Would like to use length (from d3.nest) as radius - d3.js

I'm having a mental block about using the result of:
.rollup(function(leaves) { return leaves.length;})
as the radius of a circle in a scatter plot. My complete code (and sample data) is in a plunk here https://plnkr.co/edit/Cwuce6inLV5jouCWTFfN
The scatter works with a static value of 5 but I'd like to use value based on the .rollup from the d3.nest as explained in this other SO question I had: Capturing leaves.length value from d3.nest
I think I'm missing a key concept about in this section of code:
d3.tsv("etds_small.tsv", function(error, dataset) {
dataset.forEach(function(d) {
if(deptlist.indexOf(d.dept) == -1) deptlist.push(d.dept);
if(years.indexOf(d.year) == -1) years.push(d.year);
})
var deptYearCount = d3.nest()
//.key(function(d) { return d.college;} )
.key(function(d) { return d.dept})
.key(function(d) { return d.year })
.rollup(function(leaves) { return leaves.length;})
.map(dataset);
console.log(dataset); // retains the college, dept, and year labels
console.log(deptYearCount); // replaces labels with "key"
x.domain(years.sort(d3.ascending));
y.domain(deptlist.sort(d3.ascending));
//console.log(y.domain());
//console.log(x.domain());
svg.selectAll(".dot")
.data(dataset) //should this be deptYearCount from the d3.nest above?
.enter().append("circle")
.attr("class", "dot")
.attr("r", 5) // Would like to use length (from d3.nest) as radius
//.attr("r", function(d) {return d.values.length*1.5;}) works with .data(debtYearCount)
.style("opacity", 0.3)
.style("fill", "#e31a1c" )
.attr("cx", function(d) {
return x(d.year);
})
.attr("cy", function(d) {
return y(d.dept);
});

Give this a try for your radius:
.attr("r", function(d) {return Object.keys(deptYearCount[d.dept]).length*1.5;})
Because you are using .map(dataset) instead of .entries(dataset), d3.next() is returning one-big-object instead of an array of objects. That one-big-object does not contain a property called values.
Updated explanation:
First, look at the structure of the object deptYearCount. It has property names like Earth Sciences., Education., etc.
Our d3 data is iterating over an array of objects. Each object has property dept that looks like Earth Sciences., Education., etc.
So, deptYearCount[d.dept] is getting us to the correct property within deptYearCount.
For example, at one round of our iteration we are looking at deptYearCount["Education."]. That turns out to be another object with properties like 2007,2008, etc. Therefore, the number of properties in deptYearCount["Education."] is the value we want for the radius.
How do we find the number of properties of deptYearCount["Education."]? One way is the Object.keys(someObject) function. It returns an array of strings corresonding to the property names, and we just need its .length.

Related

d3js - how to filter the array with values and pass in to data?

I am getting data from backend, where some of the values are 0. I don't want to create the circle for those values.
I understand, I need to use a filter, but I don't have any idea how to use that.
Here is my code:
var circles = city.selectAll("circle")
.data(function(d) {
return d.values //this is a array length 20 how to filter that? i need only with values more than 0
})
.enter()
.append("circle")
.attr("r", 3.5)
.attr("cx", function(d, i) {
return x(d.date)
})
.attr("cy", function(d) {
return y(d.temperature)
})
.style('cursor', 'pointer')
.attr("fill", "transparent")
.attr("stroke", "yellow")
.attr("stroke-width", 0);
If d.values is an array you can use Array.prototype.filter() to extract all values different from 0 from it. The following will bind only non-zero values and create circles only for these:
.data(function(d) {
return d.values.filter(function(v) { return v != 0; });
})
Firstly, I'm assuming that you meant something more like .data(dataFromBackend, function (d) { return d.values; }), otherwise there's no bind!
Anyway, to do what you're describing, and making the assumption that you're not bothered about having the 0-values in the bind at all, you can simply do:
filteredData = backendData.filter(function (d) {
return d.value != 0;
});
There's a detailed reference for .filter here, but briefly, the function passed to .filter is called for every element in backendData, with each element referred to by d in the usual way. The return value should be boolean (true or false), but will work with anything, using 'truthiness'. Any element the function returns something 'truthy' for will be included in the final array (filteredData in my example), any element the function returned something 'falsey' will not.

D3.js: Transferring the value of one attribute to another attribute, for a specific FDG node?

I'm using a force directed graph that appends circles to each node.
As part of the node creation, I first set the radius "r" of each node circle to a default and consistent value (defaultNodeSize = 10). This successfully draws a cluster where all related nodes are the same size.
// Append circles to Nodes
node.append("circle")
.attr("x", function(d) { return d.x; })
.attr("y", function(d) { return d.y; })
.attr("r", function(d) { if (d.id==focalNodeID) { return centerNodeSize; } else { return defaultNodeSize; } } ) // <---------------------------- Radius "r" set HERE!!!!
.style("fill", "White") // Make the nodes hollow looking
.attr("type_value", function(d, i) { return d.type; })
.attr("color_value", function(d, i) { return color_hash[d.type]; })
.attr("rSize", function(d, i) { return d.rSize; }) // <------------------ rSize HERE!!!!
.attr("id", "NODE" )
.attr("class", function(d, i) {
var str = d.type;
var strippedString = str.replace(/ /g, "_")
//return "nodeCircle-" + strippedString; })
if (d.id==focalNodeID) { return "focalNodeCircle"; }
else { return "nodeCircle-" + strippedString; }
})
.style("stroke-width", 5) // Give the node strokes some thickness
.style("stroke", function(d, i) { return color_hash[d.type]; } ) // Node stroke colors
.call(force.drag);
Also, upon creation, I set an attribute called "rSize", which specifies that node's absolute magnitude. Each node has a different rSize and rSize is different than the defaultNodeSize. The purpose of rSize is so that I can access it, later, and dynamically change the circle's radius from it's defaultNodeSize to it's rSize (or the reverse) allowing each node to expand or contract, based on controllers.
In a separate controller function, I later select all nodes I want to apply the new rSize to. Selecting them is easy...
var selectedNodeCircles = d3.selectAll("#NODE");
However, I don't know what the syntax is to read each node's rSize and apply rSize to that specific node that's being changed. I would think that it's something like...
selectedNodeCircles.("r", function(){ return this.attr("rSize"); });
In other word's, I'd like to retrieve that specific node's "rSize" attribute value and set the attribute "r" to the value retrieved from "rSize".
Any idea of what the correct syntax is to do this?
Thanks for any help you can offer!
You are looking for the getAttribute() function.
So something like this should work for you:
selectedNodeCircles.attr("r", function() {return this.getAttribute("rSize")})
Remember that this in the function, is the circle itself and hence simply an element in the DOM, to the best of my understanding.
You can confirm this by simply printing out this using console.log(this) right before the result statement.
Hope this helps.

Adding point and value to line chart... how to color the point like the line?

I've started from the multiline example http://bl.ocks.org/mbostock/3884955
I extended it to show the dots along the line, but I'm not able to give to the circle the same color of the line...
I'm really new in d3.js and I really need an advice.
here the example page: http://www.danielepennati.com/d3/linea.html
I've change some variable name to make the script more general so there is some difference with the original example code. the main one is the name of the variable that contain the mapped data: it is "column" and not "cities"
d3.tsv(surce_data, function(error, data) {
color.domain(d3.keys(data[0]).filter(function(key) { return key !== "id"; }));
var column = color.domain().map(function(name) {
return {
name: name,
values: data.map(function(d) {
return {id: d.id, value: +replace(d[name])};
})
};
});
the second main difference is the x axsis: in my code it is ordinal and not linear.
so to draw the line the code is:
var tracciato = svg.selectAll(".line-group")
.data(column)
.enter().append("g")
.attr("class", "line-group");
tracciato.append("path")
.attr("class", "line")
.attr("d", function(d) { return line(d.values); })
.style("stroke", function(d) { return color(d.name); });
to make the points along the line I've wrote this code:
var point = tracciato.append("g")
.attr("class", "line-point");
point.selectAll('circle')
.data(function(d,i){ return d.values})
.enter().append('circle')
.attr("cx", function(d, i) {
return x(i) + x.rangeBand() / 2;
})
.attr("cy", function(d, i) { return y(d.value) })
.attr("r", 5);
I'd link the points color be the same of the line, but the problem is the colors are assigned to the "column" object. I don't know how to give to each new circle within the same column the same column color...
I don't know if my problem is clear, please ask me if you need any more specification.
Thanks

d3.js Color coding grid based on data from a csv file

I built a grid of squares based on the example given in http://bl.ocks.org/bunkat/2605010. Now i am trying to color code each of the cells in the grid based on the data from csv file. Say for example, i have a csv file with data as
cell, col1
1,2
2,3
3,2
4,1
cells are colored based on data in col1. Like cell 1 colored with blue, cell 2 colored with green, cell 3 colored again with blue, cell 4 colored with red.
I have been trying something like this, but it doesn't work. Please help?
d3.text("frame.csv", function(datasetText) {
var parsedCSV = d3.csv.parseRows(datasetText);
var col = row.selectAll(".cell")
.data(function (d) { return d; })
.enter().append("svg:rect")
.attr("class", "cell")
.attr("x", function(d) { return d.x; })
.attr("y", function(d) { return d.y; })
.attr("width", function(d) { return d.width; })
.attr("height", function(d) { return d.height; })
.style("fill", function(d) { return color(parsedCSV[d].col1); })
.style("fill", '#FFF')
.style("stroke", '#555');
});
There is a 'fill' attribute that you can use to set the fill color of the item. Like other d3 functions, you can pass it either a value, or a function which returns the value. It sounds like you would want to use a function which will determine what colour you want, then return that value. Note that you will have to return it as a string (so wrapped in quotes) as either '#660066' or 'rgb(166,0,166)'. You could also use rgba if you wish.
After this it is just a matter of writing your function to return the right colour, which I can't really help you with as I don't know what you want.
Also this may be a duplicate of d3js fill color.
I found my mistake. I had to use d3.csv.parse(string) instead of d3.csv.parseRows(string[, accessor]) function since my csv file contained column names. Thanks for the help. Appreciate it.

D3 why doesn't my data update?

In this code, http://enjalot.com/inlet/4124664/
of which the main part is:
function render(data) {
var nodz = svg.selectAll(".node")
.data(data);
nodz.enter().append("g")
.attr("class", "node")
.attr("id", function(d) { return "id"+d[0]+d[1]; })
.attr("x",0)
.attr("y", 0)
.attr("transform", function(d) {
return "translate(" + x(d[0]) + "," + y(d[1]) + ")";
})
.append("text")
.attr("x", 0)
.attr("y", 0)
.attr("stroke", "black")
.text(function(d) {return d[2]; });
// update
nodz.selectAll("text")
.text(function(d) {
return d[2]; });
// another go
d3.selectAll("text")
.text(function(d) {
return d[2]; });
}
// data in form [x pos, y pos, value to display]
var nodes = [[0,0,0],[1,1,0],[1, -1,0],[2,0,0], [2,2,0]];
render(nodes);
nodes2 = [[0,0,1],[1,1,1],[1, -1,1],[2,0,1], [2,2,1], [2, -2,1]];
render(nodes2);
I call the code to draw some nodes twice.
I expect it to draw five nodes with a value of zero in the first pass,
Then I add another item to the list and update all the values to 1 so expect to see all the values change to 1 and a new node appear. Instead, I'm only seeing the last one being set to 1. I've tried adding a unique id to bind the node to the data but this isn't working. Also tried reselecting to see if the data is now bound. In all the tutorials I've been through, just calling the selectAll().data() part updates the data, what am I missing?
The second optional argument to .data() is a function that tells d3 how to match elements. That's where you need to compare your IDs, see the documentation. That said, it should work without IDs in your case as it matches by index by default.
The problem with updating the text is that after calling .selectAll() you need to call .data() again to let d3 know what you want to match to that selection (i.e. that the new data should be bound to the old data).

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