X axis glitch Fl_charts - flutter

I have data in the form of [DateTime, num]. I have converted the DateTime object into a string and used it as a x-axis label. I am getting this glitch now. Is there a property which I need to change to fix this?
As you can see, there is a repetition of the x axis labels at either end. I am using Fl_Chart library. If you require my current code I can attach it.

fl_chart uses the interval you provide to determine which points should have labels for, however, it also creates a label for 0 and maxX. You can fix it by adding
if (value % (xAxisInterval?.ceil() ?? 1) == 0) {
//return label
}else{
return SideTitleWidget(
axisSide: meta.axisSide,
child: Container(),
);
}
to your getTitlesWidget function. Where xAxisInterval is the value you passed into your SideTitles object for interval for the xAxis.

Related

Hi I want to display a positive negative value graph in apex chart , I want 2 individual color like green for positive and red for negative

How to display 2 bar color, attached the image.
I tried giving a loop then if the condition inside the loop but only for the first value is the color set not for the remaining values (apex chart).
colors: [function() {
for (var i in chartdata ) {
if(chartdata[i]>1){
console.log("positive")
// setPostiveColor("#0000FF")
return '#7E36AF'
} else if(chartdata[i]<0){
console.log("negative",chartdata[i])
return '#D9534F'
}
}

how can i replace the original value with another

i have the following code
Listener(
onPointerMove: (detail){
print(detail.position);
}
)
now by default detail.position will give the following
Offest(dy,dx);
now after many test i noticed the max value of dy equal MediaQuery.of(context).size.height
and the same with dx the max value equal MediaQuery.of(context).size.width
lets assume that my MediaQuery.of(context).size.height equal 800 in double, and i wrap my scaffold into Listener widget so if i touch any point (lets say at the bottom at the last point in screen ) so of course i will outputs 800 .
Question what if i want replace the max value with other value lets say from 800 to 1000 ??
in other word when i repeat the same touch process so it will outputs 1000 .
NOTE : i know it is impossible to replace it but i mean I want the output calculations to come based on a maximum value of the value I set and not MediaQuery.of(context).size.height so There is no problem if the value remains the same .
in the fact other value come from image height from server so it is not fixed always it might be even less than original value
i need it the same with width too .
It's purely a math matter
How can i handle with it ?

Is there a way to get the ECharts series symbol to be passed in as the marker in the tooltip

I've got an ECharts chart that has multiple line series and a scatter series that represents events. For the line series, we left the symbol at the default, but for the event scatter series we set the symbol to 'diamond'. These symbols show up on the chart & in the series legend as expected. However, the tooltip always shows a 10 pixel dot for the marker. The color however is picked up from the series (and even from the visualMap config!). My initial assumption had been that the symbol would also be picked up from the series. In our case we wanted to use a function for tooltip.formatter and even in that function we couldn't figure out how to access and swap in the series symbol for the marker. We ended up working around it by just custom styling our own html to plug in for the marker that matched the diamond symbol pretty well.
So the open questions are:
Is there a way to have the tooltip marker pick up the symbol from the series?
If not, is this a bug? I'm happy to put in an issue on the project but I don't want to do that until I understand a bit more.
Here's some code to illustrate what we had to do to get the diamond in there in case it helps the discussion or if others want to leverage this workaround:
formatTooltip(args){
let time = DateTime.fromISO(args[0].data[0], { zone: this.user.timeZone })
let tooltip = `<div><b>${time.toFormat(TOOLTIP_FORMAT)}</b></div>`
args.forEach(({ marker, seriesName, value }) => {
if (seriesName === 'Events'){
let myMarker = `<span style="display:inline-block;margin-right:4px;width:10px;height:10px;background:${value[4]};transform:rotate(45deg);"></span>`
tooltip += `<div>${myMarker} ${value[3] ? value[3]: ''}</div>`
} else {
value = value || [0, 0]
tooltip += `<div>${marker} ${seriesName}: ${value[1]}</div>`
}
})
return tooltip
},

Physicsjs Screen wrap

I am currently having a bit of trouble making objects in my world wrap. It sort of works, but very often objets appear to get stuck on the boundaries. My wrap code is as follows:
// Wrap our position if we are outside of the world bounds
if (this.state.pos.get(0) > 860) {
this.state.pos.set(0, this.state.pos.get(1));
}
else if (this.state.pos.get(0) < 0) {
this.state.pos.set(860, this.state.pos.get(1));
}
if (this.state.pos.get(1) > 640) {
this.state.pos.set(this.state.pos.get(0), 0);
}
else if (this.state.pos.get(1) < 0) {
this.state.pos.set(this.state.pos.get(0), 640);
}
Is there a better way of doing this? Should I use a translation on the object's position vector rather than simply setting it?
Without a jsfiddle it's a bit hard to diagnose, however this might be due to the this.state.old.pos not being set too. If the position (only) is set, then the velocity will be calculated as the difference between the current and the previous positions (in accordance with verlet integration). In that case, you're implicitly giving the body a huge velocity.
I'd recommend adding/subtracting an amount rather than setting, then you can do the same with the old position.
Here's a working example: http://labs.minutelabs.io/Relativistic-Space-Sheep/
With the relevant line of code: https://github.com/minutelabsio/Relativistic-Space-Sheep/blob/master/library/js/mediators/boilerplate.js#L743

Line chart/graph with an irregular threshold field

Looking to create a bar chart with an irregular, colored threshold field in the background, so that each data point has its own individual set of min/max thresholds, which ultimately would look something like this: http://dcalvitti.webs.com/plant/SAMPLE.png
Looked at D3 examples like this one: http://bl.ocks.org/mbostock/4062844
Can the latter example be manipulated to look more like the image I created?
Thanks in advance..
The graph shown in your sample image is actually much easier than the linked example; for that, you don't need to create a clipping path and you don't need to draw the line twice with two different colours.
For drawing the coloured background, use an area-path generator, created with d3.svg.area(). Set the y0 accessor function to be extract your minimum value for each point in your data array, and the y1 accessor function to extract the maximum value.
Then draw the line overtop as a normal line graph with a d3.svg.line() path generator.
Working example, adapted from the fiddles in the comments: http://jsfiddle.net/h45CD/12/
(Note: I commented out half the dataset, since the "year" values were repeated, not sure what that was supposed to represent.)
Key code:
// Define the value line path generator
var line = d3.svg.line()
.x( function(d) { return x(d.year); } )
.y( function(d) { return y(d.temp); } );
// Define the area path generator
var area = d3.svg.area()
.x( function(d) { return x(d.year); } )
.y0( function(d) { return y(d.min); } )
.y1( function(d) { return y(d.max); } );
/* ... */
// Add the background area showing the historic range
svg.append("path")
.datum(data)
.attr("class", "historicRange")
.attr("d", area);
// Add the value line
svg.append("path")
.datum(data)
.attr("class", "dataline")
.attr("d", line);
Edit based on comments
If you do want a line that changes colour depending on historic values, as opposed to a line drawn overtop of a background range, the most straight-forward solution is probably to create a <pattern> element consisting of the different coloured regions, and use this to stroke the value line.
You'll want to familiarize yourself with the different options for the pattern element. This MDN tutorial has a good intro, or you could dive into the full W3 specs.
For this situation, we want the pattern to be sized and positioned relative to the coordinate system used for drawing the line, regardless of the size or shape of the line itself. That means we will be setting both the patternUnits and the patternContentUnits to be userSpaceOnUse. The height and width of the pattern will be the height and width of the plotting area.
Within the pattern we will draw the area that represents the max-min range, but we also need to draw separate areas, with different colours, for values above the max and values below the min. We can use the same area generator for each, but need to change the y0/y1 accessor functions each time.
Key code:
// Add the pattern showing the historic range
var pattern = defs.append("pattern")
.datum(data) //add the data to the <pattern> element
//so it will be inherited by each <path> we append
.attr({
"patternUnits":"userSpaceOnUse",
"patternContentUnits":"userSpaceOnUse",
"width": width,
"height": height
})
.attr("id", "strokePattern");
pattern.append("path")
.attr("class", "historicRange between")
.attr("d", area);
pattern.append("path")
.attr("class", "historicRange above")
.attr("d", area.y1( 0 )
.y0( function(d){return y(d.max);} )
);
pattern.append("path")
.attr("class", "historicRange below")
.attr("d", area.y1( function(d){return y(d.min);} )
.y0( height )
);
// Add the value line
plot.append("path")
.datum(data)
.attr("class", "dataline")
.attr("d", line)
.style("stroke", "url(#strokePattern)");
Working example: http://jsfiddle.net/h45CD/14/
I'm including a web page link with charts authored by myself based on AMCharts and with the help of that web site's founder. Contains several examples of the above question and more..
http://dcalvitti.webs.com/SAMPLE/NEWWEBINDEX.html
The charts provided are still being worked on. For example, AMcharts does have a function that clips the color of a line above/below a certain value which I didn't know about, so there is still work to be done. I spent many weeks on the charts and thought I'd share. I'm sure someone will find something new here down the road...