Jeffrey Sarnoff JeffreySarnoff

re: https://twitter.com/SimonDeDeo/status/1344031423704006656

You are not timing the same thing in each language. See below for what you were timing in Julia.
And, as has been mentioned, use @time or @btime from BenchmarkTools.jl (time does not do what you expect it to do). When using @time, run the timing once to precompile the test before considering the results valid. The first run may take considerably longer, and that extra time is not computing time. I have omitted those lines below.

	struct ZERO end
	const Zero = ZERO()

	# to display Zero as Zero
	const ShowZero = :Zero
	# to display Zero as 0
	# const ShowZero = 0
	Base.show(io::IO, x::ZERO) = print(io, ShowZero)

	Base.zero(::ZERO) = 0

	# very small subset of data, for testing

	N = 5 # people
	T = 3 # times

	data = Float32.([
	# x y z
	1.75 0.0 0.75 # person 1 time 1
	2.75 1.75 0.75 # person 1 time 2
	1.25 2.75 -0.75 # person 1 time 3

	# see example at line 80

	using StatsBase

	function StatsBase.median(a::T, b::T, c::T) where {T}
	b, c = minmax(b, c)
	a, c = minmax(a, c)
	max(a, b)
	end

	# see example at line 70
	# see accumulator enhancement at line 70

	using StatsBase

	abstract type Accumulator{T} <: Function end

	const AccNum = Float64 # client settable via ENV

	StatsBase.nobs(acc::Accumulator) = acc.nobs

	# see example at line 60

	using StatsBase

	abstract type Accumulator{T} <: Function end

	const AccNum = Float64 # client settable via ENV

	StatsBase.nobs(acc::Accumulator) = acc.nobs

	function shiftup(v::AbstractVector{T}, start, finish) where {T}
	for i in finish:-1:start
	@inbounds v[i+1] = v[i]
	end
	end

	function shiftup4(v::AbstractVector{T}, start, finish) where {T}
	n = finish - start
	q, r = fldmod(n, 4)
	@inbounds for i in finish-3:-4:start+r

	#=
	* Data for log.
	*
	* Copyright (c) 2018, Arm Limited.
	* SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
	=#

	const OneAsUInt64 = 0x3ff0000000000000

	const LOG_TABLE_BITS = 7

	using BenchmarkTools
	const BT=BenchmarkTools.DEFAULT_PARAMETERS;
	BT.samples=60_000; BT.time_tolerance=1/8192;
	#=
	IS{Int64} == Union{Int64, Symbol}
	IS{Int32} == Union{Int32, Symbol}
	=#
	const IS = Union{I,Symbol} where {I<:Integer}

	# test vars, length(chrs) == 96

	# provide context when a NaN is generated
	# IMPORTANT!! define these before overloading the arithmetic functions

	function nanfound(fncall)
	stk = stacktrace() # stacktrace(catch_backtrace())
	stk = relevantframes(stk)
	info = []
	for frame in stk
	push!(info, frameinfo(frame))
	end