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:
“Light, God’s eldest daughter, is a principal beauty in a building.”
—Thomas Fuller (1608–1661)
“Remember that you are an actor in a drama, of such a part as it may please the master to assign you, for a long time or for a little as he may choose. And if he will you to take the part of a poor man, or a cripple, or a ruler, or a private citizen, then may you act that part with grace! For to act well the part that is allotted to us, that indeed is ours to do, but to choose it is another’s.”
—Epictetus (c. 55–135 B.C.)