How to create a bar chart in D3? - d3.js

I need help creating a bar chart, just a normal bar chart.
I have 5 objects, each with their own 10 fields. I want to create a side-by-side bar layout where the x axis labels are the 10 fields. Above the ith field should be a rectangle for each 5 object with each height corresponding to that objects data for that field. Each object has its own distinctive color.
I've spend 4+ hours and I've got nothing. Google reveals nothing that helps. Note: the rectangles of the bar chart should be vertical.
Edit: I'm not getting a lot of help. The answers have been unhelpful, though no fault of the authors. So here's my situation. I'm reading a JSON. The format of the JSON
[
...
{
"RowID":85,
"Name":"Tormore",
"B":2,
"S":2,
"S2":1,
"M":0,
"T":"0",
"H":1,
"S":0,
"W":1,
"N":2,
"Malty":1,
"Fruity":0,
"Floral":0
}
...
]
There are a total of 86 JSON pieces of data. That is, there 86 RowID's. I need to only work with 5. There needs to be 5 colors or however many rowID's I want to work with. The x-axis are the "B", "S" ... "Floral" from the JSON. So there should be "clumps" of 5 bars (colored corresponding to "Name") for each "B", ... "Floral" piece of data. The end goal is to make it easy for the user to visually compare 5 things according to their attributes.
I cannot make this work with the given examples. I've been working on this for at least 6 hours. I'm at my wits end.

It is tough to interpret questions at times...I thought the user might want a grouped bar chart :-) Anyways, I borrowed this graph from Mike and cooked up this UPDATED fiddle with appropriate variable names. If that is what you want, you can add more fields and objects and, of course, change the values appropriately. (The color scale may have to be touched as well.)
Some of the fake data:
var data = [
{"Field":"Field1","Object1":"2704659","Object2":"4499890"},
{"Field":"Field2","Object1":"2027307","Object2":"3277946"},
...

Related

Group by multiple dimensions recursively in dc.js?

dc.js has been great, and now I'm trying to understand how to use it for data with multiple dimensions.
I have time series data (csv), which contains the number of people that fit a certain attribute on a given day - e.g. the number of brown-haired people age 65+. A simplified version of it looks like this (There are 5 options for hair color, 5 for age group, and about 200 dates):
Date, Hair Color, 0-18, 19-39, 40-64, 65+
1/1/21, Brown, 5, 3, 10, 2
1/1/21, Blonde, 15, 2, 4, 1
1/2/21, Brown, 2, 8, 0, 2
1/2/21, Blonde, 11, 6, 7, 4
...
I'd like to be able to plot the cumulative counts over time for each sub-population. The complication is that I'd like to show
A plot aggregated by hair color
(so summing over all age groups), which can then be toggled (ideally by clicking on one of the lines) to show:
A plot for a given hair color
disaggregated by age group.
(Note that in the mockups, I'm normalizing counts to show it as a cumulative percentage. I've been doing that calculation straightforwardly with valueAccessors.)
My question is: how do I create the dimensions and groups to create these plots?
I'd prefer not to create individual variables for each age group (I'd like it to be generic enough to expand to finer categories). But I'm having trouble understanding how to use reduce and filters to achieve my desired outcome.
Also, should I be doing it all as linecharts in a compositeChart, or in a series chart? There is the added wrinkle that I plan to then annotate the chart with extra trendlines added in from d3.
Thanks!
The series chart is a convenience class that generates a composite chart underneath.
It allows you to specify your data using a 2D key, where one component is the key to be used for the X values in the chart, and one component is another key to be used for splitting the data into multiple layers - lines, in your case. You also give it the "prototype" of the layer chart, in the form of a function that returns a partially-initialized chart.
It sounds like you are on the right track, so I won't attempt to give a complete answer, just a few hints. Please feel free to follow up in the comments, and I will edit this answer to fill in details.
Flattening the data
You will probably want to flatten your data so that there is only one value per row, i.e. structure it with an Age column and a Value column. This is a general best practice for working with crossfilter.
It's possible to work with the data as you have it, but
you won't be able to filter by age, since filtering in crossfilter is by row
aggregating across ages will be more complicated, requiring custom reductions
Using multikeys and series chart
Following the series chart example, you might define your dimension as
const colorDateDimension = cf.dimension(d => [d['Hair Color'], d.Date]);
Now any group on this dimension will aggregate by both hair color and date.
Now if you're using the series chart, you can extract the components with
chart
.seriesAccessor(({key}) => key[0])
.keyAccessor(({key}) => key[1])
You could use the third parameter of the series chart chart function to determine the color or dash style of the layer, e.g.:
const dashStyles = {
'0-18': [3,1],
'19-29': [4,1,1,1],
// ...
};
.chart(function(c, _, subkey) {
return new dc.LineChart(c).dashStyle(dashStyles[subkey]);
})
Interaction
dc.js does not natively support the kind of drill-down you are describing. It would be easier to have one chart which is by hair color and another chart which is by age. Then when no hair color is selected, the age chart will show all hair colors, and when no age is selected, the hair color chart will show all ages.
If you want drill-down as you describe, you will have to write custom code to apply the filter and swap the chart definition when a hair color is clicked. It's not terribly complicated but please ask a follow-up question if you can't figure it out - it's better to keep SO questions on a single topic.
Annotating with D3
This part is pretty simple no matter how you implement the charts.
You will implement a pretransition handler and use chart.selectAll to add the content you need. There are many examples here on SO, so I won't go into it here.
Conclusion
I hope this gets you started. I've answered your specific question and given some hints about other assumptions or implicit questions within your question. It will be some work to get the results you want, but it is definitely possible.

D3JS Change TSV Data Column Ordering

I've just draw a stacked-area-chart with D3JS.
This is my referral implementation
I also need to dynamically swap the ordering of the layers.
I think that there isn't a way to do it dynamically without redrawing (or is there any? :D )
Actually i'm trying to map the data to a new header column, but this implies the redrawing.
Let me show you an example:
Here is the TSV header ['date', 'columnA', 'columnB', 'columnC']
Every column, except of 'date', represent the % of area for that sample.
I would like to dynamically rearrange the area layers, but I'm pretty sure that I also need to parse again the data with a new header
eg: ,
['date', 'columnA', 'columnB', 'columnC']
-map to-
['date','columnB', 'columnC', 'columnA']
and then draw the result.
I'm doing it right? Thanks for your support, cheers.
This is the line that defines the array that will be passed to the stack() function:
var keys = data.columns.slice(1);
Right now, this is the array:
["Google Chrome","Internet Explorer","Firefox","Safari","Microsoft Edge","Opera","Mozilla","Other/Unknown"]
But you can sort it anyway you want. For instance, sorting by alphabetic order:
keys.sort();
Which gives us:
["Firefox","Google Chrome","Internet Explorer","Microsoft Edge","Mozilla","Opera","Other/Unknown","Safari"]
Here is the result: https://bl.ocks.org/anonymous/6a339ed0731a70bb234af150ee6b4a99
Here is another one, with a random permutation (refresh the page to see diferent orders): https://bl.ocks.org/anonymous/662f99901219b8907030ec3c84363f3a
Pay attention to this: the order in the stacked area chart is now different, but the colours don't keep the same for each browser (that is, each stacked area). That's because d3.scaleOrdinal(d3.schemeCategory10) assigns the colours in a first-come, first served basis.

DC.js Line Chart - no line being displayed

Need to display line in a line-chart , with the ability to move the tiles, to see a max bitrate value line, to see labels and axis pointers on hover, grouped with a table and time Slider.Y dimension needs to display "bitrate total" or "bitrate Avg" (as defined in code). X dimension needs to display 15 min interval in scope of weeks.
I can upload my data into a table but not into the line graph. I can see points on the graph using .renderDataPoints() but no lines.
I checked the data - could not find any null/NaN values being returned, not using any old version of colors.
The code can be found in https://jsfiddle.net/dani2011/bu2ag0f7/8/. Tried to replace my CSV with var data but nothing is being displayed at the moment in the fiddle. The code as whole is displayed in https://groups.google.com/forum/#!topic/dc-js-user-group/MEslyF2RWRI
Any help would be greatly appreciated.
Here's my go-to-answer for how to put data into a jsFiddle. Basically it's easiest to stick it in an unused tag in the HTML. bl.ocks.org / blockbuilder.org is easier for this.
Here's a fork of your fiddle with the data loaded that way:
http://jsfiddle.net/gordonwoodhull/bu2ag0f7/17/
I also had to remove the spaces from the column names, because those got d3.csv confused and caused the BITRATE calculations to fail.
There was also some stray code inside the renderlet which was failing with a complaint about dim not existing.
The main reason why data was not displaying was because the input groups were not producing usable aggregated data. Your data is very close together in time, so aggregating by week would aggregate everything.
The way to debug this is to put a breakpoint or a console.log before the chart initialization and look at the results of group.all()
In this case bitrateWeekMinIntervalGroupMove and minIntervalWeekBitrateGroup were returning an array with one key/value pair. No lines can be drawn with one point. :)
It looks like you originally wanted to aggregate by 15 minute intervals, so let's get that working.
For whatever reason, there are two levels of aggregation in crossfilter, the dimension level and the group level. The dimension will have first crack at generating a key, and then the group will further refine these keys.
Your min15 function will map each time-key to the 15-minute mark before it, but it needs data that is higher than 15 minutes in resolution. So let's put these groups on the dateDimension, which hasn't already been mapped to a lower resolution:
var minIntervalWeekBitrateGroup = dateDimension.group(min15).reduceSum(function (d) {
return +d.BITRATE
});
var bitrateWeekMinIntervalGroupMove = dateDimension.group(min15).reduce(
...
Great, now there are 30 data points. And it draws lines.
I made the dots a bit smaller :) because at 30 pixels it was hard to see the lines.
Zooming in using the range chart reveals more of lines:
There still seem to be glitches in the reduce function (or somewhere) because the lines drop to zero when you zoom in too far, but hopefully this is enough to get you moving again.
My fork of your fiddle: http://jsfiddle.net/gordonwoodhull/bu2ag0f7/25/

D3.js: Need help grabbing data for tooltip

I've got a graph of small multiples with line charts. All is spiffy, except I cannot figure out how to get the tooltip to grab the data I need it to.
The sample and the code is at http://bl.ocks.org/emagee/8b2f557396d6f16ba65f. The tooltip code starts at line 198, with the toolTip variable declared just above that. The tooltip itself is working awesomely, but I cannot figure out how to get the tooltip to show the "date" and "count" variables. I did figure out how to get the "subject" in tool tip, but that is redundant, as you will see.
Specifically, my problem stems from not knowing how to skip a level as I dig deeper into the object -- "key" is the first level, then "values", then an unnamed construct, THEN the data I need ("date" and "count").
Any guidance on how to get from "key" to the "date" and "count" data would be most appreciated. I do understand that it may be more of a basic JS problem than a D3.js problem, but I'm a bit shaky with both!
Addendum (and, I'm afraid, a second question) -- I'm also wondering now if part of the problem is that I'm accessing the entire line/path -- as opposed to individual points. Should I perhaps overlay some appropriately sized, invisible circles/points on the lines and have the tooltip try to take readings from those...
First question you have to ask is do you want the date and count of where they moused over or do you want the date and count of the closest point to where they moused over? I'm assuming the later, so that's what I'll answer.
To do this, I'd use a combination of invert and a bisector:
.on("mouseover", function(s) {
var xDate = x.invert(d3.mouse(this)[0]), //<-- give me the date at the x mouse position
bisect = d3.bisector(function(d) { return d.date; }).left, //<-- set up a bisector to search the array for the closest point to the left
idx = bisect(s.values, xDate); //<-- find that point given our mouse position
You can now use:
s.values[idx].date
s.values[idx].count
Here's a working example.

dc.js heatmap expanding data

I am trying to show machine states over time. Part of this is to reproduce/automate a report that used to be done by hand. It consists of coloring 2minute 'time slices' in Excel based on what the machine is doing.
(Sorry, not enough reputation to post a picture, but it is a classic heatmap where the state drives the color. Some non DC-JS fiddle: http://jsfiddle.net/ww6Lbnc5/4/)
I was able to generate most of what I want in the following jsfiddle:
http://jsfiddle.net/hwhfxz2t/14/
See fiddle for code.
The total state duration (for selected time frame) is shown in the pieChart, followed by the individual state lines and then the heatmap that people are used to. (the ZOOM and date selection buttons do not work in the fiddle but are there to select specific data ranges or zoom in if you like).
The line charts uses the original representation of the states, which consists of a time the state is entered and a duration.
In order to make the heat map work, I had to (I think) take the original data and convert it into individual minute chunks and mark them with a state. So for instance the original data specifying:
RUN state starting 14:30 for 300 seconds
becomes:
14:30=RUN, 14:31=RUN, 14:32=RUN, 14:33=RUN and 14:34=RUN
The code in lines 233-297 loops through the original data and generates a new one that does this. In cases where there is more than one state within a given minute, the last state survives.
This works okay but it seems that this code is exactly what is normally done in group().reduce(add,remove,init). But in this case I need to add multiple timeslots depending on the duration of a state.
Also, because it is now using a different crossfilter, maps do not update each other.
Here are my questions related to this:
Can I display a heatmap without supplying information for all individual
'cells'? (i.e. straddle cells based on a value, similar to rowspan in a table)
Can I add multiple values at once inside group().reduce()?
Is there an easy way to invert the yAxis so 0 is at the top?
When clicking a row in the heatmap, it selects a column and vice-versa?
I'm not sure if this should be in the crossfilter group. If so please ignore my rambling. If someone knows how to keep the charts linked by grouping better, please let me know.
--Nico
Concerning Question 3:
DC.js heatmaps currently do not support custom order functions on axis but there is a pull request that has been merged into the developing branch and should be accessible to the public soon.
You could manually edit the dc.js file to set the sorting in heatmaps to a custom function. In the latest (2.0.0-beta10) version it is the following line:
rowValues.sort(d3.ascending);
and accordingly
colValues.sort(d3.ascending);

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