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September 2017 Update

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This commit is contained in:
Ingy döt Net 2017-09-23 10:01:46 +02:00
parent bba7bfd280
commit ba8067c3b7
14570 changed files with 153136 additions and 63871 deletions
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26
Task/Monte-Carlo-methods/Futhark/monte-carlo-methods.futhark
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@ -1,6 +1,8 @@
import "futlib/math"
default(f32)
fun dirvcts(): [2][30]int =
fun dirvcts(): [2][30]i32 =
[
[
536870912, 268435456, 134217728, 67108864, 33554432, 16777216, 8388608, 4194304, 2097152, 1048576, 524288, 262144, 131072, 65536, 32768, 16384, 8192, 4096, 2048, 1024, 512, 256, 128, 64, 32, 16, 8, 4, 2, 1
@ -11,36 +13,36 @@ fun dirvcts(): [2][30]int =
]
fun grayCode(x: int): int = (x >> 1) ^ x
fun grayCode(x: i32): i32 = (x >> 1) ^ x
----------------------------------------
--- Sobol Generator
----------------------------------------
fun testBit(n: int, ind: int): bool =
fun testBit(n: i32, ind: i32): bool =
let t = (1 << ind) in (n & t) == t
fun xorInds(n: int) (dir_vs: [num_bits]int): int =
let reldv_vals = zipWith (fn dv i =>
fun xorInds(n: i32) (dir_vs: [num_bits]i32): i32 =
let reldv_vals = zipWith (\ dv i ->
if testBit(grayCode n,i)
then dv else 0)
dir_vs (iota num_bits)
in reduce (^) 0 reldv_vals
fun sobolIndI (dir_vs: [m][num_bits]int, n: int): [m]int =
fun sobolIndI (dir_vs: [m][num_bits]i32, n: i32): [m]i32 =
map (xorInds n) dir_vs
fun sobolIndR(dir_vs: [m][num_bits]int) (n: int ): [m]f32 =
fun sobolIndR(dir_vs: [m][num_bits]i32) (n: i32 ): [m]f32 =
let divisor = 2.0 ** f32(num_bits)
let arri = sobolIndI( dir_vs, n )
in map (fn (x: int): f32 => f32(x) / divisor) arri
in map (\ (x: i32): f32 -> f32(x) / divisor) arri
fun main(n: int): f32 =
fun main(n: i32): f32 =
let rand_nums = map (sobolIndR (dirvcts())) (iota n)
let dists = map (fn xy =>
let (x,y) = (xy[0],xy[1]) in sqrt32(x*x + y*y))
let dists = map (\xy ->
let (x,y) = (xy[0],xy[1]) in f32.sqrt(x*x + y*y))
rand_nums
let bs = map (fn d => if d <= 1.0f32 then 1 else 0) dists
let bs = map (\d -> if d <= 1.0f32 then 1 else 0) dists
let inside = reduce (+) 0 bs
in 4.0f32*f32(inside)/f32(n)