lumean / svg-graph2 Goto Github PK

I would like to draw a chart with x labels as integer, and y labels as float number.

I found there is number_format option that can determine the label format.

But it apply to both x labels and y labels.

I think a histogram would be a valuable addition to the available charts. I got started on a prototype yesterday but wanted to gather feedback before putting more work in. Does a histogram sound like a good idea? It can technically be accomplished with the existing bar chart but requires you to calculate the bin count and size yourself.

Here is a link to my fork with my start on a histogram. It's pretty functional at this point but doesn't handle all of the options that other charts do. Let me know what you think.
https://github.com/dansbits/svg-graph2/tree/histogram-chart

rotate_y_labels: 0,

  rotate_y_labels: 0,
  stagger_y_labels: true,

When rotating y labels so they are horizontal, they are either cropped or overlapping the graph.

key_position: :right

key_position: :bottom

Feels like when using :bottom, the legend should be inline rather than in block.

is it possible to create charts with 2 y axis?

I searched in the code and saw no way to choose color without providing a CSS stylesheet.

This is from the bar_horizontal.svg file written by svg-graph2's own test suite (viewed in Chrome 80, Mac OS 10.14 [Mojave]). This isn't desired behavior, right?

This gem uses the gem rexml but the RubyGems page does not list that. We should add rexml as a dependency to this gem.

After I updated to the latest, I noticed that the years along the x axis in one of my graphs were now displaying as 2015.00, 2016.00, etc even though I was passing them in as strings ("2015", "2016", etc).

I think the issue is this line of code:
https://github.com/lumean/svg-graph2/blob/master/lib/SVG/Graph/Graph.rb#L592

which is formatting anything that can be parsed as a float as a number with decimal places, including strings. I fixed it by setting the number_format option to "%g", but I could see other people getting tripped up by this as the default behavior. I think this is a perfectly fine default for numeric data types, but strings should probably be displayed as-is.

Thanks!

As mentioned in #25, I'm doing this on my fork, but will provide a pull request to enable it on the main repo if that's wanted.

I think this is a great library for plotting. One of the better plotting libraries for ruby.

I think it would be a good addition if graphs would display automatically in Jupyter and iRuby. I believe this would be a simple addition of a to_iruby method to the SVG::Graph::Graph class. I'm happy to put up a PR for this but wanted to get feedback on the idea first. Any thoughts?

It looks like Graph#make_datapoint_text writes each datapoint's text twice, once on top of the other, to provide a background and help the text stand out. Unfortunately, one text object uses the class .dataPointLabel, while the other uses .dataPointLabel plus some inline styling to make the background. This is a problem for those of us who use our own CSS to style the SVG graphs, because the inline styling (which, BTW, has the background hard-coded to white) means that it's difficult or impossible to customize the backgrounds to do the right thing.

What I propose, then, is the following (and I'll make a pull request for it hopefully in the next day or so): keep .dataPointLabel on the foreground element, but create a new class called something like .dataPointLabelBackground for the background element, and put the styling there instead of inline. This should keep the graph's current behavior with the default CSS, but make custom CSS easier to apply. Sound good?

Is it possible to place the x-axis on the 0 of the y-axis? Attached is the issue I'm running into.

Right now, the y-axis is placed on the least value of the x-axis.

The assumption so far was, that the divisions of the axis are exactly aligned with the graph borders. Probably it would make sense to decouple this, especially for integer divisions. i.e. to allow some padding before the first or after last division if needed.

graph border should align with min/max_x/y_value when given or else depend on the datapoints and align with the min max values of those.

See also #35

The documentation here gives an ERROR 500: http://www.germane-software.com/software/SVG/SVG::Graph/doc
Hopefully rubygems auto-generate this: https://www.rubydoc.info/gems/svg-graph/2.2.0

Is there any option to create donut pie chart like this https://image-charts.com/chart?cht=pd&chtt=Blend&chs=978x300&chd=t:20,20,30,400,50&chl=20%C2%B0|20%C2%B0|30%C2%B0|40%C2%B0|50%C2%B0&chli=95K&chdl=Expansion|Payroll|Equipment ?

Due to a shift in my priorities, I'm no longer able to invest enough time to thoroughly review and test PRs, not even speaking of active development of this library.

Please reach out if you're interested in continuing to maintain this small and hopefully still useful library project. I'm happy to share repo and gem publish rights.

The following links are now dead:

$ git grep -n germane-software/repositories/
lib/SVG/Graph/Line.rb:45:    # http://www.germane-software/repositories/public/SVG/test/single.rb
lib/SVG/Graph/Pie.rb:39:    # http://www.germane-software/repositories/public/SVG/test/single.rb
lib/SVG/Graph/Plot.rb:58:    # http://www.germane-software/repositories/public/SVG/test/plot.rb
lib/SVG/Graph/Schedule.rb:50:    # http://www.germane-software/repositories/public/SVG/test/schedule.rb
lib/SVG/Graph/TimeSeries.rb:63:    # http://www.germane-software/repositories/public/SVG/test/timeseries.rb

These URLs are dead as well:

http://www.germane-software.com/repositories/...  
https://www.germane-software.com/repositories/...  

First of all, I just wanted to say thanks to @lumean for putting some effort into this gem recently. This is really the only decent ruby graphing library I have found, but it could still use some work. And I'm happy to contribute, as well, because I've been depending on it lately.

Anyway, here is my issue: Often, when I use a key and the labels are somewhat long, they get covered by the pie graph. For example:

There are a few ways this could be fixed or partially fixed:

1. Move the pie graph left depending on the width of the key (hardest but best option, I would think)
2. Add an option for x_offset or something similar to specify the distance from the left so that the pie could be left-aligned
   • Currently this is calculated as (width - diameter) / 2.
3. Add an option to add a maximum width on the key and line break any labels that are longer
4. Add an option to right-align the key

Let me know what you think and I'm happy to contribute a pull request. Thanks!

Data point popups are rendered in the SVG document just after the data point that they're associated with, but before the next data point. Unfortunately, unlike HTML, SVG 1.1 has no z-index attribute, but rather paints elements declared later in the document on top of elements declared earlier. This means that in a closely spaced graph, a popup can appear obscured by the following data point or its label:

So what I propose (and will hopefully submit a PR for soon) is a slightly different rendering process, where the nodes for the data point popups aren't put into the SVG document till after all the data point nodes are written. Does that sound reasonable, or would that cause problems somewhere else?

BTW, I do really appreciate this gem quite a lot. It's making my life much easier on http://covid-tracking-charts.herokuapp.com. @lumean Thanks for maintaining it!

As mentioned in #24, the code in this gem is really hard to work with. I'm planning to refactor the gem to made the code more tractable, probably moving tests to RSpec in the process.

• Translate tests to RSpec
• Make a first refactoring pass to make better use of RSpec features
• Write better tests (many of the existing ones are just smoketests without really checking the functionality)
• Refactor as necessary