Are Gadfly plots currently composable? - ggplot2

Is there currently a way to add plot elements together in Gadfly.jl?
For example, in R if I have another function that returns a ggplot and I want to add a title to it, I'd do the following:
p <- makeMyPlot()
p + ggtitle("Now it has a title")
Is there currently a Gadfly equivalent? If not, is this on Gadfly's roadmap?

There is add_plot_element(), which can add stuff to an existing layer:
xs = [0:0.1:pi]
l = layer(x=xs, y=sin(xs))
add_plot_element(l, Guide.title("Now it has a title"))
You can then plot the layer using plot(l), and invoke either draw or display to actually show something. Further down, there's a bunch of overloads that work on a Plot directly:
p = plot(x=xs, y=sin(xs))
add_plot_element(p, Guide.title("Now it has a title"))
display(p)
I can't find either of these functions in the documentation, but fortunately the source is comprehensible enough. One of the many joys of Julia =)

Related

createjs combine 2 shapes in a mask

I have a symbol S1 with two shapes (lets say sh0 and sh1). On the stage I have an instance of another symbol mc. At run time, I will create an instance mc1 of the symbol S1. Using createjs, how can I use mc1 as a mask for mc?
I assume when you say "symbol", you mean a graphic or MovieClip in Adobe Animate. Unfortunately, you can only use a CreateJS "Shape" as a mask directly. There are a few options:
Combine the shapes into one yourself.
Combine the instructions. This is a bit dirty, but you could in theory concat the graphic instructions from one shape into another. I suspect this would have issues if the Shape instances have different x/y positions.
symbol.shape1.graphics._instructions.concat(symbol.shape2.graphics._instructions);
Cache the symbol as use it as a Mask with AlphaMaskFilter. The example in the documents should get you what you want.
var box = yourSymbol;
box.cache(0, 0, 100, 100);
var bmp = new createjs.Bitmap("path/to/image.jpg");
bmp.filters = [
new createjs.AlphaMaskFilter(box.cacheCanvas)
];
bmp.cache(0, 0, 100, 100);
The 3rd is probably your best option, but it is limiting and can be performance intensive due to the use of the filter (especially if content changes and you have to update it constantly).
Feel free to post more details on what you are working with in order to get a better recommendation.
Cheers.

Dodged Bar Plots in ggplot - Defining colour by X axis as opposed to fill

Having some issue with dodged bar charts in ggplot. Essentially the only way I can dodge them is by changing fill to another variable, but I want to colour the paired plots by what they are on the x axis.
Have included a dummy picture of what I am trying to achieve.
I'm not sure if I'm missing something obvious here.
Many thanks in advance!
One trick is to use another not so useful variable to allow the dodge to happen. In the example below, I use color to separate them, but giving all of them the same color:
X = data.frame(Year=factor(rep(c(2016,2018),3)),
Sales=runif(6),Brand=rep(c("Toyota","Skoda","Ford"),each=2))
ggplot(X,aes(x=Brand,y=Sales,fill=Brand)) +
geom_col(aes(col=Year),position="dodge",show.legend=FALSE) +
scale_color_manual(values=c("black","black")) +
geom_text(aes(label=Year,y=0.5*Sales),position=position_dodge2(1),angle=90)

Maya: Having trouble writing a script to cut a mesh into equal pieces

I want to split a mesh into sections based on a number of vertices. Essentially, I want a mesh cut into sections of 300 verts each with a remainder section of whatever is left over.
I've done this for the most part (i can get verts/faces, etc) but I'm having trouble figuring a graceful way of iterating through the extracted meshes.
I'm using polyChipOff which has no return value for the faces it chipped, so it's entirely new objects that are created that i have no handle to so i can't just continue chipping away from the previous piece as it no longer exists.
Any advice on how to go about this better?
I've thought of either iterating through all meshes in the scene for new ones (cache them at the start) or using a scriptJob to detect new objects being made. Both of those seem very hacky so was curious if anyone had advice.
You can try this method:
import maya.cmds as cmds
shape = cmds.listRelatives(p=True)
object = cmds.listRelatives(a, p=True)
selectedFace = cmds.ls(sl=True)
cmds.select(object[0] + '.f[:]', tgl=True)
unselecetedFace = cmds.ls(sl=True)
duplicated = cmds.duplicate(object, un=True)[0]
cmds.delete(duplicated, ch=True)
cmds.delete(selectedFace)
for i in range(len(unselecetedFace)):
unselecetedFace[i] = unselecetedFace[i].replace(object[0],duplicated)
cmds.delete(unselecetedFace)
cmds.select(duplicated)

In Gimp script-fu, how can you access QuickMask functionality?

In the Gimp GUI, the QuickMask is very useful for many things, but this functionality doesn't seem to be directly available through script-fu. No obvious equivalents were apparent to me in the procedure browser.
In particular, putting the (value/gray) pixels of a layer into the selection mask is the basic thing I need to do. I tried using gimp-image-get-selection to get the selection channel's id number, then gimp-edit-paste into it, but the following anchor operation caused Gimp to crash.
My other answer contains the "theoretical" way of doing it - however, the O.P. found a bug in GIMP, as of version 2.6.5, as can be seem on the comments to that answer.
I got a workaround for what the O.P. intends to do: paste the contents of a given image layer to the image selection. As denoted, edit-copy -> edit-paste on the selection drawable triggers a program crash.
The workaround is to create a new image channel with the desired contents, through the copy and paste method, and then use gimp-selection-load to make the selection equal the channel contents:
The functions that need to be called are thus (I won't paste scheme code, as I am not proficient in all the parenthesis - I did the tests using the Python console in GIMP):
>>> img = gimp.image_list()[0]
>>> ch = pdb.gimp_channel_new(img, img.width, img.height, "bla", 0, (0,0,0))
>>> ch
<gimp.Channel 'bla'>
>>> pdb.gimp_edit_copy(img.layers[0])
1
>>> pdb.gimp_image_add_channel(img, ch, 0)
>>> fl = pdb.gimp_edit_paste(ch, 0)
> >> fl
<gimp.Layer 'Pasted Layer'>
>>> pdb.gimp_floating_sel_anchor(fl)
>>> pdb.gimp_selection_load(ch)
Using QuickMask through the User interface is exactly equivalent to draw on the Selection, treating the selection as a drawable object.
So, to use the equivalent of "quickmask" on script-fu all one needs to is to retrieve the Selection as a drawable and pass that as a parameter to the calls that will modify it -
And to get the selection, one just have to call 'gimp-image-get-selection'

Need advice on wordy naming of methods

I'm writing an API for creating geometric shapes, and I'm running into some difficulties naming my methods.
Let's take a simple case: Creating a circle. Most of us might be familiar with a method like graphics.drawEllipse(x, y, w, h). To draw a circle, you need to know the top left coordinate, and the width and height of the circle.
My API is intended to make it easy for a developer to draw shapes using a variety of information, without doing a lot of math - which is trivial for circles, but more complicated for other shapes. For example, you should also be able to draw a circle given its center coordinates and radius, or the top left and bottom right coordinates.
So I have a Circle class with factory methods like:
Circle.createWithCenterAndRadius(cx, cy, r)
Circle.createWithBoundingBox(x1, y1, x2, y2)
Circle.createWithWidthAndHeight(x, y, w, h)
I feel like there might be a "code smell" here, but I'm not sure. On the one hand, these factory methods are necessarily descriptive. On the other hand, I can forsee these method names getting out of control. For example, how would I name a Triangle factory method that creates a triangle given a point, the length of one side, an angle, and the length of another side? Triangle.createWithPointSideAngleAndSide(x, y, side1, angle, side2)? Is that just evil?
If you were to use this API, would method names like this be okay to you? Do you have advice on how I can make the method names more sane?
You might change your circle methods to
Circle.FromCenterAndRadius(...)
Circle.FromBoundingBox(...)
Circle.FromWidthAndHeight(...)
It implies that you're creating circles from their different representations in a kind of concise way...
It is ok in any language that doesn't support named parameters. If the language supports named parameters, I like more the short Create and just have obvious parameters names.
For a language with named parameters, you would:
Circle.Create(
centerX = cx,
centerY = cy,
radius = r
);
Another more involved option, would be a fluent interface like (but that is probably too much):
circleBuilder.Center(cx,cy).Radius(r)
circleBuilder.Center(x,y).Width(w).Height(y)
circleBuilder.BoundWith().Left(x1,y1).Right(x2,y2)
Center returns an instance of an intermediate class that only allows Radius or Width. And BoundWith returns one that only allows Left.
I think there is nothing wrong with your descriptive methods - they are the compact and describe exactly what's going on. The users of the library will have no doubt about the function of your methods, neither the maintanance programmers.
You could also apply some design pattern here if you are really worried about exposing a large number of factory methods - like having factory methods with property classes. You could have a CircleProperties class with properties like CenterX, CenterY, Radius, (bool)UseCenterX, (bool)UseCenterY etc and then you pass this to the public factory method which will figure out which (private) factory method to use.
Assuming C#:
var circleProperties = new CircleProperties()
{
CenterX = 10,
CenterY = -5,
Radius = 8,
UseCenterX = true,
UseCenterY = true,
UseCenterRadius = true
};
var circle = Circle.Create(circleProperties);
My first instinct is to have more types, which would allow for more intuitive method overloading.
// instead of Circle.createWithCenterAndRadius(cx, cy, r)
Circle.create( new Point(cx,xy), r);
// instead of Circle.createWithBoundingBox(x1, y1, x2, y2)
Circle.create( new Point(x1,y1), new Point(x1,y1) );
// or even...
Circle.create( new Box(p1,p2));
// instead of Circle.createWithWidthAndHeight(x, y, w, h)
Circle.create( new Point(x,y), w, h);
As well as Point, you could define Distance (which would allow for different units)
If this style suits you, consider why you need a factory method instead of a constructor.
Circle c = new Circle(new Point(cx,xy), r);
For languages that don't support named parameters, would it be cleaner to make the method name something very simple like Circle.create and then just add an additional input flag string (like "center" or "bounding") that indicated how the input values should be interpreted for cases that are hard to discriminate based only on input variable number and type? Drawbacks to this would be that it requires extra logic inside of the method to handle different types of input arguments and also requires that the user remember the flag options.
I would have methods CreateTriangle and have the overloads show the different pieces of information required.
E.g.
Circle.CreateCircle(cx, cy, r)
Circle.CreateCircle(point1, point2)
Circle.CreateCircle(point, width, height)
Yes, this is more of a meta-answer, but I suggest you take a peek at how naming is done in Apple's Cocoa.
Your instinct is correct--the entire pattern of creating things this way is--iffy.
Unless these are used just once or twice, they are going to become pretty messy. If you were creating a shape with 5 circles and 3 triangles, it would be a mess.
Anything beyond a trivial example would probably be best done with some kind of data-driven implementation.
Towards those ends, having it take a string, hash or XML to define your shapes might be extremely useful.
But it all depends on how you expect them to be used.
I have the same kind of issues with creating Swing controls in Java. You end up with line after line of "new Button()" followed by a bunch of .set property calls as well as a line of code to copy the value to an object (or add a listener), and a line to reset the value..
That kind of boilerplate should never happen in code, so I usually try to find a way to drive it with data, binding the controls to objects dynamically--and towards that end, a descriptive string-based language would be very helpful.
I know, I know. This sounds completely crazy for you C/C++/Java people, but the examples given in the question and in all those answers clearly demonstrate what a bad, bad convention CamelCaseNaming really is.
Let's take another look at the original example:
Circle.createWithCenterAndRadius(cx, cy, r)
Circle.createWithBoundingBox(x1, y1, x2, y2)
Circle.createWithWidthAndHeight(x, y, w, h)
And now let's get rid of that camel case notation
Circle.create_with_center_and_radius(cx, cy, r)
Circle.create_with_bounding_box(x1, y1, x2, y2)
Circle.create_with_width_and_height(x, y, w, h)
This may seem terribly unfamilar, but be honest: which version is easier to read?