kmath-ast

Extensions to MST API: transformations, dynamic compilation and visualization.

src/commonMain/kotlin/space/kscience/kmath/ast/parser.kt : Expression language and its parser
src/jvmMain/kotlin/space/kscience/kmath/asm/asm.kt : Dynamic MST to JVM bytecode compiler
src/jsMain/kotlin/space/kscience/kmath/estree/estree.kt : Dynamic MST to JS compiler
src/commonMain/kotlin/space/kscience/kmath/ast/rendering/MathRenderer.kt : Extendable MST rendering

Artifact:

The Maven coordinates of this project are space.kscience:kmath-ast:0.3.0.

Gradle Groovy:

repositories {
    maven { url 'https://repo.kotlin.link' }
    mavenCentral()
}

dependencies {
    implementation 'space.kscience:kmath-ast:0.3.0'
}

Gradle Kotlin DSL:

repositories {
    maven("https://repo.kotlin.link")
    mavenCentral()
}

dependencies {
    implementation("space.kscience:kmath-ast:0.3.0")
}

Parsing expressions

In this module there is a parser from human-readable strings like "x^3-x+3" (in the more specific reference/ArithmeticsEvaluator.g4) to MST instances.

Supported literals:

Constants and variables (consist of latin letters, digits and underscores, can't start with digit): x, _Abc2.
Numbers: 123, 1.02, 1e10, 1e-10, 1.0e+3—all parsed either as kotlin.Long or kotlin.Double.

Supported binary operators (from the highest precedence to the lowest one):

^
*, /
+, -

Supported unary operator:

-, e. g. -x

Arbitrary unary and binary functions are also supported: names consist of latin letters, digits and underscores, can't start with digit. Examples:

sin(x)
add(x, y)

Dynamic expression code generation

On JVM

kmath-ast JVM module supports runtime code generation to eliminate overhead of tree traversal. Code generator builds a special implementation of Expression<T> with implemented invoke function.

For example, the following code:

import space.kscience.kmath.asm.compileToExpression
import space.kscience.kmath.operations.DoubleField

"x^3-x+3".parseMath().compileToExpression(DoubleField)

… leads to generation of bytecode, which can be decompiled to the following Java class:

import java.util.*;
import kotlin.jvm.functions.*;
import space.kscience.kmath.asm.internal.*;
import space.kscience.kmath.complex.*;
import space.kscience.kmath.expressions.*;

public final class CompiledExpression_45045_0 implements Expression<Complex> {
    private final Object[] constants;

    public Complex invoke(Map<Symbol, ? extends Complex> arguments) {
        Complex var2 = (Complex)MapIntrinsics.getOrFail(arguments, "x");
        return (Complex)((Function2)this.constants[0]).invoke(var2, (Complex)this.constants[1]);
    }
}

For LongRing, IntRing, and DoubleField specialization is supported for better performance:

import java.util.*;
import space.kscience.kmath.asm.internal.*;
import space.kscience.kmath.expressions.*;

public final class CompiledExpression_-386104628_0 implements DoubleExpression {
    private final SymbolIndexer indexer;

    public SymbolIndexer getIndexer() {
        return this.indexer;
    }

    public double invoke(double[] arguments) {
        double var2 = arguments[0];
        return Math.pow(var2, 3.0D) - var2 + 3.0D;
    }

    public final Double invoke(Map<Symbol, ? extends Double> arguments) {
        double var2 = ((Double)MapIntrinsics.getOrFail(arguments, "x")).doubleValue();
        return Math.pow(var2, 3.0D) - var2 + 3.0D;
    }
}

Setting JVM system property space.kscience.kmath.ast.dump.generated.classes to 1 makes the translator dump class files to program's working directory, so they can be reviewed manually.

Limitations

The same classes may be generated and loaded twice, so it is recommended to cache compiled expressions to avoid class loading overhead.
This API is not supported by non-dynamic JVM implementations like TeaVM or GraalVM Native Image because they may not support class loaders.

On JS

A similar feature is also available on JS.

import space.kscience.kmath.expressions.Symbol.Companion.x
import space.kscience.kmath.expressions.*
import space.kscience.kmath.operations.*
import space.kscience.kmath.estree.*

MstField { x + 2 }.compileToExpression(DoubleField)

The code above returns expression implemented with such a JS function:

var executable = function (constants, arguments) {
    return constants[1](constants[0](arguments, "x"), 2);
};

JS also supports experimental expression optimization with WebAssembly IR generation. Currently, only expressions inside DoubleField and IntRing are supported.

import space.kscience.kmath.expressions.Symbol.Companion.x
import space.kscience.kmath.expressions.*
import space.kscience.kmath.operations.*
import space.kscience.kmath.wasm.*

MstField { x + 2 }.compileToExpression(DoubleField)

An example of emitted Wasm IR in the form of WAT:

(func \$executable (param \$0 f64) (result f64)
  (f64.add
    (local.get \$0)
    (f64.const 2)
  )
)

Limitations

ESTree expression compilation uses eval which can be unavailable in several environments.
WebAssembly isn't supported by old versions of browsers (see https://webassembly.org/roadmap/).

Rendering expressions

kmath-ast also includes an extensible engine to display expressions in LaTeX or MathML syntax.

Example usage:

import space.kscience.kmath.ast.*
import space.kscience.kmath.ast.rendering.*
import space.kscience.kmath.misc.*

Extensions to MST API: transformations, dynamic compilation and visualization.

src/commonMain/kotlin/space/kscience/kmath/ast/parser.kt : Expression language and its parser
src/jvmMain/kotlin/space/kscience/kmath/asm/asm.kt : Dynamic MST to JVM bytecode compiler
src/jsMain/kotlin/space/kscience/kmath/estree/estree.kt : Dynamic MST to JS compiler
src/commonMain/kotlin/space/kscience/kmath/ast/rendering/MathRenderer.kt : Extendable MST rendering

Artifact:

The Maven coordinates of this project are space.kscience:kmath-ast:0.3.0.

Gradle Groovy:

repositories {
    maven { url 'https://repo.kotlin.link' }
    mavenCentral()
}

dependencies {
    implementation 'space.kscience:kmath-ast:0.3.0'
}

Gradle Kotlin DSL:

repositories {
    maven("https://repo.kotlin.link")
    mavenCentral()
}

dependencies {
    implementation("space.kscience:kmath-ast:0.3.0")
}

Parsing expressions

In this module there is a parser from human-readable strings like "x^3-x+3" (in the more specific reference/ArithmeticsEvaluator.g4) to MST instances.

Supported literals:

Constants and variables (consist of latin letters, digits and underscores, can't start with digit): x, _Abc2.
Numbers: 123, 1.02, 1e10, 1e-10, 1.0e+3—all parsed either as kotlin.Long or kotlin.Double.

Supported binary operators (from the highest precedence to the lowest one):

^
*, /
+, -

Supported unary operator:

-, e. g. -x

Arbitrary unary and binary functions are also supported: names consist of latin letters, digits and underscores, can't start with digit. Examples:

sin(x)
add(x, y)

Dynamic expression code generation

On JVM

kmath-ast JVM module supports runtime code generation to eliminate overhead of tree traversal. Code generator builds a special implementation of Expression<T> with implemented invoke function.

For example, the following code:

import space.kscience.kmath.asm.compileToExpression
import space.kscience.kmath.operations.DoubleField

"x^3-x+3".parseMath().compileToExpression(DoubleField)

… leads to generation of bytecode, which can be decompiled to the following Java class:

import java.util.*;
import kotlin.jvm.functions.*;
import space.kscience.kmath.asm.internal.*;
import space.kscience.kmath.complex.*;
import space.kscience.kmath.expressions.*;

public final class CompiledExpression_45045_0 implements Expression<Complex> {
    private final Object[] constants;

    public Complex invoke(Map<Symbol, ? extends Complex> arguments) {
        Complex var2 = (Complex)MapIntrinsics.getOrFail(arguments, "x");
        return (Complex)((Function2)this.constants[0]).invoke(var2, (Complex)this.constants[1]);
    }
}

For LongRing, IntRing, and DoubleField specialization is supported for better performance:

import java.util.*;
import space.kscience.kmath.asm.internal.*;
import space.kscience.kmath.expressions.*;

public final class CompiledExpression_-386104628_0 implements DoubleExpression {
    private final SymbolIndexer indexer;

    public SymbolIndexer getIndexer() {
        return this.indexer;
    }

    public double invoke(double[] arguments) {
        double var2 = arguments[0];
        return Math.pow(var2, 3.0D) - var2 + 3.0D;
    }

    public final Double invoke(Map<Symbol, ? extends Double> arguments) {
        double var2 = ((Double)MapIntrinsics.getOrFail(arguments, "x")).doubleValue();
        return Math.pow(var2, 3.0D) - var2 + 3.0D;
    }
}

Setting JVM system property space.kscience.kmath.ast.dump.generated.classes to 1 makes the translator dump class files to program's working directory, so they can be reviewed manually.

Limitations

The same classes may be generated and loaded twice, so it is recommended to cache compiled expressions to avoid class loading overhead.
This API is not supported by non-dynamic JVM implementations like TeaVM or GraalVM Native Image because they may not support class loaders.

On JS

A similar feature is also available on JS.

import space.kscience.kmath.expressions.Symbol.Companion.x
import space.kscience.kmath.expressions.*
import space.kscience.kmath.operations.*
import space.kscience.kmath.estree.*

MstField { x + 2 }.compileToExpression(DoubleField)

The code above returns expression implemented with such a JS function:

var executable = function (constants, arguments) {
    return constants[1](constants[0](arguments, "x"), 2);
};

JS also supports experimental expression optimization with WebAssembly IR generation. Currently, only expressions inside DoubleField and IntRing are supported.

import space.kscience.kmath.expressions.Symbol.Companion.x
import space.kscience.kmath.expressions.*
import space.kscience.kmath.operations.*
import space.kscience.kmath.wasm.*

MstField { x + 2 }.compileToExpression(DoubleField)

An example of emitted Wasm IR in the form of WAT:

(func \$executable (param \$0 f64) (result f64)
  (f64.add
    (local.get \$0)
    (f64.const 2)
  )
)

Limitations

ESTree expression compilation uses eval which can be unavailable in several environments.
WebAssembly isn't supported by old versions of browsers (see https://webassembly.org/roadmap/).

Rendering expressions

kmath-ast also includes an extensible engine to display expressions in LaTeX or MathML syntax.

Example usage:

import space.kscience.kmath.ast.*
import space.kscience.kmath.ast.rendering.*
import space.kscience.kmath.misc.*

Extensions to MST API: transformations, dynamic compilation and visualization.

src/commonMain/kotlin/space/kscience/kmath/ast/parser.kt : Expression language and its parser
src/jvmMain/kotlin/space/kscience/kmath/asm/asm.kt : Dynamic MST to JVM bytecode compiler
src/jsMain/kotlin/space/kscience/kmath/estree/estree.kt : Dynamic MST to JS compiler
src/commonMain/kotlin/space/kscience/kmath/ast/rendering/MathRenderer.kt : Extendable MST rendering

Artifact:

The Maven coordinates of this project are space.kscience:kmath-ast:0.3.0.

Gradle Groovy:

repositories {
    maven { url 'https://repo.kotlin.link' }
    mavenCentral()
}

dependencies {
    implementation 'space.kscience:kmath-ast:0.3.0'
}

Gradle Kotlin DSL:

repositories {
    maven("https://repo.kotlin.link")
    mavenCentral()
}

dependencies {
    implementation("space.kscience:kmath-ast:0.3.0")
}

Parsing expressions

In this module there is a parser from human-readable strings like "x^3-x+3" (in the more specific reference/ArithmeticsEvaluator.g4) to MST instances.

Supported literals:

Constants and variables (consist of latin letters, digits and underscores, can't start with digit): x, _Abc2.
Numbers: 123, 1.02, 1e10, 1e-10, 1.0e+3—all parsed either as kotlin.Long or kotlin.Double.

Supported binary operators (from the highest precedence to the lowest one):

^
*, /
+, -

Supported unary operator:

-, e. g. -x

Arbitrary unary and binary functions are also supported: names consist of latin letters, digits and underscores, can't start with digit. Examples:

sin(x)
add(x, y)

Dynamic expression code generation

On JVM

kmath-ast JVM module supports runtime code generation to eliminate overhead of tree traversal. Code generator builds a special implementation of Expression<T> with implemented invoke function.

For example, the following code:

import space.kscience.kmath.asm.compileToExpression
import space.kscience.kmath.operations.DoubleField

"x^3-x+3".parseMath().compileToExpression(DoubleField)

… leads to generation of bytecode, which can be decompiled to the following Java class:

import java.util.*;
import kotlin.jvm.functions.*;
import space.kscience.kmath.asm.internal.*;
import space.kscience.kmath.complex.*;
import space.kscience.kmath.expressions.*;

public final class CompiledExpression_45045_0 implements Expression<Complex> {
    private final Object[] constants;

    public Complex invoke(Map<Symbol, ? extends Complex> arguments) {
        Complex var2 = (Complex)MapIntrinsics.getOrFail(arguments, "x");
        return (Complex)((Function2)this.constants[0]).invoke(var2, (Complex)this.constants[1]);
    }
}

For LongRing, IntRing, and DoubleField specialization is supported for better performance:

import java.util.*;
import space.kscience.kmath.asm.internal.*;
import space.kscience.kmath.expressions.*;

public final class CompiledExpression_-386104628_0 implements DoubleExpression {
    private final SymbolIndexer indexer;

    public SymbolIndexer getIndexer() {
        return this.indexer;
    }

    public double invoke(double[] arguments) {
        double var2 = arguments[0];
        return Math.pow(var2, 3.0D) - var2 + 3.0D;
    }

    public final Double invoke(Map<Symbol, ? extends Double> arguments) {
        double var2 = ((Double)MapIntrinsics.getOrFail(arguments, "x")).doubleValue();
        return Math.pow(var2, 3.0D) - var2 + 3.0D;
    }
}

Setting JVM system property space.kscience.kmath.ast.dump.generated.classes to 1 makes the translator dump class files to program's working directory, so they can be reviewed manually.

Limitations

The same classes may be generated and loaded twice, so it is recommended to cache compiled expressions to avoid class loading overhead.
This API is not supported by non-dynamic JVM implementations like TeaVM or GraalVM Native Image because they may not support class loaders.

On JS

A similar feature is also available on JS.

import space.kscience.kmath.expressions.Symbol.Companion.x
import space.kscience.kmath.expressions.*
import space.kscience.kmath.operations.*
import space.kscience.kmath.estree.*

MstField { x + 2 }.compileToExpression(DoubleField)

The code above returns expression implemented with such a JS function:

var executable = function (constants, arguments) {
    return constants[1](constants[0](arguments, "x"), 2);
};

JS also supports experimental expression optimization with WebAssembly IR generation. Currently, only expressions inside DoubleField and IntRing are supported.

import space.kscience.kmath.expressions.Symbol.Companion.x
import space.kscience.kmath.expressions.*
import space.kscience.kmath.operations.*
import space.kscience.kmath.wasm.*

MstField { x + 2 }.compileToExpression(DoubleField)

An example of emitted Wasm IR in the form of WAT:

(func \$executable (param \$0 f64) (result f64)
  (f64.add
    (local.get \$0)
    (f64.const 2)
  )
)

Limitations

ESTree expression compilation uses eval which can be unavailable in several environments.
WebAssembly isn't supported by old versions of browsers (see https://webassembly.org/roadmap/).

Rendering expressions

kmath-ast also includes an extensible engine to display expressions in LaTeX or MathML syntax.

Example usage:

import space.kscience.kmath.ast.*
import space.kscience.kmath.ast.rendering.*
import space.kscience.kmath.misc.*

Packages

space.kscience.kmath.asm

jvm

space.kscience.kmath.ast

common

space.kscience.kmath.ast.rendering

common

space.kscience.kmath.estree

space.kscience.kmath.wasm