Principal Part

The principal part at of a function

is the portion of the Laurent series consisting of terms with negative degree. That is,

is the principal part of at . has an essential singularity at, if and only if the principal part is an infinite sum.

Famous quotes containing the words principal and/or part:

    The principal point of cleverness is to know how to value things just as they deserve.
    François, Duc De La Rochefoucauld (1613–1680)

    Friendship demands a religious treatment. We talk of choosing our friends, but friends are self-elected. Reverence is a great part of it.
    Ralph Waldo Emerson (1803–1882)