kscience/kmath
9
0
Fork 1
Code Issues Pull Requests 6 Packages Projects Releases 16 Wiki Activity

Using kmath-stat for random normals

Browse Source
This commit is contained in:
Roland Grinis 2021-04-07 15:11:00 +01:00
parent 383376080e
commit 74dfca4e2e
1 changed files with 5 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/utils.kt
View File

@ -1,8 +1,8 @@
package space.kscience.kmath.tensors.core package space.kscience.kmath.tensors.core
import space.kscience.kmath.samplers.GaussianSampler
import space.kscience.kmath.stat.RandomGenerator
import space.kscience.kmath.structures.* import space.kscience.kmath.structures.*
import kotlin.random.Random
import kotlin.math.*
/** /**
* Returns a reference to [IntArray] containing all of the elements of this [Buffer]. * Returns a reference to [IntArray] containing all of the elements of this [Buffer].
@ -37,8 +37,9 @@ internal fun Buffer<Double>.array(): DoubleArray = when (this) {
} }
internal inline fun getRandomNormals(n: Int, seed: Long): DoubleArray { internal inline fun getRandomNormals(n: Int, seed: Long): DoubleArray {
val u = Random(seed) val distribution = GaussianSampler(0.0, 1.0)
return (0 until n).map { sqrt(-2.0 * ln(u.nextDouble())) * cos(2.0 * PI * u.nextDouble()) }.toDoubleArray() val generator = RandomGenerator.default(seed)
return distribution.sample(generator).nextBufferBlocking(n).toDoubleArray()
} }
internal inline fun minusIndexFrom(n: Int, i: Int) : Int = if (i >= 0) i else { internal inline fun minusIndexFrom(n: Int, i: Int) : Int = if (i >= 0) i else {