Im using d3.js to draw a scatterplot in javascript and this is my first javascript program. The user can draw a click n drag SVGRectangle to calculate the average of the points that get bounded by the rectangle. I have implemented the rectangle drawing part, I'm stuck with the part where I have to determine which points (SVGCircles) are inside the rectangle. Im trying to get all the circle elements in an array allCircles, and then filtering out the circles that are in the rectangle region. However I cannot figure out how to get the coordinates of the circles. The way I did it below doesnt seem to work.
var svg = d3.select("body")
.append("svg")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")");
var allCircles = svg.selectAll("circle.circles"); //circles is the class for all points
//I have to do the following line coz for some reason the entire array comes as one single //element
allCircles = allCircles[0];
for (var j = 0; j < allCircles.length; j++) {
if (allCircles[j].top > startY && allCircles[j].left > startX
&& (allCircles[j].height + allCircles[j].top) < rectHeight + startY
&& (allCircles[j].width + allCircles[j].left) < rectWidth + startX) {
selectedCircles.push(allCircles[j]);
}
}
Any fixes, suggestions, hints, links would be appreciated as Im really short on time !
When selecting objects with D3, you can't access those attributes directly -- use the .attr() function. That is, instead of allCircles[j].top you would do d3.select(allCircles[j]).attr("top") or allCircles[j].getAttribute("top"). Note that you need to have set those attributes explicitly.
The D3 way to do something like that would be to use the .filter() function on your selection, i.e. something like
svg.selectAll("circle.circles")
.filter(function(d) { return d.top > startY && /* etc */; })
.each(function(d) {
// do something with the selected circles
});
Related
I am trying to update a d3 graph when I click on a County on a map. Instead of updating the existing chart, a new graph is created each time. Any ideas of how to rectify this? Code is here: https://github.com/careyshan/d3-graphUpgade
Thanks
This is the part of the code that I am having difficulty with:
on("click", function(d,i){
if(document.getElementById('linechart').childNodes===null){
console.log("Working")
dataNew = data.filter(function( obj ) {
return obj.County == d.properties.NAME_TAG;
console.log(data);
});
dataNew.sort(function(a,b){
// Turn your strings into dates, and then subtract them
// to get a value that is either negative, positive, or zero.
return b.date - a.date;
});
for (var i=1; i<dataNew.length;i++){
dataSel.push(dataNew[i]);
}
}else if(document.getElementById('linechart').childNodes!=null){
//console.log("check")
dataNew = data.filter(function( obj ) {
return obj.County == d.properties.NAME_TAG;
});
dataNew.sort(function(a,b){
// Turn your strings into dates, and then subtract them
// to get a value that is either negative, positive, or zero.
return b.date - a.date;
});
for (var i=1; i<dataNew.length;i++){
dataSel.push(dataNew[i]);
}
}
linechart(dataNew);
console.log(dataNew);
});
A new graph is created each time because on every call to the function linechart() you are appending a new graph (an svg element) to the body of the page.
This is the snippet from your code which appends a new graph each time.
// append the svg obgect to the body of the page
// appends a 'group' element to 'svg'
// moves the 'group' element to the top left margin
var svg = d3.select("body").append("svg")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.append("g")
.attr("id","linechart")
.attr("transform",
"translate(" + margin.left + "," + margin.top + ")");
If you want to update the same chart, just modify your linechart() function to refer to the same svg element. You can achieve this by declaring a global variable for the svg element and use it in your linechart() method like below:
// If graph is not there, create it
if(!svg) {
// append the svg object to the body of the page
//appends a 'group' element to 'svg'
// moves the 'group' element to the top left margin
svg= d3.select("body").append("svg")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.append("g")
.attr("id","linechart")
.attr("transform",
"translate(" + margin.left + "," + margin.top + ")");
}
Note: Declare the svg as a global variable (may be at the starting of the script tag):
var svg;
I have a D3js map built with topojson.js.
var projection = d3.geo.mercator();
Everything works fine, but I am looking for an effect that I cannot manage to achieve. When, zooming the map I would like the pins over it to scale down, But if I scale it down, I need to recalculate their coordinates and I can't find the formula to do so.
Zoom handler
scale = d3.event.scale;
if (scale >= 1) {
main.attr("transform", "translate(" + d3.event.translate + ")
scale(" + d3.event.scale + ")");
}
else {
main.attr("transform", "translate(" + d3.event.translate + ")scale(1)");
}
//43x49 is the size initial pine size when scale = 1
var pins = main.select("#pins").selectAll("g").select("image")
.attr("width", function () {
return 43 - (43 * (scale - 1));
})
.attr("height", function () {
return 49 - (49 * (scale - 1));
})
.attr("x", function () {
//Calculate new image coordinates;
})
.attr("y", function () {
//Calculate new image coordinates;
});
My question is : how do I calculate x and y based on new scale?
I hope I am clear enough.
Thanks for your help
EDIT :
Calculation of initial pins coordinates :
"translate(" + (projection([d.lon, d.lat])[0] - 20) + ","
+ (projection([d.lon, d.lat])[1] - 45) + ")"
-20 and -45 to have the tip of the pin right on the target.
You need to "counter-scale" the pins, i.e. as main scales up/down you need to scale the pins down/up, in the opposite direction. The counter-scale factor is 1/scale, and you should apply it to each of the <g>s containing the pin image. This lets you remove your current width and height calculation from the <image> nodes (since the parent <g>'s scale will take care of it).
However, for this to work properly, you'll also need to remove the x and y attributes from the <image> and apply position via the counter-scaled parent <g> as well. This is necessary because if there's a local offset (which is the case when x and y are set on the <image>) that local offset gets scaled as the parent <g> is scaled, which makes the pin move to an incorrect location.
So:
var pinContainers = main.select("#pins").selectAll("g")
.attr("transform", function(d) {
var x = ... // don't know how you calculate x (since you didn't show it)
var y = ... // don't know how you calculate y
var unscale = 1/scale;
return "translate(" + x + " " + y + ") scale(" + unscale + ")";
})
pinContainers.select("image")
.attr("width", 43)
.attr("height", 49)
// you can use non-zero x and y to get the image to scale
// relative to some point other than the top-left of the
// image (such as the tip of the pin)
.attr("x", 0)
.attr("y", 0)
I would like to disable drag and drop on this SVG element, but failed with several tries,
/// Define drag beavior
var drag = d3.behavior.drag()
.on("drag", dragmove);
function dragmove(d) {
// if the event.x goes over a boundry, trigger "dragend"
if(d3.event.x > 200){
//drag.dragend();
drag.trigger("dragend");
}
var x = d3.event.x;
var y = d3.event.y;
d3.select(this).attr("transform", "translate(" + x + "," + y + ")");
}
svgContainer.call(drag);
JSFiddle - http://jsfiddle.net/nhe613kt/76/
I want disable drag on my chart or matrix you can say, I want it fixed and zoom able.
I am following this jsfiddle - http://jsfiddle.net/typeofgraphic/Ne8h2/4/ but it doesn't has any method
drag.dragend();
//drag.trigger("dragend");
Exception here as it throws - Uncaught TypeError: undefined is not a function
I've fixed you drag capability. You had two zoom variables, the first one called zoomed which was also a variable but wasn't declared until after it was called which wouldn't work. Also called your zoom variable as soon as you made your SVG. Yours was jittery as you appended a 'g' element after you made the SVG and then called your zoom so your zoom was being put on the 'g' element inside your SVG not on your actual SVG.
JSFiddle update : http://jsfiddle.net/nhe613kt/90/
var svgContainer = d3.select("body").append("svg")
.call(zoom) //called earlier
.attr("width", width)
.attr("height", height)
.style("background-color", "black")
.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.right + ")");
Like mentioned in the comments, whats your end goal ? How come you want to disable your drag ? Do you wish to drag each rectangle individually ? If so you'll have to call the drag on each individual rectangle :) Tell me what else you want it to do and ill give it a go :)
I am trying to build a bar graph that I can switch between the amount of data displayed based on a particular length of time. So far the code that I have is this,
var margin = {
top : 20,
right : 20,
bottom : 30,
left : 50
}, width = 960 - margin.left - margin.right, height = 500
- margin.top - margin.bottom;
var barGraph = function(json_data, type) {
if (type === 'month')
var barData = monthToArray(json_data);
else
var barData = dateToArray(json_data);
var y = d3.scale.linear().domain([ 0, Math.round(Math.max.apply(null,
Object.keys(barData).map(function(e) {
return barData[e]['Count']}))/100)*100 + 100]).range(
[ height, 0 ]);
var x = d3.scale.ordinal().rangeRoundBands([ 0, width ], .1)
.domain(d3.entries(barData).map(function(d) {
return barData[d.key].Date;
}));
var xAxis = d3.svg.axis().scale(x).orient("bottom");
var yAxis = d3.svg.axis().scale(y).orient("left");
var svg = d3.select("#chart").append("svg").attr("width",
width + margin.left + margin.right).attr("height",
height + margin.top + margin.bottom).append("g").attr(
"transform",
"translate(" + margin.left + "," + margin.top + ")");
svg.append("g").attr("class", "x axis").attr("transform",
"translate(0," + height + ")").call(xAxis);
svg.append("g").attr("class", "y axis").call(yAxis).append(
"text").attr("transform", "rotate(-90)").attr("y", 6)
.attr("dy", ".71em").style("text-anchor", "end").text(
"Total Hits");
svg.selectAll(".barComplete").data(d3.entries(barData)).enter()
.append("rect").attr("class", "barComplete").attr("x",
function(d) {
return x(barData[d.key].Date)
}).attr("width", x.rangeBand() / 2).attr("y",
function(d) {
return y(barData[d.key].Count);
}).attr("height", function(d) {
return height - y(barData[d.key].Count);
}).style("fill", "orange");
var bar = svg.selectAll(".barHits").data(d3.entries(barData))
.enter().append("rect").attr("class", "barHits").attr(
"x", function(d) {
return x(barData[d.key].Date) + x.rangeBand() / 2
}).attr("width", x.rangeBand() / 2).attr("y",
function(d) {
return y(barData[d.key].Count);
}).attr("height", function(d) {
return height - y(barData[d.key].Count);
}).style("fill", "red");
};
This does a great job displaying my original data set, I have a button set up to switch between the data sets which are all drawn at the beginning of the page. all of the arrays exist but no matter how hard I try I keep appending a new graph to the div so after the button click I have two graphs, I have tried replacing all of the code in the div, using the enter() exit() remove() functions but when using these I get an error stating that there is no exit() function I got this by following a post that someone else had posted here and another one here but to no avail. Any ideas guys?
What you are most likely doing is drawing a new graph probably with a new div each time the button is clicked, one thing you can try doing is to hold on to the charts container element somewhere, and when the button is clicked, you simply clear it's children and re-draw the graphs.
In practice, I almost never chain .data() and .enter().
// This is the syntax I prefer:
var join = svg.selectAll('rect').data(data)
var enter = join.enter()
/* For reference: */
// Selects all rects currently on the page
// #returns: selection
svg.selectAll('rect')
// Same as above but overwrites data of existing elements
// #returns: update selection
svg.selectAll('rect').data(data)
// Same as above, but now you can add rectangles not on the page
// #returns: enter selection
svg.selectAll('rect').data(data).enter()
Also important:
# selection.enter()
The enter selection merges into the update selection when you append or insert.
Okay, I figured it out So I will first direct all of your attention to here Where I found my answer. The key was in the way I was drawing the svg element, instead of replacing it with the new graph I was just continually drawing a new one and appending it to the #chart div. I found the answer that I directed you guys to and added this line in the beginning of my existing barGraph function.
d3.select("#barChart").select("svg").remove();
and it works like a charm, switches the graphs back and forth just as I imagined it would, now I have a few more tasks for the bargraph itself and I can move on to another project.
Thank you all for all of your help and maybe I can return the favor one day!
I have a bubble force chart application, and I've created various instances of it. However I can not seem to scale the bubbles in relation to the height/width of the svg.
http://jsfiddle.net/pPMqQ/138/
I've placed an inverse on the heights/widths to alter the viewport - but it doesn't feel like the right approach to me. Does anyone have any experience as to how to correct this?
var inverseHeight = 1/h * 100000;
var inverseWidth = 1/w * 100000;
var svg = d3.select(selector)
.append("svg")
.attr("class", "bubblechart")
.attr("width", parseInt(w + padding,10))
.attr("height", parseInt(h + padding,10))
.attr('viewBox', "0 0 "+parseInt(inverseWidth,10)+" "+parseInt(inverseHeight,10))
.attr('perserveAspectRatio', "xMinYMid")
.append("g")
.attr("transform", "translate(" + (w/4) + "," + (h/4) + ")");
I've tried to scale the actual bubbles
http://jsfiddle.net/pPMqQ/143/
var scale = methods.width*.005;
Its producing an ideal effect - but the chart is not always central.