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| author | Olivier Girondel <[email protected]> | 2015-01-04 04:40:55 +0100 |
|---|---|---|
| committer | Marcus Arendt <[email protected]> | 2015-01-14 15:58:51 +0100 |
| commit | fdf09e81de5e7f1ecfe71f98b56c411073badae8 (patch) | |
| tree | d6a46aeb887b2b829a01889ed364d943b7ed7536 /erts/emulator/beam | |
| parent | 821d84c5860a9a26185efa19be407796422e3090 (diff) | |
| download | otp-fdf09e81de5e7f1ecfe71f98b56c411073badae8.tar.gz otp-fdf09e81de5e7f1ecfe71f98b56c411073badae8.tar.bz2 otp-fdf09e81de5e7f1ecfe71f98b56c411073badae8.zip | |
Add math:log2/1
Diffstat (limited to 'erts/emulator/beam')
| -rw-r--r-- | erts/emulator/beam/bif.tab | 1 | ||||
| -rw-r--r-- | erts/emulator/beam/erl_math.c | 18 |
2 files changed, 19 insertions, 0 deletions
diff --git a/erts/emulator/beam/bif.tab b/erts/emulator/beam/bif.tab index aea3224342..1d0d214e77 100644 --- a/erts/emulator/beam/bif.tab +++ b/erts/emulator/beam/bif.tab @@ -194,6 +194,7 @@ bif math:erf/1 bif math:erfc/1 bif math:exp/1 bif math:log/1 +bif math:log2/1 bif math:log10/1 bif math:sqrt/1 bif math:atan2/2 diff --git a/erts/emulator/beam/erl_math.c b/erts/emulator/beam/erl_math.c index 16d4fdc09c..9b864628db 100644 --- a/erts/emulator/beam/erl_math.c +++ b/erts/emulator/beam/erl_math.c @@ -207,6 +207,24 @@ BIF_RETTYPE math_log_1(BIF_ALIST_1) return math_call_1(BIF_P, log, BIF_ARG_1); } +#ifdef HAVE_LOG2 +static double +log2_wrapper(double x) +{ + return log2(x); +} +#else +static double +log2_wrapper(double x) +{ + return log(x) / 0.6931471805599453; /* log(2.0); */ +} +#endif + +BIF_RETTYPE math_log2_1(BIF_ALIST_1) +{ + return math_call_1(BIF_P, log2_wrapper, BIF_ARG_1); +} BIF_RETTYPE math_log10_1(BIF_ALIST_1) { |