The phrase "a function at a" is not complete and lacks context, making it difficult to determine its correctness in written English.
It could be used in mathematical or programming contexts where you are referring to a function evaluated at a specific point or variable.
Example: "The value of the function at a is crucial for determining the limit."
Alternatives: "a function evaluated at" or "a function of a".
Six years ago, Tim George Jr. was working for a Manhattan restaurant that was catering a function at a sports-car race at Lime Rock Park in Connecticut.
"The players went to the Rebels v Lions game with their team-mates and after the match they went back to a function at a club, with other Rebels guys.
For our problem here, the Laplacian operator on a function at a given point is 1/4 times the value of the function at each of the four neighboring points minus the value of the function at the given point.
The Laplacian operator (cf. Hans #14) is used to describe how the value of a function at a given point is related to the value at its neighboring points; harmonic functions are those for which the Laplacian is zero.
"The players went to the Rebels v Lions game with their team-mates and after the game they went back to a function at a club, with other Rebels guys.
In this approximate numerical method, the spatial derivatives of a function at a point are expressed as weighted sums of the function values of a group of supporting points.
One evening in Maputo, at a function at the Soviet Embassy, he began a conversation with a woman named Alla Protassova.
We follow Dorian to a job as a waiter servicing a function at some glossily vacant intersection of the art and fashion worlds.
One guest that night, Iwona Rachelski, a television producer who lives in Clifton, had attended a function at Crystals banquet room with a friend a few weeks earlier.
Smith broke the mould again in 1997 when he and Jabri were invited as a couple to attend a function at Buckingham Palace, sparking much press interest.
His first experience came when he was mistakenly given a glass of champagne at a function at the Royal Festival Hall.
