// Abs sets z to the absolute value of x if x is finite and returns z.
func (z *Big) Abs(x *Big) *Big {
if x.form != finite {
return z
}
if x.isCompact() {
z.compact = arith.Abs(x.compact)
} else {
z.mantissa.Abs(&x.mantissa)
}
z.scale = x.scale
z.ctx = x.ctx
z.form = finite
return z
}
// MulPow10 computes 10 * x ** n and a bool indicating whether
// the multiplcation was successful.
func MulPow10(x int64, n int32) (p int64, ok bool) {
if x == 0 || n <= 0 || x == c.Inflated {
return x, true
}
if n < pow.Tab64Len && n < pow.ThreshLen {
if x == 1 {
return pow.Ten64(int64(n))
}
if arith.Abs(int64(n)) < pow.Thresh(n) {
p, ok := pow.Ten64(int64(n))
if !ok {
return 0, false
}
return Mul(x, p)
}
}
return 0, false
}
// Mul returns x * y and a bool indicating whether the addition
// was successful.
func Mul(x, y int64) (prod int64, ok bool) {
prod = x * y
return prod, ((arith.Abs(x)|arith.Abs(y))>>31 == 0 || prod/y == x)
}