func (d Decimal) Atan() Decimal {
	return Decimal{
		decimal: d.decimal.Atan(),
		vars:    atan + leftParen + d.vars + rightParen,
		formula: atan + leftParen + d.formula + rightParen,
	}
}
// Atan returns the arctangent, in radians, of x.
Atan returns the arctangent, in radians, of x.
// Atan returns the arctangent in radians of x .
func (d Decimal) Atan() Decimal {
	return Decimal{
		decimal: d.decimal.Atan(),
		vars:    atan + leftParen + d.vars + rightParen,
		formula: atan + leftParen + d.formula + rightParen,
	}
}
func ( d Decimal ) Atan ( ) Decimal { return Decimal { decimal : d . decimal . Atan ( ) , vars : atan + leftParen + d . vars + rightParen , formula : atan + leftParen + d . formula + rightParen , } }
Atan returns the arctangent, in radians, of x.
Atan returns the arctangent in radians of x .