mandel.jl

function mandel(z)
    c = z
    maxiter = 80
    for n = 1:maxiter
        if abs(z) > 2
            return n-1
        end
        z = z^2 + c
    end
    return maxiter
end

mandel.py

def mandel(z):
    maxiter = 80
    c = z
    for n in range(maxiter):
        if abs(z) > 2:
            return n
        z = z*z + c
    return maxiter

randmatstat.f90

integer, intent(in) :: t
real(dp), intent(out) :: s1, s2
real(dp), allocatable, dimension(:, :) :: a, b, c, d, P, Q, X
real(dp), allocatable :: v(:), w(:)
integer :: n, i
n = 5
allocate(a(n, n), b(n, n), c(n, n), d(n, n))
allocate(P(4*n, n), Q(2*n, 2*n), X(2*n, 2*n))
allocate(v(t), w(t))
do i = 1, t
    call randn(a)
    call randn(b)
    call randn(c)
    call randn(d)
    P(:n, :)=a; P(n+1:2*n, :)=b; P(2*n+1:3*n, :)=c; P(3*n+1:, :)=d
    Q(:n,    :n) = a; Q(n+1:,    :n) = b
    Q(:n, n+1: ) = c; Q(n+1:, n+1: ) = d
    X = matmul(transpose(P), P)
    X = matmul(X, X)
    X = matmul(X, X)
    v(i) = trace(X)
    X = matmul(transpose(Q), Q)
    X = matmul(X, X)
    X = matmul(X, X)
    w(i) = trace(X)
end do
s1 = std(v) / mean(v)
s2 = std(w) / mean(w)
end subroutine

randmatstat.py

def randmatstat(t):
    n = 5
    v = zeros(t)
    w = zeros(t)
    for i in range(1,t):
        a = numpy.random.randn(n, n)
        b = numpy.random.randn(n, n)
        c = numpy.random.randn(n, n)
        d = numpy.random.randn(n, n)
        P = matrix(hstack((a, b, c, d)))
        Q = matrix(vstack((hstack((a, b)), hstack((c, d)))))
        v[i] = trace(matrix_power(transpose(P)*P, 4))
        w[i] = trace(matrix_power(transpose(Q)*Q, 4))
    return (std(v)/mean(v), std(w)/mean(w))

summarize.jl

r = rand(10000000)

summarize(r) = mean(r), maximum(r), minimum(r)

function summarize_loop(r)
	maxval = realmin(eltype(r))
   	minval = realmax(eltype(r))
   	s = zero(eltype(r))
   	for i = 1:length(r)
   		d = r[i]
   		s+=d
   		if d > maxval
   			maxval = d
   		elseif d < minval
   			minval = d
   		end
   	end
   	s/length(r), maxval, minval
end


function summarize_loop2(r)
	maxval = realmin(eltype(r))
   	minval = realmax(eltype(r))
   	s = 0
   	for i = 1:length(r)
   		d = r[i]
   		s+=d
   		if d > maxval
   			maxval = d
   		elseif d < minval
   			minval = d
   		end
   	end
   	s/length(r), maxval, minval
end

@time for i=1:10 summarize(r) end
@time for i=1:10 summarize_loop(r) end
@time summarize_loop(r)

summarize.py

import numpy, time

r = numpy.random.rand(10000000)

def summarize(r):
	return r.mean(), numpy.amax(r), numpy.amin(r)

def summarize_loop(r):
	maxval = -numpy.inf
   	minval = numpy.info
   	s = 0.0
   	for i in range(len(r)):
   		d = r[i]
   		s+=d
   		if d > maxval:
   			maxval = d
   		elif d < minval:
   			minval = d
   	return s/length(r), maxval, minval

tstart = time.time()
meanval, maxval, minval = summarize_loop(r)
tend=time.time()
print(10*(tend-tstart))

tstart = time.time()
for i in range(10):
	meanval, maxval, minval = summarize(r)
tend=time.time()
print(tend-tstart)