kmath/kmath-nd4j/README.md

ND4J NDStructure implementation (kmath-nd4j)

This subproject implements the following features:

• NDStructure wrapper for INDArray.
• Optimized NDRing implementations for INDArray storing Ints and Longs.
• Optimized NDField implementations for INDArray storing Floats and Doubles.

Artifact:

This module is distributed in the artifact scientifik:kmath-nd4j:0.1.4-dev-8.

Gradle:

repositories {
    mavenCentral()
    maven { url 'https://dl.bintray.com/mipt-npm/scientifik' }
    maven { url 'https://dl.bintray.com/mipt-npm/dev' }
}

dependencies {
    implementation 'scientifik:kmath-nd4j:0.1.4-dev-8'
    implementation 'org.nd4j:nd4j-native-platform:1.0.0-beta7'
}

Gradle Kotlin DSL:

repositories {
    mavenCentral()
    maven("https://dl.bintray.com/mipt-npm/scientifik")
    maven("https://dl.bintray.com/mipt-npm/dev")
}

dependencies {
    implementation("scientifik:kmath-nd4j:0.1.4-dev-8")
    implementation("org.nd4j:nd4j-native-platform:1.0.0-beta7")
}

This distribution also needs an implementation of ND4J API. The ND4J Native Platform is usually the fastest one, so it is included to the snippet.

Examples

NDStructure wrapper for INDArray:

import org.nd4j.linalg.factory.*
import scientifik.kmath.nd4j.*
import scientifik.kmath.structures.*

val array = Nd4j.ones(2, 2).asRealStructure()
println(array[0, 0]) // 1.0
array[intArrayOf(0, 0)] = 24.0
println(array[0, 0]) // 24.0

Fast element-wise and in-place arithmetics for INDArray:

import org.nd4j.linalg.factory.*
import scientifik.kmath.nd4j.*
import scientifik.kmath.operations.*

val field = RealINDArrayField(intArrayOf(2, 2))
val array = Nd4j.rand(2, 2).asRealStructure()

val res = field {
    (25.0 / array + 20) * 4
}

println(res.ndArray)
// [[  250.6449,  428.5840], 
//  [  269.7913,  202.2077]]

Contributed by Iaroslav Postovalov.