Add let block around call to partialsort! to avoid overhead from captured variable

[andreasnoack]

See #73 (comment) for some details. This isn't sufficient to make loess feasible for the dataset in #73 but it significantly speeds up the calculation. For a random subset with 10000 elements of the dataset from #73, I'm getting

julia> ft = @time loess(x, y);
  7.355545 seconds (357.20 M allocations: 5.519 GiB, 5.16% gc time)

with the current implementation and

julia> ft = @time loess(x, y);
  0.208809 seconds (10.97 k allocations: 200.746 MiB, 5.05% gc time)

with this PR.

Update: I've changed this to just use a let block instead the helper function. The performance impact is the same.

[codecov-commenter]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.09% 🎉

Comparison is base (1b34e35) 89.90% compared to head (ad4252f) 90.00%.

❗ Current head ad4252f differs from pull request most recent head c5b65ec. Consider uploading reports for the commit c5b65ec to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #76      +/-   ##
==========================================
+ Coverage   89.90%   90.00%   +0.09%     
==========================================
  Files           2        2              
  Lines         208      210       +2     
==========================================
+ Hits          187      189       +2     
  Misses         21       21              

Files Changed	Coverage Δ
src/kd.jl	96.19% <100.00%> (+0.07%)	⬆️

☔ View full report in Codecov by Sentry.
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[palday]

@andreasnoack if you merge in master, there is now a benchmarking CI

[github-actions]

Benchmark Report for /home/runner/work/Loess.jl/Loess.jl

Job Properties

• Time of benchmarks:
  • Target: 23 Aug 2023 - 19:45
  • Baseline: 23 Aug 2023 - 19:46
• Package commits:
  • Target: 24c703
  • Baseline: 5126a7
• Julia commits:
  • Target: e4ee48
  • Baseline: e4ee48
• Julia command flags:
  • Target: None
  • Baseline: -Cnative,-J/opt/hostedtoolcache/julia/1.9.2/x64/lib/julia/sys.so,-g1,-O3,-e,using Pkg; Pkg.update()
• Environment variables:
  • Target: None
  • Baseline: None

Results

A ratio greater than 1.0 denotes a possible regression (marked with ❌), while a ratio less
than 1.0 denotes a possible improvement (marked with ✅). Only significant results - results
that indicate possible regressions or improvements - are shown below (thus, an empty table means that all
benchmark results remained invariant between builds).

ID	time ratio	memory ratio
["random", "100"]	0.55 (5%) ✅	0.96 (1%) ✅
["random", "1000"]	0.46 (5%) ✅	0.70 (1%) ✅
["random", "10000"]	0.51 (5%) ✅	0.47 (1%) ✅
["random", "100000"]	0.53 (5%) ✅	0.43 (1%) ✅
["random", "1000000"]	0.57 (5%) ✅	0.40 (1%) ✅
["ties", "sine"]	0.06 (5%) ✅	0.05 (1%) ✅

Benchmark Group List

Here's a list of all the benchmark groups executed by this job:

• ["random"]
• ["ties"]

Julia versioninfo

Target

Julia Version 1.9.2
Commit e4ee485e909 (2023-07-05 09:39 UTC)
Platform Info:
  OS: Linux (x86_64-linux-gnu)
      Ubuntu 22.04.3 LTS
  uname: Linux 5.15.0-1041-azure #48-Ubuntu SMP Tue Jun 20 20:34:08 UTC 2023 x86_64 x86_64
  CPU: Intel(R) Xeon(R) Platinum 8272CL CPU @ 2.60GHz: 
              speed         user         nice          sys         idle          irq
       #1  2593 MHz        600 s          0 s        150 s       2084 s          0 s
       #2  2593 MHz       1068 s          0 s        136 s       1596 s          0 s
  Memory: 6.7694854736328125 GB (5423.71875 MB free)
  Uptime: 288.49 sec
  Load Avg:  1.0  0.62  0.28
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-14.0.6 (ORCJIT, skylake-avx512)
  Threads: 1 on 2 virtual cores

Baseline

Julia Version 1.9.2
Commit e4ee485e909 (2023-07-05 09:39 UTC)
Platform Info:
  OS: Linux (x86_64-linux-gnu)
      Ubuntu 22.04.3 LTS
  uname: Linux 5.15.0-1041-azure #48-Ubuntu SMP Tue Jun 20 20:34:08 UTC 2023 x86_64 x86_64
  CPU: Intel(R) Xeon(R) Platinum 8272CL CPU @ 2.60GHz: 
              speed         user         nice          sys         idle          irq
       #1  2593 MHz       1405 s          0 s        176 s       2133 s          0 s
       #2  2593 MHz       1168 s          0 s        162 s       2348 s          0 s
  Memory: 6.7694854736328125 GB (5422.44140625 MB free)
  Uptime: 376.65 sec
  Load Avg:  1.11  0.78  0.37
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-14.0.6 (ORCJIT, skylake-avx512)
  Threads: 1 on 2 virtual cores

[andreasnoack]

Superseded by #74