interpolation

问题 Is there a library module or other straightforward way to implement multivariate spline interpolation in python? Specifically, I have a set of scalar data on a regularly-spaced three-dimensional grid which I need to interpolate at a small number of points scattered throughout the domain. For two dimensions, I have been using scipy.interpolate.RectBivariateSpline, and I\'m essentially looking for an extension of that to three-dimensional data. The N-dimensional interpolation routines I have

问题 I\'ve found some methods to enlarge an image but there is no solution to shrink an image. I\'m currently using the nearest neighbor method. How could I do this with bilinear interpolation without using the imresize function in MATLAB? 回答1: In your comments, you mentioned you wanted to resize an image using bilinear interpolation. Bear in mind that the bilinear interpolation algorithm is size independent. You can very well use the same algorithm for enlarging an image as well as shrinking an

问题 Could someone please explain what\'s behind the following behavior? Say we have an Angular 2 component that has a _model object. Then in the template we have this: <form> <input type=\"text\" class=\"form-control\" required [(ngModel)]=\"_model.firstName\" ngControl=\"test2\" #myInput > <br>Class: {{myInput?.className}} </form> The _model is available from the beginning being created from scratch in ngOnInit() . The input field is properly populated with the _model.firstName variable and the

问题 I was using one of the proposed algorithms out there but the results are very bad. I implemented the wiki algorithm in Java (code below). x(0) is points.get(0) , y(0) is values[points.get(0)] , α is alfa and μ is mi . The rest is the same as in the wiki pseudocode. public void createSpline(double[] values, ArrayList<Integer> points){ a = new double[points.size()+1]; for (int i=0; i <points.size();i++) { a[i] = values[points.get(i)]; } b = new double[points.size()]; d = new double[points.size(

问题 I am trying to write my own function for scaling up an input image by using the Nearest-neighbor interpolation algorithm. The bad part is I am able to see how it works but cannot find the algorithm itself. I will be grateful for any help. Here\'s what I tried for scaling up the input image by a factor of 2: function output = nearest(input) [x,y]=size(input); output = repmat(uint8(0),x*2,y*2); [newwidth,newheight]=size(output); for i=1:y for j=1:x xloc = round ((j * (newwidth+1)) / (x+1));

问题 I am trying to rotate an image with Matlab without using imrotate function. I actually made it by using transformation matrix.But it is not good enough.The problem is, the rotated image is \"sliding\".Let me tell you with pictures. This is my image which I want to rotate: But when I rotate it ,for example 45 degrees, it becomes this: I am asking why this is happening.Here is my code,is there any mathematical or programming mistakes about it? image=torso; %image padding [Rows, Cols] = size

问题 Please have a look at the following example: http://jsfiddle.net/MLGr4/47/ var canvas = document.getElementById(\"canvas\"); var ctx = canvas.getContext(\"2d\"); img = new Image(); img.onload = function(){ canvas.width = 400; canvas.height = 150; ctx.drawImage(img, 0, 0, img.width, img.height, 0, 0, 400, 150); } img.src = \"http://openwalls.com/image/1734/colored_lines_on_blue_background_1920x1200.jpg\"; As you see, the image is not anti-aliased although it is said that drawImage applies anti