spline

问题 I've been able to apply a smooth animation to my sprite and control it using the accelerometer. My sprite is fixed to move left and right along the x-aixs. From here, I need to figure out how to create a vertical infinite wavy line for the sprite to attempt to trace. the aim of my game is for the user to control the sprite's left/right movement with the accelerometer in an attempt to trace the never ending wavy line as best they can, whilst the sprite and camera both move in a vertical

问题 I tried the following: spline= interpolate.InterpolatedUnivariateSpline(X, Y, k=3) coefs= spline.get_coeffs() With five values in each of X and Y , I ended up with coefs also having five values. Given that five data points implies four spline sections, and that a cubic polynomial has four coefficients, I would have expected to get four times four= 16 coefficients. Does anyone know how to interpret the values that are returned by the get_coeffs method? Is there any place where this is

问题 So my goal is to draw a spline similar to this one (where the line goes through each point): But the spline loops around (from the end point 2 back to the start point): I tried changing the "continuous" boolean in the catmullromspline, but that resulted in only a dot being drawn in the center of the screen. I also ended the line drawing when it hit the last point, but the result was ugly because the line was still curving at the start and end points. I looked everywhere in the source code,

问题 So my goal is to draw a spline similar to this one (where the line goes through each point): But the spline loops around (from the end point 2 back to the start point): I tried changing the "continuous" boolean in the catmullromspline, but that resulted in only a dot being drawn in the center of the screen. I also ended the line drawing when it hit the last point, but the result was ugly because the line was still curving at the start and end points. I looked everywhere in the source code,

问题 I realise that there are posts on the topic of B-Splines on this board but those have actually made me more confused so I thought someone might be able to help me. I have simulated data for x-values ranging from 0 to 1. I'd like to fit to my data a cubic spline ( degree = 3 ) with knots at 0, 0.1, 0.2, ... , 0.9, 1. I'd also like to use the B-Spline basis and OLS for parameter estimation (I'm not looking for penalised splines). I think I need the bs function from the spline package but I'm

问题 I need to discretise a 3rd order Bezier curve with points equally distributed along the curve. The curve is defined by four points p0, p1, p2, p3 and a generic point p(t) with 0 < t < 1 is given by: point_t = (1 - t) * (1 - t) * (1 - t) * p0 + 3 * (1 - t) * (1 - t) * t * p1 + 3 * (1 - t) * t * t * p2 + t * t * t * p3; My first idea was to discretise t = 0, t_1, ... t_n, ..., 1 This doesn't work as, in general, we don't end up with a uniform distance between the discretised points. To sum up,

问题 I am trying to find a python package that would give an option to fit natural smoothing splines with user selectable smoothing factor. Is there an implementation for that? If not, how would you use what is available to implement it yourself? By natural spline I mean that there should be a condition that the second derivative of the fitted function at the endpoints is zero (linear). By smoothing spline I mean that the spline should not be 'interpolating' (passing through all the datapoints). I

问题 It's been a while since I did any maths* of this kind, so perhaps someone can answer this for me. I don't think this question is exactly what I want, because I am trying to find intersections for precise x values. So I have a spline which goes from X,Y to XX,YY, with control points at each end. I think I would be correct in saying it will be a quadratic curve (the curve will not cross itself). I plan on using the path routines from the given graphics library (currently thinking HTML5 canvas)

问题 This question is in the context where I have a lot Model types, each of the same class, but the amount of data for each Model is small and I want to spline to get a fuller dataset. I'm hoping to find a way to do this without having to individually spline every Model once at a time. So I have the following df: mydf<- data.frame(c("a","a","b","b","c","c"),c("e","e","e","e","e","e") ,as.numeric(c(1,2,3,10,20,30)), as.numeric(c(5,10,20,20,15,10))) Give some names: colnames(mydf)<-c("Model",

问题 I have a 3D-object that is navigating the CatmullRom spline. The code I'm using is taken from Xoppa's answer here: Xoppa's answer There are 2 ways of aligning object along thre spline. I tried both of them. And have weird results with both. Option 1 (it mostly OK but have a weird rotations occuring...see image below): Option 2 (removes issue from Option 1 but everything else is not okay..see image below ): My spline: pointsArray = new Vector3[21]; pointsArray[0] = new Vector3(-5, -2, 2);