BigComplexMath.sqrt fails on non-positive real numbers

[noeppi-noeppi]

When BigComplexMath.sqrt is invoked with an argument that has a negative or zero real part and a zero imaginary part, it throws an ArithmeticException:

BigComplexMath.sqrt(BigComplex.ONE.negate(), MathContext.DECIMAL64)

Exception in thread "main" java.lang.ArithmeticException: Division undefined
	at java.base/java.math.BigDecimal.divide(BigDecimal.java:1831)
	at ch.obermuhlner.math.big.BigComplex.divide(BigComplex.java:287)
	at ch.obermuhlner.math.big.BigComplexMath.sqrt(BigComplexMath.java:289)

Expected behaviour:

BigComplexMath.sqrt should not throw an ArithmeticException but compute the result (in the above case 0 + 1i) instead.

[eobermuhlner]

The bug is confirmed and I am working on a fix.

Thanks for reporting it.

[nadment]

This should also solve a problem with the ACOS function.

BigDecimalMath.acosh(BigDecimal.ZERO, MathContext.DECIMAL128); >> Illegal sqrt(x) for x < 0: x = -1