBase(long double qu
> }
> }
>
> -long double Angle::fromBase(long double quantity, Unit toUnit) {
> +double Angle::fromBase(double quantity, Unit toUnit) {
> switch (toUnit) {
> case Radians:
> return quantity;
> @@ -64,7 +64,7 @@ long double Angle::fromBase(long double
> }
> }
>
> -long double Angle::convert(long double quantity, Unit fromUnit, Unit
> toUnit) {
> +double Angle::convert(double quantity, Unit fromUnit, Unit toUnit) {
> return fromBase(toBase(quantity, fromUnit), toUnit);
> }
>
> --- dewalls-1.0.0+ds1.orig/src/angle.h
> +++ dewalls-1.0.0+ds1/src/angle.h
> @@ -21,9 +21,9 @@ public:
>
> static QString Name;
>
> - static long double toBase(long double quantity, Unit fromUnit);
> - static long double fromBase(long double quantity, Unit toUnit);
> - static long double convert(long double quantity, Unit fromUnit, Unit
> toUnit);
> + static double toBase(double quantity, Unit fromUnit);
> + static double fromBase(double quantity, Unit toUnit);
> + static double convert(double quantity, Unit fromUnit, Unit toUnit);
> static QString symbolFor(Unit unit);
> };
>
>
>
> Wookey
> --
> Principal hats: Linaro, Debian, Wookware, ARM
> http://wookware.org/
>
--
Phi|ip
