So I have a notebook with many cells that I want to update continuously, at a given interval, say 1 update per second (sync doesn’t matter). I’ve been doing this with multiple Promise.delay/yield calls, but the code gets messy quickly. Is there a way to do this more cleanly (in a single place) for …

yeah I would have once cell name tick with the yield/delay. Then on every cell just reference the tick variable. e.g. myothercell = { tick // cause recalc on tick, but otherwise ignore the variable value ... other stuff }

Mmm, that is very nice, thank you. But what if I wanted them to update one at a time? I’m thinking about graphical elements primarily, where I don’t want a big flash every second where everything changes at once…

Does this help How Observable Runs / Observable / Observable ?

Thanks for that, I now have a better understanding of the design thinking. And I may well be cutting against its grain, but I still think the use case is… useful. Ideally I could provide an array of cell-names (the slowly updating graphical elements), and have each updated every K milliseconds, but …

Q: is there a way to programmatically force an update of a cell from another cell (without cross-cell references ) ? Not in an idiomatic way Q: can one access the graph of cells directly ? Checkout Notebook visualizer / Observable | Observable I don’t think there is an easy way to do it as a…

Hmm, I see how it might be done by iteration over the runtime _variables property and finding the desired cells, but, as you say, it is working quite against the observable grain… One other question: is there a way to disable propagation of updates to downstream references of a cell? My guess is t…

Good question. I have thought about whether it’s possible to slow down update frequency too. It is possible! here is a PoC Observable's 'now' temporal spacing is 60 or 30 frames per second. / Tom Larkworthy / Observable You can return an unresolved promise to “skip” updates. Another useful express…

[image] dhowe: is there a way to disable propagation of updates to downstream references of a cell? If the update is triggered by a parent cell, then no: [image] Fighting Against (Run-)Time A futile attempt to delay or prevent the execution of dependent cells. Context / discussio…

If the update is triggered by a parent cell, then no: Yes you can, return new Promise(() => {}) in the child to skip propagating an update when a parent updates. “The previously-resolved value continues to be visible to other cells until the newly-yielded value resolves: in other words, a genera…

[image] tomlarkworthy: Yes you can, return new Promise(() => {}) in the child to skip propagating an update when a parent updates. Imo that’s only marginally useful, since any downstream cell will still be invalidated. So it’s fine for one-off cells that only compute a value, but any generato…

Refresh cells on a timer

Help

mootari January 13, 2021, 7:52pm 13

I’ve added a section to Fighting Against (Run-)Time / Fabian Iwand / Observable - notice how the ticks_since_hours_invalidation generator cell never counts up higher than 2.

Topic		Replies	Views
Change words in paragraph on timer ?	12	700	February 21, 2021
Cell memoization Help	4	626	November 24, 2020
Calling a function defined in one cell from another cell Help	2	2381	March 18, 2018
First Class Cells Feedback	13	838	April 23, 2021
how to control cell updating in response to value changes in dependency cells? Help	7	1899	October 21, 2020

Refresh cells on a timer

Related topics