Port erlang calendar.day_to_year

[dkuku]

Erlang has much faster day_to_year implementation than elixir (3x faster according to benchee). The issue is that it only works for positive days.
This is a port that works for positive and negative days.

list = Enum.to_list(10_000_000..10_000_100)

Benchee.run(
  %{
    "elixir" => fn -> Enum.map(list, &Calendar.ISO.date_from_iso_days/1) end,
    "new_elixir" => fn -> Enum.map(list, &XCalendar.ISO.date_from_iso_days/1) end,
    "erlang" => fn -> Enum.map(list, &:calendar.gregorian_days_to_date/1) end
  },
  time: 5,
  memory_time: 5,
  profile_after: :fprof
)

Operating System: Linux
CPU Information: AMD Ryzen 7 7840HS with Radeon 780M Graphics
Number of Available Cores: 16
Available memory: 27.09 GB
Elixir 1.19.3
Erlang 28.1
JIT enabled: true

Benchmark suite executing with the following configuration:
warmup: 2 s
time: 5 s
memory time: 5 s
reduction time: 0 ns
parallel: 1
inputs: none specified
Estimated total run time: 36 s
Excluding outliers: false

Benchmarking elixir ...
Benchmarking erlang ...
Benchmarking new_elixir ...
Calculating statistics...
Formatting results...

Name                 ips        average  deviation         median         99th %
erlang          178.43 K        5.60 μs   ±151.11%        5.31 μs        9.43 μs
new_elixir      177.48 K        5.63 μs   ±142.16%        5.38 μs        9.30 μs
elixir           57.63 K       17.35 μs    ±45.38%       17.02 μs       23.09 μs

Comparison:
erlang          178.43 K
new_elixir      177.48 K - 1.01x slower +0.0301 μs
elixir           57.63 K - 3.10x slower +11.75 μs

Memory usage statistics:

Name          Memory usage
erlang            14.20 KB
new_elixir        11.84 KB - 0.83x memory usage -2.36719 KB
elixir            11.84 KB - 0.83x memory usage -2.36719 KB

**All measurements for memory usage were the same**

Profiling erlang with fprof...
Reading trace data...
..
End of trace!
Processing data...
Creating output...
Done!

                                                                   CNT    ACC (ms)    OWN (ms)
Total                                                             1408       2.574       2.574
:fprof.apply_start_stop/4                                            0       2.574       0.008
anonymous fn/2 in Benchee.Profile.run/4                              1       2.566       0.003
Benchee.Benchmark.Runner.run_once/2                                  1       2.447       0.004
Benchee.Benchmark.Runner.collect_return_value/2                      1       2.438       0.005
anonymous fn/1 in :elixir_compiler_2.__FILE__/1                      1       2.427       0.001
Enum.map/2                                                           1       2.426       0.001
Enum."-map/2-lists^map/1-1-"/2                                     102       2.425       0.304
:calendar.gregorian_days_to_date/1                                 101       2.121       0.303
:calendar.day_to_year/1                                            101       1.212       0.404
:calendar.year_day_to_date/2                                       101       0.606       0.303
:calendar.dty/5                                                    101       0.606       0.303
:calendar.is_leap_year/1                                           202       0.404       0.202
:calendar.dy/1                                                     303       0.303       0.303
:calendar.is_leap_year1/1                                          202       0.202       0.202
Benchee.Benchmark.BenchmarkConfig.from/1                             1       0.116       0.004
:calendar.year_day_to_date2/2                                      101       0.101       0.101
Kernel.struct!/2                                                     1       0.093       0.003
Benchee.Benchmark.BenchmarkConfig.__struct__/1                       1       0.089       0.001
Enum.reduce/3                                                        1       0.088       0.001
:maps.fold/3                                                         1       0.087       0.003
:maps.fold_1/4                                                      14       0.079       0.040
anonymous fn/4 in Enum.reduce/3                                     13       0.026       0.013
Map.take/2                                                           1       0.019       0.001
Map.take/3                                                          14       0.018       0.015
:maps.try_next/2                                                    13       0.013       0.013
anonymous fn/2 in Benchee.Benchmark.BenchmarkConfig.__struct        13       0.013       0.013
Benchee.Benchmark.Hooks.run_before_scenario/2                        1       0.004       0.002
Benchee.Benchmark.Hooks.run_before_function/2                        4       0.004       0.004
Benchee.Benchmark.Hooks.run_before_each/2                            1       0.004       0.002
:maps.next/1                                                         1       0.003       0.002
:maps.from_list/1                                                    1       0.003       0.003
:maps.iterator/1                                                     1       0.002       0.001
:maps.iterator/2                                                     1       0.001       0.001
:erts_internal.map_next/3                                            1       0.001       0.001
Kernel.validate_struct!/3                                            1       0.001       0.001
Benchee.Benchmark.Runner.main_function/2                             1       0.001       0.001
Benchee.Benchmark.Hooks.run_after_scenario/2                         1       0.001       0.001
Benchee.Benchmark.Hooks.run_after_each/3                             1       0.001       0.001
:undefined                                                           0       0.000       0.000
:suspend                                                             1       0.000       0.000

Profiling new_elixir with fprof...
Reading trace data...
..
End of trace!
Processing data...
Creating output...
Done!

                                                                   CNT    ACC (ms)    OWN (ms)
Total                                                             1409       2.775       2.774
:fprof.apply_start_stop/4                                            0       2.775       0.008
anonymous fn/2 in Benchee.Profile.run/4                              1       2.767       0.003
Benchee.Benchmark.Runner.run_once/2                                  1       2.651       0.004
Benchee.Benchmark.Runner.collect_return_value/2                      1       2.642       0.005
anonymous fn/1 in :elixir_compiler_2.__FILE__/1                      1       2.631       0.001
Enum.map/2                                                           1       2.630       0.001
Enum."-map/2-lists^map/1-1-"/2                                     102       2.629       0.305
XCalendar.ISO.date_from_iso_days/1                                 101       2.323       0.404
XCalendar.ISO.days_to_year/1                                       101       1.717       0.606
XCalendar.ISO.days_to_year_interpolated/5                          101       0.707       0.404
XCalendar.ISO.floor_div_positive_divisor/2                         303       0.303       0.303
XCalendar.ISO.days_in_previous_years/1                             303       0.303       0.303
XCalendar.ISO.leap_year?/1                                         202       0.202       0.202
Benchee.Benchmark.BenchmarkConfig.from/1                             1       0.113       0.003
XCalendar.ISO.year_day_to_year_date/1                              101       0.101       0.101
Kernel.struct!/2                                                     1       0.093       0.002
Benchee.Benchmark.BenchmarkConfig.__struct__/1                       1       0.090       0.001
Enum.reduce/3                                                        1       0.089       0.001
:maps.fold/3                                                         1       0.088       0.004
:maps.fold_1/4                                                      14       0.079       0.040
anonymous fn/4 in Enum.reduce/3                                     13       0.026       0.013
Map.take/2                                                           1       0.017       0.001
Map.take/3                                                          14       0.016       0.015
:maps.try_next/2                                                    13       0.013       0.013
anonymous fn/2 in Benchee.Benchmark.BenchmarkConfig.__struct        13       0.013       0.013
Benchee.Benchmark.Hooks.run_before_scenario/2                        1       0.004       0.002
Benchee.Benchmark.Hooks.run_before_function/2                        4       0.004       0.004
Benchee.Benchmark.Hooks.run_before_each/2                            1       0.004       0.002
:maps.next/1                                                         1       0.003       0.002
:maps.iterator/1                                                     1       0.002       0.001
:maps.iterator/2                                                     1       0.001       0.001
:maps.from_list/1                                                    1       0.001       0.001
:erts_internal.map_next/3                                            1       0.001       0.001
Kernel.validate_struct!/3                                            1       0.001       0.001
Benchee.Benchmark.Runner.main_function/2                             1       0.001       0.001
Benchee.Benchmark.Hooks.run_after_scenario/2                         1       0.001       0.001
Benchee.Benchmark.Hooks.run_after_each/3                             1       0.001       0.001
:suspend                                                             2       0.001       0.000
:undefined                                                           0       0.000       0.000

Profiling elixir with fprof...
Reading trace data...
.......
End of trace!
Processing data...
Creating output...
Done!

                                                                   CNT    ACC (ms)    OWN (ms)
Total                                                             4440       7.025       7.023
:fprof.apply_start_stop/4                                            0       7.025       0.008
anonymous fn/2 in Benchee.Profile.run/4                              1       7.017       0.003
Benchee.Benchmark.Runner.run_once/2                                  1       6.895       0.004
Benchee.Benchmark.Runner.collect_return_value/2                      1       6.886       0.005
anonymous fn/1 in :elixir_compiler_2.__FILE__/1                      1       6.875       0.001
Enum.map/2                                                           1       6.874       0.001
Enum."-map/2-lists^map/1-1-"/2                                     102       6.873       0.304
Calendar.ISO.date_from_iso_days/1                                  101       6.569       0.404
Calendar.ISO.days_to_year/1                                        101       5.963       0.303
Calendar.ISO.days_to_year/3                                       1919       5.559       3.739
Calendar.ISO.days_in_previous_years/1                             1919       1.919       1.919
Benchee.Benchmark.BenchmarkConfig.from/1                             1       0.119       0.003
Calendar.ISO.year_day_to_year_date/2                               101       0.101       0.101
Calendar.ISO.leap_year?/1                                          101       0.101       0.101
Kernel.struct!/2                                                     1       0.097       0.003
Benchee.Benchmark.BenchmarkConfig.__struct__/1                       1       0.093       0.001
Enum.reduce/3                                                        1       0.092       0.001
:maps.fold/3                                                         1       0.091       0.004
:maps.fold_1/4                                                      14       0.082       0.040
anonymous fn/4 in Enum.reduce/3                                     13       0.029       0.013
Map.take/2                                                           1       0.019       0.002
Map.take/3                                                          14       0.017       0.016
anonymous fn/2 in Benchee.Benchmark.BenchmarkConfig.__struct        13       0.016       0.016
:maps.try_next/2                                                    13       0.013       0.013
Benchee.Benchmark.Hooks.run_before_scenario/2                        1       0.004       0.002
Benchee.Benchmark.Hooks.run_before_function/2                        4       0.004       0.004
Benchee.Benchmark.Hooks.run_before_each/2                            1       0.004       0.002
:maps.next/1                                                         1       0.003       0.002
:maps.iterator/1                                                     1       0.002       0.001
:suspend                                                             3       0.002       0.000
:maps.iterator/2                                                     1       0.001       0.001
:maps.from_list/1                                                    1       0.001       0.001
:erts_internal.map_next/3                                            1       0.001       0.001
Kernel.validate_struct!/3                                            1       0.001       0.001
Benchee.Benchmark.Runner.main_function/2                             1       0.001       0.001
Benchee.Benchmark.Hooks.run_after_scenario/2                         1       0.001       0.001
Benchee.Benchmark.Hooks.run_after_each/3                             1       0.001       0.001
:undefined                                                           0       0.000       0.000

[josevalim]

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