Skip to content

Commit

Permalink
Fixes Hipparchus-Math#281: introducing default implementations in Cal…
Browse files Browse the repository at this point in the history 
…culusFieldElement and inheritors
  • Loading branch information
@Serrof
Serrof committed Nov 14, 2023
1 parent 43dcbbd commit c3ef7ba
Show file tree
Hide file tree
Showing 17 changed files with 1,484 additions and 272 deletions.
3 changes: 3 additions & 0 deletions hipparchus-core/src/changes/changes.xml
View file
Expand Up @@ -50,6 +50,9 @@ If the output is not quite correct, check for invisible trailing spaces!
</properties>
<body>
<release version="3.1" date="TBD" description="TBD.">
<action dev="serrof" type="add" issue="issues/281">
Add default implementations in CalculusFieldElement and inheritors.
</action>
<action dev="serrof" type="add" issue="issues/280">
Add square method to FieldElement.
</action>
Expand Down
112 changes: 85 additions & 27 deletions hipparchus-core/src/main/java/org/hipparchus/CalculusFieldElement.java
View file
Expand Up @@ -25,6 +25,7 @@
import org.hipparchus.util.FastMath;
import org.hipparchus.util.FieldSinCos;
import org.hipparchus.util.FieldSinhCosh;
import org.hipparchus.util.MathArrays;

/**
* Interface representing a <a href="http://mathworld.wolfram.com/Field.html">field</a>
Expand All @@ -42,7 +43,9 @@ public interface CalculusFieldElement<T extends FieldElement<T>> extends FieldEl
* @return Archimedes constant π
* @since 2.0
*/
T getPi();
default T getPi() {
return newInstance(FastMath.PI);
}

/** Create an instance corresponding to a constant real value.
* @param value constant real value
Expand All @@ -54,25 +57,45 @@ public interface CalculusFieldElement<T extends FieldElement<T>> extends FieldEl
* @param a right hand side parameter of the operator
* @return this+a
*/
T add(double a);
default T add(double a) {
return add(newInstance(a));
}

/** '-' operator.
* @param a right hand side parameter of the operator
* @return this-a
*/
T subtract(double a);
default T subtract(double a) {
return subtract(newInstance(a));
}

/** {@inheritDoc} */
@Override
default T subtract(T a) {
return add(a.negate());
}

/** '&times;' operator.
* @param a right hand side parameter of the operator
* @return this&times;a
*/
T multiply(double a);
default T multiply(double a) {
return multiply(newInstance(a));
}

/** {@inheritDoc} */
@Override
default T multiply(int n) {
return multiply((double) n);
}

/** '&divide;' operator.
* @param a right hand side parameter of the operator
* @return this&divide;a
*/
T divide(double a);
default T divide(double a) {
return divide(newInstance(a));
}

/**
* Return the exponent of the instance, removing the bias.
Expand Down Expand Up @@ -119,23 +142,31 @@ T hypot(T y)

/** {@inheritDoc} */
@Override
T reciprocal();
default T divide(T a) {
return multiply(a.reciprocal());
}

/** Square root.
* @return square root of the instance
*/
T sqrt();
default T sqrt() {
return rootN(2);
}

/** Cubic root.
* @return cubic root of the instance
*/
T cbrt();
default T cbrt() {
return rootN(3);
}

/** N<sup>th</sup> root.
* @param n order of the root
* @return n<sup>th</sup> root of the instance
*/
T rootN(int n);
default T rootN(int n) {
return pow(1. / n);
}

/** {@inheritDoc} */
@Override
Expand All @@ -147,13 +178,17 @@ default T square() {
* @param p power to apply
* @return this<sup>p</sup>
*/
T pow(double p);
default T pow(double p) {
return pow(newInstance(p));
}

/** Integer power operation.
* @param n power to apply
* @return this<sup>n</sup>
*/
T pow(int n);
default T pow(int n) {
return pow((double) n);
}

/** Power operation.
* @param e exponent
Expand Down Expand Up @@ -202,12 +237,16 @@ T pow(T e)
* @return [sin(this), cos(this)]
* @since 1.4
*/
FieldSinCos<T> sinCos();
default FieldSinCos<T> sinCos() {
return new FieldSinCos<>(sin(), cos());
}

/** Tangent operation.
* @return tan(this)
*/
T tan();
default T tan() {
return sin().divide(cos());
}

/** Arc cosine operation.
* @return acos(this)
Expand Down Expand Up @@ -255,16 +294,20 @@ T atan2(T x)
*/
T sinh();

/** Combined hyperbolic sine and sosine operation.
/** Combined hyperbolic sine and cosine operation.
* @return [sinh(this), cosh(this)]
* @since 2.0
*/
FieldSinhCosh<T> sinhCosh();
default FieldSinhCosh<T> sinhCosh() {
return new FieldSinhCosh<>(sinh(), cosh());
}

/** Hyperbolic tangent operation.
* @return tanh(this)
*/
T tanh();
default T tanh() {
return sinh().divide(cosh());
}

/** Inverse hyperbolic cosine operation.
* @return acosh(this)
Expand All @@ -284,12 +327,16 @@ T atan2(T x)
/** Convert radians to degrees, with error of less than 0.5 ULP
* @return instance converted into degrees
*/
T toDegrees();
default T toDegrees() {
return multiply(FastMath.toDegrees(1.));
}

/** Convert degrees to radians, with error of less than 0.5 ULP
* @return instance converted into radians
*/
T toRadians();
default T toRadians() {
return multiply(FastMath.toRadians(1.));
}

/**
* Compute a linear combination.
Expand All @@ -308,8 +355,13 @@ T linearCombination(T[] a, T[] b)
* @return <code>&Sigma;<sub>i</sub> a<sub>i</sub> b<sub>i</sub></code>.
* @throws MathIllegalArgumentException if arrays dimensions don't match
*/
T linearCombination(double[] a, T[] b)
throws MathIllegalArgumentException;
default T linearCombination(double[] a, T[] b) throws MathIllegalArgumentException {
final T[] newInstances = MathArrays.buildArray(getField(), a.length);
for (int i = 0; i < a.length; i++) {
newInstances[i] = newInstance(a[i]);
}
return linearCombination(newInstances, b);
}

/**
* Compute a linear combination.
Expand All @@ -335,7 +387,9 @@ T linearCombination(double[] a, T[] b)
* @see #linearCombination(double, FieldElement, double, FieldElement, double, FieldElement)
* @see #linearCombination(double, FieldElement, double, FieldElement, double, FieldElement, double, FieldElement)
*/
T linearCombination(double a1, T b1, double a2, T b2);
default T linearCombination(double a1, T b1, double a2, T b2) {
return linearCombination(newInstance(a1), b1, newInstance(a2), b2);
}

/**
* Compute a linear combination.
Expand Down Expand Up @@ -365,7 +419,9 @@ T linearCombination(double[] a, T[] b)
* @see #linearCombination(double, FieldElement, double, FieldElement)
* @see #linearCombination(double, FieldElement, double, FieldElement, double, FieldElement, double, FieldElement)
*/
T linearCombination(double a1, T b1, double a2, T b2, double a3, T b3);
default T linearCombination(double a1, T b1, double a2, T b2, double a3, T b3) {
return linearCombination(newInstance(a1), b1, newInstance(a2), b2, newInstance(a3), b3);
}

/**
* Compute a linear combination.
Expand Down Expand Up @@ -401,7 +457,10 @@ T linearCombination(double[] a, T[] b)
* @see #linearCombination(double, FieldElement, double, FieldElement)
* @see #linearCombination(double, FieldElement, double, FieldElement, double, FieldElement)
*/
T linearCombination(double a1, T b1, double a2, T b2, double a3, T b3, double a4, T b4);
default T linearCombination(double a1, T b1, double a2, T b2, double a3, T b3, double a4, T b4) {
return linearCombination(newInstance(a1), b1, newInstance(a2), b2, newInstance(a3), b3,
newInstance(a4), b4);
}

/** Get the smallest whole number larger than instance.
* @return ceil(this)
Expand Down Expand Up @@ -454,7 +513,9 @@ T linearCombination(double[] a, T[] b)
* @param sign the sign for the returned value
* @return the instance with the same sign as the {@code sign} argument
*/
T copySign(double sign);
default T copySign(double sign) {
return copySign(newInstance(sign));
}

/**
* Check if the instance is infinite.
Expand Down Expand Up @@ -490,9 +551,6 @@ default double norm() {
}

/** absolute value.
* <p>
* Just another name for {@link #norm()}
* </p>
* @return abs(this)
*/
T abs();
Expand Down
67 changes: 67 additions & 0 deletions hipparchus-core/src/main/java/org/hipparchus/analysis/differentiation/Derivative.java
View file
Expand Up @@ -18,13 +18,20 @@

import org.hipparchus.CalculusFieldElement;
import org.hipparchus.exception.MathIllegalArgumentException;
import org.hipparchus.util.FastMath;

/** Interface representing both the value and the differentials of a function.
* @param <T> the type of the field elements
* @since 1.7
*/
public interface Derivative<T extends CalculusFieldElement<T>> extends CalculusFieldElement<T> {

/** {@inheritDoc} */
@Override
default double getReal() {
return getValue();
}

/** Get the number of free parameters.
* @return number of free parameters
*/
Expand Down Expand Up @@ -64,4 +71,64 @@ public interface Derivative<T extends CalculusFieldElement<T>> extends CalculusF
T compose(double... f)
throws MathIllegalArgumentException;

/** {@inheritDoc} */
@Override
default T log10() {
return log().divide(FastMath.log(10.));
}

/** {@inheritDoc} */
@Override
default T pow(T e) {
return log().multiply(e).exp();
}

/** {@inheritDoc} */
@Override
default T cosh() {
return (exp().add(negate().exp())).divide(2);
}

/** {@inheritDoc} */
@Override
default T sinh() {
return (exp().subtract(negate().exp())).divide(2);
}

/** {@inheritDoc} */
@Override
default T acos() {
return asin().negate().add(getPi().divide(2));
}

/** {@inheritDoc} */
@Override
default T ceil() {
return newInstance(FastMath.ceil(getValue()));
}

/** {@inheritDoc} */
@Override
default T floor() {
return newInstance(FastMath.floor(getValue()));
}

/** {@inheritDoc} */
@Override
default T rint() {
return newInstance(FastMath.rint(getValue()));
}

/** {@inheritDoc} */
@Override
default T ulp() {
return newInstance(FastMath.ulp(getValue()));
}

/** {@inheritDoc} */
@Override
default T sign() {
return newInstance(FastMath.signum(getValue()));
}

}

0 comments on commit c3ef7ba

Please sign in to comment.