coordinates

问题 I make a square around/below a given point with given width (w) and length (l) like shown below But now I have to induce the direction of the point (or heading so to say). I want to create a rectangle directed towards that direction like shown below. I have never worked with headings before, if anyone can point me in the right directions, that would be helpful. -----------------EDIT--------------- Thank you @MBo & @HansHirse, I implemented as suggested by your people. for simplicity, I chose

问题 I'm trying to set the back color of each TextBox that is within the rectangle defined between a MouseDown and MouseUp event, where the MouseUp event takes place to the right of and below the MouseDown event. I capture the Points this way: static readonly Color PSEUDO_HIGHLIGHT_COLOR = Color.Gainsboro; private Point selectionStart; private Point selectionEnd; . . . private void flowLayoutPanelGreatGooglyMoogly_MouseDown(object sender, MouseEventArgs e) { if (e.Button == MouseButtons.Left) {

问题 I have the following dataframe: d = {'Postcode': ['M3A','M4A','M5A','M6A','M9A','M1B'], 'Borough': ['North York', 'Downtown Toronto', 'Etobicoke', 'Scarborough', 'East York', 'York'], 'Neighbourhood': ['Parkwoods', 'Victoria Village', 'Harbourfront', 'Regent Park', 'Lawrence Heights', 'Lawrence Manor']} post_df = pd.DataFrame(data = d) Wich yields something like: Postcode Borough Neighbourhood 0 M3A North York Parkwoods 1 M4A Downtown Toronto Victoria Village 2 M5A Etobicoke Harbourfront 3

问题 I am attempting to be create a polygon table of hexagons, with a name for each hexagon (e.g. Hex1, Hex2, etc...) and join the polygon table to a table of records that have x and y coordinates if the coordinates fall within a polygon. Creating the hex table with the code below, when ran in isolation, seems to be working (except for some of my numbers being off, creating some overlap) DECLARE @Hex TABLE --Create table to old hexagons (PointGeom geometry, Hex varchar(6)) INSERT INTO @Hex -

问题 I am working on an iPhone app where I need to find some coordinates at some distance from a given point. The user touches the map and I get coordinates at the touch. Now I have to find some coordinates which are about 5 km away towards east and another one about 5km down to south. I have searched the web but could not find any algorithm for it. I am not sure this is correct place for this question or whether I need to find some other section where I can find questions related to maths. 回答1:

问题 I am having trouble setting a orthographical projection matrix of dimensions 4x2 with (0,0) being in the center, (-2, -1) being at the bottom left corner, and (2, 1) being at the top right corner. I use glutInitWindowSize(600, 300); to initialize the window size. In my reshape function, I use glViewport(0, 0, w, h); to set the viewport. Also in my reshape function, I use gluOrtho2D(-(float)w/h, (float)w/h, -2.0, 2.0); to set the ortho. However, when I move my mouse around to see the world

问题 I am new to R and I have a simple problem (by my opinion) but I haven't found a solution so far. I have a (long) set of 2D (x,y) coordinates - just points in 2D space, like this: ID x y 1 1758.56 1179.26 2 775.67 1197.14 3 296.99 1211.13 4 774.72 1223.66 5 805.41 1235.51 6 440.67 1247.59 7 1302.02 1247.93 8 1450.4 1259.13 9 664.99 1265.9 10 2781.05 1291.12 etc..... How do I filter points (rows in the table) that are in certain area (of any shape!)? How to filter dots that are within a subset

问题 I wanna generate a random triangle with coordinates, which shows the arcs of each corner in actionscript 2.0 with flash 8.0. 回答1: This looks a lot like your previous question (also a lot like this other question), but here goes: import flash.geom.Point; function randomPoint():Point { //return a random point on the stage var p:Point = new Point(Math.floor(Math.random()*(Stage.width-300)), Math.floor(Math.random()*Stage.height)); return p; } function drawTriangle(mc:MovieClip, q1:Point, q2

问题 In openCV(C++) I have an image IMG and I'd like to extract the values of each pixel at positions store in coor . Is it possible to get this pixel values in an efficient way? Is a foor loop (using .at(i,j) ) efficient ?Is there a built-in function for doing this? This is my code: cv::Mat IMG = cv::imread("image.png",CV_LOAD_IMAGE_GRAYSCALE); cv::Mat coor = (cv::Mat_<float>(3,2) << 1, 0, 0, 1, 2, 2); // search coordinates cv::Mat pixel_values; // and I'd like to do something like this: //This

问题 Hi I'm totaly new to android, I'm looking for a very very very simple thing that in every possible dev env is straight forward, except apparently android. how the hell do I set X and Y for every UI object that I wanna place there. For example in xml i have LinearView or RelativeView and in them I have Button, I'm looking for a way to set this button position on the screen using Y and Y, should be pretty straight forward thingy, I mean in iOS dev you just do CGRectMake(x,y,width,height) and