angle

I imagine that this is a simple question, but I'm getting some strange results with my current code and I don't have the math background to fully understand why. My goal is simple, as stated in the title: I just want to find the point at some distance and angle from a center point. My current code: Point centerPoint = new Point ( 0, 0 ); Point result = new Point ( 0, 0 ); double angle = 0.5; //between 0 and 2 * PI, angle is in radians int distance = 1000; result.Y = centerPoint.Y + (int)Math.Round( distance * Math.Sin( angle ) ); result.X = centerPoint.X + (int)Math.Round( distance * Math.Cos(

I want to find out the clockwise angle between 2 vectors(2D, 3D). The clasic way with the dot product gives me the inner angle(0-180 degrees) and I need to use some if statements to determine if the result is the angle I need or its complement. Do you know a direct way of computing clockwise angle? 2D case Just like the dot product is proportional to the cosine of the angle, the determinant is proprortional to its sine. So you can compute the angle like this: dot = x1*x2 + y1*y2 # dot product between [x1, y1] and [x2, y2] det = x1*y2 - y1*x2 # determinant angle = atan2(det, dot) # atan2(y, x)

Given 2 angles in the range -PI -> PI around a coordinate, what is the value of the smallest of the 2 angles between them? Taking into account that the difference between PI and -PI is not 2 PI but zero. Example: Imagine a circle, with 2 lines coming out from the center, there are 2 angles between those lines, the angle they make on the inside aka the smaller angle , and the angle they make on the outside, aka the bigger angle. Both angles when added up make a full circle. Given that each angle can fit within a certain range, what is the smaller angles value, taking into account the rollover

How would you find the signed angle theta from vector a to b? And yes, I know that theta = arccos((a.b)/(|a||b|)). However, this does not contain a sign (i.e. it doesn't distinguish between a clockwise or counterclockwise rotation). I need something that can tell me the minimum angle to rotate from a to b. A positive sign indicates a rotation from +x-axis towards +y-axis. Conversely, a negative sign indicates a rotation from +x-axis towards -y-axis. assert angle((1,0),(0,1)) == pi/2. assert angle((0,1),(1,0)) == -pi/2. If you have an atan2() function in your math library of choice: signed

I want to Rotate Image according to a specific angle in android ,some thing like a compass... I have this code...it works on drawPath() but i want to replace the path and the Drawing thing with image.. I tried to create a bitmap image ,DrawBitmapImage , but the image does not Rotate like the path..Any Help PLease? public void draw(Canvas canvas) { double angle = calculateAngle(currentLongitude, currentLatitude, targetLongitude, targetLatitude); //Correction; angle-=90; //Correction for azimuth angle-=azimuth; if((getContext() instanceof Activity) && ((Activity)getContext()).getWindowManager()

I need to determine the angle(s) between two n-dimensional vectors in Python. For example, the input can be two lists like the following: [1,2,3,4] and [6,7,8,9] . Alex Martelli import math def dotproduct(v1, v2): return sum((a*b) for a, b in zip(v1, v2)) def length(v): return math.sqrt(dotproduct(v, v)) def angle(v1, v2): return math.acos(dotproduct(v1, v2) / (length(v1) * length(v2))) Note : this will fail when the vectors have either the same or the opposite direction. The correct implementation is here: https://stackoverflow.com/a/13849249/71522 Note : all of the other answers here will