mirror of
https://github.com/luau-lang/luau.git
synced 2024-12-13 13:30:40 +00:00
73 lines
1.2 KiB
Lua
73 lines
1.2 KiB
Lua
|
--[[
|
||
|
The Great Computer Language Shootout
|
||
|
http://shootout.alioth.debian.org/
|
||
|
|
||
|
contributed by Ian Osgood
|
||
|
]]
|
||
|
local bench = script and require(script.Parent.bench_support) or require("bench_support")
|
||
|
|
||
|
function test()
|
||
|
|
||
|
function A(i,j)
|
||
|
return 1/((i+j)*(i+j+1)/2+i+1);
|
||
|
end
|
||
|
|
||
|
function Au(u,v)
|
||
|
for i = 0,#u-1 do
|
||
|
local t = 0;
|
||
|
for j = 0,#u-1 do
|
||
|
t = t + A(i,j) * u[j + 1];
|
||
|
end
|
||
|
v[i + 1] = t;
|
||
|
end
|
||
|
end
|
||
|
|
||
|
function Atu(u,v)
|
||
|
for i = 0,#u-1 do
|
||
|
local t = 0;
|
||
|
for j = 0,#u-1 do
|
||
|
t = t + A(j,i) * u[j + 1];
|
||
|
end
|
||
|
v[i + 1] = t;
|
||
|
end
|
||
|
end
|
||
|
|
||
|
function AtAu(u,v,w)
|
||
|
Au(u,w);
|
||
|
Atu(w,v);
|
||
|
end
|
||
|
|
||
|
function spectralnorm(n)
|
||
|
local u, v, w, vv, vBv = {}, {}, {}, 0, 0;
|
||
|
for i = 1,n do
|
||
|
u[i] = 1; v[i] = 0; w[i] = 0;
|
||
|
end
|
||
|
for i = 0,9 do
|
||
|
AtAu(u,v,w);
|
||
|
AtAu(v,u,w);
|
||
|
end
|
||
|
for i = 1,n do
|
||
|
vBv = vBv + u[i]*v[i];
|
||
|
vv = vv + v[i]*v[i];
|
||
|
end
|
||
|
return math.sqrt(vBv/vv);
|
||
|
end
|
||
|
|
||
|
local total = 0;
|
||
|
local i = 6
|
||
|
|
||
|
while i <= 48 do
|
||
|
total = total + spectralnorm(i);
|
||
|
i = i * 2
|
||
|
end
|
||
|
|
||
|
local expected = 5.086694231303284;
|
||
|
|
||
|
if (total ~= expected) then
|
||
|
assert(false, "ERROR: bad result: expected " .. expected .. " but got " .. total)
|
||
|
end
|
||
|
|
||
|
end
|
||
|
|
||
|
bench.runCode(test, "math-spectral-norm")
|