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 office of history I take to be this: to prevent virtuous actions from being forgotten, and that evil words and deeds should fear an infamous reputation with posterity.”
—Tacitus (c. 55–c. 120)
“Great speeches have always had great soundbites. The problem now is that the young technicians who put together speeches are paying attention only to the soundbite, not to the text as a whole, not realizing that all great soundbites happen by accident, which is to say, all great soundbites are yielded up inevitably, as part of the natural expression of the text. They are part of the tapestry, they aren’t a little flower somebody sewed on.”
—Peggy Noonan (b. 1950)