How to create a time based bar chart in LibreOffice Calc, similar to a Gantt chart?

[MaliTaus]

Hi,

I have searched high and low for a non-stacked, horizontal bar chart that shows sleep cycles (number and duration). The best way to describe what I want to do is visually - please see attached screenshots of some example base data and a mock up of the chart I want to produce. The data is all good: time format and appropriate time formulas, count the cycles, etc.

I want dates on the Y axis and hours of the day on the X axis. The chart also needs to expand downwards as I add more data.

I have read similar topics in ask.libreoffice.org such as the one below but can’t see what I want:
How to create a chart with date-time values. - #17 by Wtx_Engineer

Thanks!

Version: 7.4.7.2 / LibreOffice Community
Build ID: 40(Build:2)
CPU threads: 4; OS: Linux 6.1; UI render: default; VCL: gtk3
Locale: en-AU (en_AU.UTF-8); UI: en-US
Debian package version: 4:7.4.7-1+deb12u8
Calc: threaded

[Lupp]

Do you know this thread in a different forum? It is a bit bloated, but contains some reasonable suggestions. There is also an as-if-solution by myself without a chart using conditional formatting for the visualisation. It’s built along a concept I once “invented” to solve a task of the original Gantt-type.
Anyway you should reconsidser the structure of your data.
Currently you start with something you consider a date, but even the first tranch only ends on the next day. The scheme would get completely confusing if your first “tranch of sleep” once starts after midnight.
Next flaw is the fix maximum number of tranches given for any specific “day”.
For a consistent solution it’s next to necessary that every tranch gets its own row as the data set. Each such row will in your case contain a date (real dates always are YYYY-MM-DD) to which the tranch shall be assigned.
In your case the visualisation should be placed then on a dedicated sheet where each row represents an “assigned date” and displays all the tranches for this date.
In any related or similar case “points in time” must be described by complete date-time-values. Real time is NOT cyclic!