Fixed part of a linear system (source code)

= Fixed part of a linear system
{title2=$F$}

= Fixed part
{synonym}

For a nonempty <complete linear system of a divisor> on a smooth projective variety, the coefficient of a prime divisor in its fixed part is the minimum of its multiplicities in all members. Multiplication by the section of $F$ identifies the sections of $D-F$ with those of $D$.