// Result computes the square root of the variance.
func (a *stdDevAggregate) Result() Datum {
variance := a.agg.Result()
if variance == DNull {
return variance
}
switch t := variance.(type) {
case *DFloat:
return NewDFloat(DFloat(math.Sqrt(float64(*t))))
case *DDecimal:
decimal.Sqrt(&t.Dec, &t.Dec, decimal.Precision)
return t
}
panic(fmt.Sprintf("unexpected variance result type: %s", variance.ResolvedType()))
}
},
},
"sqrt": {
floatBuiltin1(func(x float64) (Datum, error) {
if x < 0 {
return nil, errSqrtOfNegNumber
}
return NewDFloat(DFloat(math.Sqrt(x))), nil
}),
decimalBuiltin1(func(x *inf.Dec) (Datum, error) {
if x.Sign() < 0 {
return nil, errSqrtOfNegNumber
}
dd := &DDecimal{}
decimal.Sqrt(&dd.Dec, x, decimal.Precision)
return dd, nil
}),
},
"tan": {
floatBuiltin1(func(x float64) (Datum, error) {
return NewDFloat(DFloat(math.Tan(x))), nil
}),
},
"trunc": {
floatBuiltin1(func(x float64) (Datum, error) {
return NewDFloat(DFloat(math.Trunc(x))), nil
}),
decimalBuiltin1(func(x *inf.Dec) (Datum, error) {