how to create a time chart in echarts - charts

I'd like to create a time chart
more or less like the chrome devTool's network panel \
consider each row is a machine in a cluster
then from left to right the time passes
each rectangular box is a time span
Question 1: what is the best way to do this in echarts?
Question 2: how can I get the effective width? i.e. the hard coded 551
I'm currently doing it using type:scatter, using symbolSize to draw the rectangles
const effectiveWidth=551
symbolSize: function (val) { return [val[2]*effectiveWidth/(data.max-data.min),10]; }
-- EDIT --
waterfall chart(helpfully pointed out by the comment https://echarts.apache.org/handbook/en/how-to/chart-types/bar/waterfall/) seems working, I initially didn't choose it because I have to create a shadow series(transparent, stacked) for each and every series. is there a way to directly control where each rectangle is placed(like scatter chart)?
for Question2, sorry I should have mentioned dataZoom, when zooming, the effective width changes, but it is not reflected using convertToPixel("grid",...), maybe I shouldn't be using "grid"?
I was using the following code(ec is an echart instance):
const computeScale=(w)=>(ec.convertToPixel("grid",[w,0])[0]-ec.convertToPixel("grid",[0,0])[0])/w
symbolSize: (val)=>[Math.max(0,(scale??=computeScale(86400000))*zoomScale*val[2]-1),10],
but it has some flaws:
the symbol size is in pixel, the val(intended width) is in value(xAxis), thus the conversion is needed. can we tell echart to somehow use the same coordinate system directly without the conversion?
when zooming, the above conversion(using convertToPixel) doesn't work, thus I have to introduce another zoomScale value let zoomScale=1;ec.on("datazoom",(ev:any)=>void(zoomScale=100/(ev.end-ev.start)))(BTW ev.start and ev.end is double value, not integer, so it shouldn't have too much precision problem, but it do have
all these conversion have precision problems, especially zoomScale, it often creates rect overlapping artifacts
https://stackblitz.com/edit/qwik-starter-dhqv1i?file=src/routes/index.tsx
zoom using the handles at the bottom of the preview page to see the artifacts

Related

tableau adjust marks size using number

In Marks, click Size and there pops a slider where I can adjust the size of a shape. But how to accurately control the size, is there some property with numbers to accurately control it? I have two sheets to show something similar and I want to display exactly the same sized shapes.
If you want to ensure 'sizes' are the same across two worksheets, I'd suggest snapping the 'size' setting to the center on both, as this is the easiest option to select. You can then use a measure to set the size, if this is desirable, and then the difference in size will be relative on both worksheets.
There isn't a numerical value override for the size slider.
Ben is correct, there isn't yet a numerical value override for the slider. You can use parameters with Min/Max/Sum etc. and a variable to somewhat change the sizes but they have to have multiple entries per line. It is unfortunate that Tableau still doesn't get that people want both a 'relative' sizing system that uses numbers from the dataset and a 'static' sizing system that allows for shapes to be set to '11px' or something along those lines. Yes, you can control that kind of in the dashboard with a vertical and fill entire box etc; but that doesn't address the very real scenario where you want a user to be able to re-size on the fly. Just my two cents.
I ran into this today. Very annoying. Need to keep shapes the same size across all worksheets and therefore same on dashboard.

How to display a big figure with mlpd3 inside jupyter notebook?

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For example, this code generate a graphic, for which you will see only the upper left part:
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Thanks
Edit after comment:
Here is a screenshot of how it is displayed on my machine...
And I would like it to be displayed just as it is on yours !
So I guess the problem comes from elsewhere... do you have any idea of how to solve this ?
I hope I do understand your question correctly but in Ipython Notebooks you can only use excisting space and not flip the notebook into wide screen mode or alike. In my notebook the graphic is also displayed like you show.
However, there is an easy fix, simply reduce the figsize to for example (10, 5). The main idea with interactive plotting with mpld3 is that the user can zoom in to specific interesting details. For the presented example it would not make much sense but richer graphs are great to be explored interactively.

How to apply horizontal break to a d3.js bar chart

I am using Rickshaw (based on d3.js) to plot stacked bar charts. The problem is that the first bar is usually way more higher than the others, ruining the visual feedback.
Using logarithmic scale is (I guess) not an option here, because then the proportions between stacks in a bar will get broken. I wanted to introduce a horizontal break like in following image:
However, I cannot find any out-of-the box feature of Rickshaw or d3.js to do something like this. Any suggestions on how to make one?
This would require quite a bit of additional work. Here's an outline of what you would have to do.
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You basically need to create two graphs that are aligned with each other to give the impression that there's just one. If you keep that in mind, doing it shouldn't be too difficult.
Here's a quick and dirty proof of concept that uses the linear scale's .clamp(true) to prevent the bars from becoming too long for values outside the domain.
The d3fc-discontinuous-scale component adapts any other scale (for example a d3 linear scale) and adding the concept of discontinuities. These discontinuities are determined via a 'discontinuity provider', which can be used to create one or more 'gaps' in a scale.
For example, to remove a range, you can construct a scale as follows:
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Here is a complete example that shows how to use this to create a 'break' in a scale in order to render values that have large gaps in their overall range.
https://bl.ocks.org/ColinEberhardt/b60919a17c0b14d745c881f48effe681

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I can draw the text character-by-character using PdfContentByte.ShowText() but then it isn't searchable.
I'm now trying to create a PdfTextArray, which would seem to satisfy both of my requirements, but I'm having trouble calculating the correct offsets.
So my first question is: do you agree that PdfTextArray is what I need to do, in order to satisfy both of my original requirements?
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I believe the positioning offset is the distance from the right edge of the previous character to the left edge of the new character, expressed in "thousandths of a unit of text space". That leaves me two problems:
1) How wide is the previous character (in points), as drawn in the specified font & height? (I know where its left edge is, since I drew it there)
2) How do I convert from points to "units of text space"?
I'm not doing any fancy scaling or rotating, so my transformation matrices should all be identity matrices, which should simplify the calculations ...
Thanks,
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How to prevent the fill command in MATLAB from creating boxes without "corners"

I am currently using the fill command in MATLAB to create a graph of boxes that were created using the 'fill' command (the actual code is based off this StackOverflow Question.
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fill(X,Y,MyFaceColor,'FaceAlpha',0.5,'EdgeColor', MyEdgeColor,'LineStyle','','LineWidth',box_line_width,'EdgeAlpha',1)
The function fill appears to leave space for corner markers if they are not explicitly defined. Hence, calling fill with the marker property will solve your problem. However, since markers and linewidths seem to work on different scales, you will have to play around with the marker size to get smooth edges.
Example:
fill(X,Y,'r','FaceAlpha',0.5,'EdgeColor', 'k',...
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