code: public static BigFloat negate(BigFloat x) {
  		if (x.isSpecial())
  			if (x.isInfinity())
  				return x == POSITIVE_INFINITY ? NEGATIVE_INFINITY : POSITIVE_INFINITY;
  			else
  				return NaN;
  		return x.context.valueOf(x.value.negate());
  	}
docs: Returns the {@link BigFloat} that is <code>- this</code>.
  
  @param x the value to negate
  
  @return the resulting {@link BigFloat}
  
  @see BigDecimal#negate(MathContext)