point

Possible Duplicate: What is a simple example of floating point/rounding error? When I execute the following Lua code: a = 5.6 b = 14 * 0.4 c = 11.2 / 2 d = 28 * 0.2 print( a == b ) print( a == c ) print( a == d ) print( b == c ) print( b == d ) print( c == d ) I get the following results: false true false false true false Can someone explain why 14 * 0.4 and 28 * 0.2 are not equal to 5.6? Thanks You are dealing with the natural imprecision of binary floating point numbers. Your number a might be 5.5999999999999996 and your result b might be 5.6000000000000005, which are not equal. In fact,

I am attempting to display the plot values of different points on my QCustomPlot in which I have a Line style of lsLine . I know i could set a mouse over signal on the QCustomPlot but that wont really help since I just need to be informed when the mouse is over my plotted line.My question is is there any way to find out if the mouse is over my scatter point. Is there a signal i could connect to that would tell me when the mouse is over a scatter point ? Reimplement QCustomPlot::mouseMoveEvent or connect to QCustomPlot::mouseMove . Then use axes' coordToPixel to translate (cursor) pixel coords

I would like to find a fast algorithm in order to find the x closest points to a given point on a plane. We are actually dealing with not too many points (between 1,000 and 100,000), but I need the x closest points for every of these points. (where x usually will be between 5 and 20.) I need to write it in C#. A bit more context about the use case: These points are coordinates on a map. (I know, this means we are not exactly talking about a plane, but I hope to avoid dealing with projection issues.) In the end points that have many other points close to them should be displayed in red, points

Awhile back I asked a question to see if I was able to find a pair of specific points in a path; however, this time I want to know if there is a way to know all points in a path? (I couldn't find a method that did so, which is unfortunate because Java provides a way to do this, just not Android?) The reason I ask this is because I have multiple geometric graphs and I want to compare the points to see where they intersect. I appreciate any helpful responses If you have created a Path that means that in some point of your code, you know the exact (Geo)point. Why don't you put this point(s) on a

I have put an UIImageView control on my view with IB. The size of the control is just something I decided upon, pretty random size really What I want to do is the control to resize automatically whenever I set the image property to a new image. I want it to actually resize to the size of the image. Can it be done automatically ? without any code intervention ? If not - what will the best approach be in this case ? What happens today is strange. I load images into the ImageView and I see the images getting displayed properly even though the size of the ImageView is not changed. This interferes

In some simulation program we generate object surfaces in terms of points, each point has 3D coordinates and the vector that represents the normal to the surface at that point. For visualization purposes we would like to generate a mesh composed of triangles; each three close points form one triangle with its normal. Then we can send this information to some standard visualization programs that render the surface like VMD (Visual Molecular Dynamics). We wonder which is the fastest/available algorithm for doing this. Take a look at Jonathan Shewchuk 's work, especially on his (together with his

I have a map made up of rows and columns of hexagons This isn't an actual image of the hex-map I am using, but uses the same size and shape hexagons I need to be able to tell which one the mouse is over when the user clicks, Each Hexagon is represented by an instance of a "Tile" class, however this doesn't hold any location specific data, or even a polygon, so basically the only way to tell where a particular hexagon is, is to know it's position in the 2D array. I have used a square grid before, and it was relatively easy to figure out which square was selected, because pixels are also square,

Is there any way to get the + operator to work for the Point object? Take, for example, this tiny snippet: this.cm1.Show((MouseEventArgs)e.Location+this.i_rendered.Location); You see, I try to add two points to eachother. It just does not work (which was expected). I'd love to get this working. Any ideas? Cody Gray It's not going to happen the way you expect. The only overload that the Point structure provides for the + (addition) operator is one that translates the coordinates of the Point by a Size . There's no way to add two Point structures together, and I'm not even sure what that would