2735: Coordinate Plane Closure

2023-02-08T17:57:14Z

Popstar403: Clarification

{{comic
| number = 2735
| date = February 8, 2023
| title = Coordinate Plane Closure
| image = coordinate_plane_closure_2x.png
| imagesize = 271x376px
| noexpand = true
| titletext = 3D graphs that don't contact the plane in the closure area may proceed as scheduled, but be alert for possible collisions with 2D graph lines that reach the hole and unexpectedly enter 3D space.
}}

==Explanation==
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This comic is a "Math Notice," which is presumably a warning or reminder for mathematicians or others who interact with the field of mathematics. Specifically, this one advises those who are using the coordinate plane to avoid drawing any graphs in the area with a hole until the damage is patched or fixed. This comic likens the coordinate plane to the earth, and invents the concept of Math Notices, similar to Notices to the Airmen/Marine Notices in aeronautics and navigation.

{{w|Coordinate planes}} are used in math for drawing graphs. The joke here is that a small section has been "closed for maintenance," likening the concept of a coordinate plane to an actual physical platform used by math, which is therefore vulnerable to damage such as is shown in the comic. In reality, the coordinate plane cannot be damaged as it is not a tangible thing.{{citation needed}}

Closure in mathematics is a term relating to sets, specifically operations on sets, and a coordinate plane is a particular set of numbers. A set is closed under an operation if all the "answers" to the operation are also in the set. The coordinate plane is said to be closed under vector addition for example - adding together any two coordinates produces another coordinate in the plane. Many functions and operators may be said to have closure on the real plane, and this comic may be a pun on that term. However, if there actually is a hole in the plane, then suddenly the plane will no longer exhibit closure.

The title text clarifies some of the unwanted effects of drawing a graph into the hole, stating that two-dimensional graph lines might accidentally become three-dimensional and interfere with the graphs made there.

==Transcript==

:<big>⚠️ Math Notice ⚠️</big>[emojis written without color]

:The coordinate plane will be closed Thursday between (1.5, 1) and (2, 1.5) to repair a hole.

:[A coordinate graph is shown, with a gray hole between (1.5, 1) and (2, 1.5). There are small fractures around the hole. The hole is highlighted with two dots in the corners of a hollow rectangle with split border lines.]

:If your graph uses this area, please postpone drawing until Friday or transform it to different coordinates.

{{comic discussion}}

[[Category:Math]]

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2735: Coordinate Plane Closure