matrix

LeetCode_329矩阵中的最长递增路径

由 穿精又带淫゛_ 提交于 2020-01-15 14:54:47
给定一个整数矩阵，找出最长递增路径的长度。 对于每个单元格，你可以往上，下，左，右四个方向移动。 你不能在对角线方向上移动或移动到边界外（即不允许环绕）。 class Solution { public int longestIncreasingPath ( int [ ] [ ] matrix ) { int row = matrix . length ; if ( row < 1 ) return 0 ; int col = matrix [ 0 ] . length ; if ( col < 1 ) return 0 ; int res = 0 ; Map < String , Integer > map = new HashMap < String , Integer > ( ) ; for ( int i = 0 ; i < row ; i ++ ) { for ( int j = 0 ; j < col ; j ++ ) { int value = dfs ( i , j , matrix , map ) ; res = Math . max ( res , value ) ; } } return res ; } public int dfs ( int i , int j , int [ ] [ ] matrix , Map < String , Integer >

c++ bad allocation when matrix size exceeds a certain limit with Eigen matrix type

由 回眸只為那壹抹淺笑 提交于 2020-01-15 13:12:58
问题 In a c++ dynamic library I solve a least square problem using the Eigen Library. This Dll is called inside a python software where the problem configuration is settled. In a small sized problem the code works properly and returns the correct solution. If the number of points increases then the library throws std::bad_alloc . More precisely, The code which creates the error simplified to its most is try { matrixA = new Eigen::MatrixXd(sizeX,NvalidBtuple); // initialize A for (int i=0;i<sizeX;+

Monogame XNA transform matrix for a single object?

由 落爺英雄遲暮 提交于 2020-01-15 12:38:12
问题 I have read a few tutorials explaining transform matrices for XNA/Monogame. The problem is that these matrices are applied to SpriteBatch.Begin(...matrix); This means that all Draw code will be transformed. How do I apply a transformation matrix to a single drawable object? In my case I want to transform a scrolling background so that it automatically wraps. SpriteBatch.Draw(.. this has no transform matrix parameter?); 回答1: If you want to use a specific spritebatch begin call for some drawing

OpenMP parallelization (Block Matrix Mult)

由 僤鯓⒐⒋嵵緔 提交于 2020-01-15 11:11:07
问题 I'm attempting to implement block matrix multiplication and making it more parallelized. This is my code : int i,j,jj,k,kk; float sum; int en = 4 * (2048/4); #pragma omp parallel for collapse(2) for(i=0;i<2048;i++) { for(j=0;j<2048;j++) { C[i][j]=0; } } for (kk=0;kk<en;kk+=4) { for(jj=0;jj<en;jj+=4) { for(i=0;i<2048;i++) { for(j=jj;j<jj+4;j++) { sum = C[i][j]; for(k=kk;k<kk+4;k++) { sum+=A[i][k]*B[k][j]; } C[i][j] = sum; } } } } I've been playing around with OpenMP but still have had no luck

Why doesn't this viewing/projection transform work?

由 六眼飞鱼酱① 提交于 2020-01-15 10:23:12
问题 I'm trying to understand OpenGL's basic matrix transformation logic better. This is 2D code copied from a textbook and modified to handle 3D; it "sort of works", but the final result is visually different when I do the matrix multiplication myself vs. using glMultMatrix. The lines marked 'XXX' allow flipping between 'my multiplication' and 'OpenGL multiplication'. I tried some obvious things (eg. row vs. column major, order of transforms, etc.) If anyone can illuminate me as to what I'm doing

Why doesn't this viewing/projection transform work?

由 烂漫一生 提交于 2020-01-15 10:23:10
问题 I'm trying to understand OpenGL's basic matrix transformation logic better. This is 2D code copied from a textbook and modified to handle 3D; it "sort of works", but the final result is visually different when I do the matrix multiplication myself vs. using glMultMatrix. The lines marked 'XXX' allow flipping between 'my multiplication' and 'OpenGL multiplication'. I tried some obvious things (eg. row vs. column major, order of transforms, etc.) If anyone can illuminate me as to what I'm doing

Why doesn't this viewing/projection transform work?

由 拥有回忆 提交于 2020-01-15 10:23:09
问题 I'm trying to understand OpenGL's basic matrix transformation logic better. This is 2D code copied from a textbook and modified to handle 3D; it "sort of works", but the final result is visually different when I do the matrix multiplication myself vs. using glMultMatrix. The lines marked 'XXX' allow flipping between 'my multiplication' and 'OpenGL multiplication'. I tried some obvious things (eg. row vs. column major, order of transforms, etc.) If anyone can illuminate me as to what I'm doing

How to assign a set of numbers randomly to a matrix in R

由 柔情痞子 提交于 2020-01-15 09:30:15
问题 I need to assign fixed numbers, let's say "x", "y", "z", etc., randomly to a matrix. How can I do that? I did search about it but they all explained how to make a matrix with random numbers. But my numbers aren't random. I know what numbers I want in my matrix, I don't know how to assign them randomly to my matrix. And I can't write any line of codes for that to put it here to correct it. Here is an example. Assume that I have numbers 1 and 1.2. I want to generate a 20*10 matrix with its

Converting a dictionary into a square matrix

由 核能气质少年 提交于 2020-01-15 09:01:35
问题 I am wanting to learn how to convert a dictionary into a square matrix. From what I have read, I may need to convert this into a numpy array and then reshape it. I do not want to use reshape as I want to be able to do this based on information a user puts in. In other words, I want a code to give out a square matrix no matter how many owners and breeds are input by the user. Note: The owners and breeds for this dictionary vary upon user input. A user can input 100 names and 50 breeds, or they

Converting a dictionary into a square matrix

由 时光毁灭记忆、已成空白 提交于 2020-01-15 09:01:07
问题 I am wanting to learn how to convert a dictionary into a square matrix. From what I have read, I may need to convert this into a numpy array and then reshape it. I do not want to use reshape as I want to be able to do this based on information a user puts in. In other words, I want a code to give out a square matrix no matter how many owners and breeds are input by the user. Note: The owners and breeds for this dictionary vary upon user input. A user can input 100 names and 50 breeds, or they
订阅 matrix