/**
* Rounds {@code term} to the specfiied precision and exponent range.
*
* <p>Method is undefined if either integer is less than 2 because 2 is the minimum precision and
* exponent. Two exponents must be used to store zero/subnormal/infinity/nan, so 4 is the minimum
* number of distinct exponents a float can have. MPFR does not support floats with 1 bit of
* precision. bits of the float.
*/
public static FloatToken round(
FloatToken term, IntToken precision, IntToken exponent, TermContext context) {
if (precision.intValue() < 2 || exponent.intValue() < 2) {
return null;
}
return FloatToken.of(
term.bigFloatValue()
.round(new BinaryMathContext(precision.intValue(), exponent.intValue())),
exponent.intValue());
}
/**
* Get the number of bits of exponent to use to compute the arithmetic operation.
*
* <p>Currently only floats with the same precision and exponent range can be used in a
* calculation. Users will have to cast floating point types manually using round() if they wish.
*/
private static int getExponent(FloatToken term1, FloatToken term2) {
if (term1.exponent() != term2.exponent()) {
throw new IllegalArgumentException(
"mismatch exponent: "
+ "first argument exponent is represented on "
+ term1.exponent()
+ " bits "
+ "while second argument exponent is represented on "
+ term2.exponent()
+ "bits");
}
return term1.exponent();
}
/**
* Get the {@link BinaryMathContext} object to use to compute the arithmetic operation.
*
* <p>Currently only floats with the same precision and exponent range can be used in a
* calculation. Users will have to cast floating point types manually using round() if they wish.
*/
private static BinaryMathContext getMathContext(FloatToken term1, FloatToken term2) {
getExponent(term1, term2);
if (term1.bigFloatValue().precision() != term2.bigFloatValue().precision()) {
throw new IllegalArgumentException(
"mismatch precision: "
+ "first argument precision is represented on "
+ term1.bigFloatValue().precision()
+ " bits "
+ "while second argument precision is represented on "
+ term2.bigFloatValue().precision()
+ "bits");
}
return getMathContext(term1);
}
public static FloatToken int2float(
IntToken term, IntToken precision, IntToken exponent, TermContext context) {
return FloatToken.of(
new BigFloat(
term.bigIntegerValue(),
new BinaryMathContext(precision.intValue(), exponent.intValue())),
exponent.intValue());
}
/**
* Get the {@link BinaryMathContext} object to use to compute the arithmetic operation. Uses
* {@link RoundingMode#HALF_EVEN} and the precision and exponent range of the {@link FloatToken}.
*/
private static BinaryMathContext getMathContext(FloatToken term) {
return new BinaryMathContext(term.bigFloatValue().precision(), term.exponent());
}
public static BoolToken isNaN(FloatToken term, TermContext context) {
return BoolToken.of(term.bigFloatValue().isNaN());
}
public static FloatToken minValue(
IntToken precision, IntToken exponentBits, TermContext context) {
BinaryMathContext mc = new BinaryMathContext(precision.intValue(), exponentBits.intValue());
return FloatToken.of(BigFloat.minValue(mc.precision, mc.minExponent), exponentBits.intValue());
}
public static FloatToken rem(FloatToken term1, FloatToken term2, TermContext context) {
return FloatToken.of(
term1.bigFloatValue().remainder(term2.bigFloatValue(), getMathContext(term1, term2)),
getExponent(term1, term2));
}
public static FloatToken floor(FloatToken term, TermContext context) {
return FloatToken.of(
term.bigFloatValue().rint(getMathContext(term).withRoundingMode(RoundingMode.FLOOR)),
term.exponent());
}
public static IntToken exponentBits(FloatToken term, TermContext context) {
return IntToken.of(term.exponent());
}
public static BitVector<?> significand(FloatToken term, TermContext context) {
BinaryMathContext mc = getMathContext(term);
return BitVector.of(
term.bigFloatValue().significand(mc.minExponent, mc.maxExponent), mc.precision);
}
public static BoolToken gt(FloatToken term1, FloatToken term2, TermContext context) {
return BoolToken.of(term1.bigFloatValue().greaterThan(term2.bigFloatValue()));
}
public static IntToken precision(FloatToken term, TermContext context) {
return IntToken.of(term.bigFloatValue().precision());
}
/**
* Floating point equality. Uses {@link BigFloat#equalTo(BigFloat)} and not {@link
* BigFloat#equals(Object)} in order to preserve the behavior that -0.0 ==Float 0.0 and NaN
* =/=Float NaN. ==K can be used to compare identity on floating point numbers.
*/
public static BoolToken eq(FloatToken term1, FloatToken term2, TermContext context) {
return BoolToken.of(term1.bigFloatValue().equalTo(term2.bigFloatValue()));
}
public static FloatToken min(FloatToken term1, FloatToken term2, TermContext context) {
return FloatToken.of(
BigFloat.min(term1.bigFloatValue(), term2.bigFloatValue(), getMathContext(term1, term2)),
getExponent(term1, term2));
}
public static FloatToken atan(FloatToken term, TermContext context) {
return FloatToken.of(term.bigFloatValue().atan(getMathContext(term)), term.exponent());
}
public static FloatToken root(FloatToken term1, IntToken term2, TermContext context) {
return FloatToken.of(
term1.bigFloatValue().root(term2.intValue(), getMathContext(term1)), term1.exponent());
}
public static FloatToken unaryMinus(FloatToken term, TermContext context) {
return FloatToken.of(term.bigFloatValue().negate(getMathContext(term)), term.exponent());
}
public static IntToken exponent(FloatToken term, TermContext context) {
BinaryMathContext mc = getMathContext(term);
return IntToken.of(term.bigFloatValue().exponent(mc.minExponent, mc.maxExponent));
}
public static BoolToken le(FloatToken term1, FloatToken term2, TermContext context) {
return BoolToken.of(term1.bigFloatValue().lessThanOrEqualTo(term2.bigFloatValue()));
}
public static BoolToken sign(FloatToken term, TermContext context) {
return BoolToken.of(term.bigFloatValue().sign());
}
/**
* Rounds {@code term} to an integer by truncating it. Function is only defined on ordinary
* numbers (i.e. not NaN or infinity).
*/
public static IntToken float2int(FloatToken term, TermContext context) {
return IntToken.of(
term.bigFloatValue()
.rint(getMathContext(term).withRoundingMode(RoundingMode.DOWN))
.toBigIntegerExact());
}
public static FloatToken sub(FloatToken term1, FloatToken term2, TermContext context) {
return FloatToken.of(
term1.bigFloatValue().subtract(term2.bigFloatValue(), getMathContext(term1, term2)),
getExponent(term1, term2));
}
public static FloatToken mul(FloatToken term1, FloatToken term2, TermContext context) {
return FloatToken.of(
term1.bigFloatValue().multiply(term2.bigFloatValue(), getMathContext(term1, term2)),
getExponent(term1, term2));
}