2884: Log Alignment

2024-01-23T01:36:40Z

Computerpenguin: added part about real skew log diagrams

{{comic
| number = 2884
| date = January 22, 2024
| title = Log Alignment
| image = log_alignment_2x.png
| imagesize = 351x312px
| noexpand = true
| titletext = A video can have a log scale that's misaligned with both the time AND space axes.
}}

==Explanation==
{{incomplete|Created by a BENDY LOG - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic jokes about how there isn't a rule in math that requires you to align log scale and graph axes. Therefore, the person who drew the graph in the comic decided to make it distorted. According to that person, this graph is still valid. Whilst a plot ''can'' be made according to measures not consistent with the graph axes, especially where [https://www.researchgate.net/figure/Curvature-introduced-by-pen-type-recording-system-Comparison-of-a-raw-seismogram-showing_fig5_364100386 other factors dictate the plotting], it is more usual to make use of {{w|Graph paper#Examples|variant grid systems}} that are directly suited to your intended purpose (and stick to them).

The comic shows a background distribution of straight and parallel (but notably off-orthogonal) lines, such as might normally define the log-magnitude on a log-log or semi-log graph. But there are no perpendicular gradations ''and'' the bar graph drawn upon it appears to have no relation with the background, drawn distorted in an almost [https://en.wikipedia.org/wiki/Salvador_Dal%C3%AD Dalíesque] manner as if a projection of one twisted in 3d space, both its bars and the base/vertical axes seem to have no relation to to the supposed underlying log-scale. However, with the slight exception of the bar tops crossing the log lines at an angle, and the curved vertical axis having {{w|Graduation (scale)|graduation ticks}} that bear no linear ''or'' log relation with the intersecting background, the distorted bars only travel unidirectionally across the underlying parallels and ''could'' feasibly be read as indicating a definitive magnitude (or range) of some kind. Or at least could with number-labels to give an idea of what values to associate with each log-line. That two bars appear from outside the frame of the comic (the base axis having fallen off the bottom) might not even matter, so long as we can work out what quality or sample each of the bars represents (being similarly unlabeled).

Skewed log charts are real and occur in fields of science with useful applications. For example, a diagram called a "Skew-T Log-P" chart depicts the relationship between temperature and pressure of a parcel of air in the atmosphere. On this chart, the x-axis is skewed with relation to the rest of the graph, and its isotherms, or lines of equal temperature, slant diagonally upwards and to the right of the diagram. The y-axis is normal and represents temperature on a log scale. A more detailed explanation can be found [https://www.noaa.gov/jetstream/upperair/skew-t-log-p-diagrams here].

The title text further reinforces the concept of misalignment by stating that the time axis at the bottom of a video can be misaligned with the video itself and a log scale in that video.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Distorted bar graph on top of gray log scale lines in the background that are slightly tilted, with the lower ends on the left]

:[Caption below the panel:]
:There's actually no rule in math that says your log scales have to be aligned with your graph axes.

{{comic discussion}}

[[Category:Math]]
[[Category:Bar charts]]

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2884: Log Alignment