code: public static BigComplex valueOfPolar(BigDecimal radius, BigDecimal angle, MathContext mathContext) {
  		if (radius.signum() == 0) {
  			return ZERO;
  		}
  
  		return valueOf(
  				radius.multiply(BigDecimalMath.cos(angle, mathContext), mathContext),
  				radius.multiply(BigDecimalMath.sin(angle, mathContext), mathContext));
  	}
docs: Returns a complex number with the specified polar {@link BigDecimal} radius and angle using the specified {@link MathContext}.
  
  @param radius the {@link BigDecimal} radius of the polar representation
  @param angle the {@link BigDecimal} angle in radians of the polar representation
  @param mathContext the {@link MathContext} used to calculate the result
  @return the complex number