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Can QR Decomposition Be Actually Faster? Schwarz-Rutishauser Algorithm

by Arthur V. Ratz

Optimizing the performance of the large-sized matrices QR factorization and eigendecomposition, using Schwarz-Rutishauser algorithm

An Optimal Wagner-Fischer Algorithm For Approximate Strings Matching In Python And NumPy

by Arthur V. Ratz

Compute the Levenshtein distance of literal strings effectively by using the Wagner-Fischer (two matrix rows-based) algorithm.

Applying Matrix Transformations in GDI+

by Virendra Kulkarni

Steps to implement the “Fit picture to fill the shape” option in PowerPoint like applications using GDI+

A Simple and Complete Explanation of Neural Networks

by Mahsa Hassankashi

This article also has a practical example for the neural network. You read here what exactly happens in the human brain, while you review the artificial neuron network.

Latest Articles

An Optimal Wagner-Fischer Algorithm For Approximate Strings Matching In Python And NumPy

by Arthur V. Ratz

Compute the Levenshtein distance of literal strings effectively by using the Wagner-Fischer (two matrix rows-based) algorithm.

Can QR Decomposition Be Actually Faster? Schwarz-Rutishauser Algorithm

by Arthur V. Ratz

Optimizing the performance of the large-sized matrices QR factorization and eigendecomposition, using Schwarz-Rutishauser algorithm

A Simple and Complete Explanation of Neural Networks

by Mahsa Hassankashi

This article also has a practical example for the neural network. You read here what exactly happens in the human brain, while you review the artificial neuron network.

The "Camera" and the Projection and View Transforms (Public Domain Geometry Utilities Library)

by Peter Occil

Describes projection and view transforms commonly used in 3D graphics, such as perspective and orthographic transforms

All Articles

Matrix

Fast matrix calculation in VB.NET

3 Oct 2014 by A_Shahn

HI ALL-----I have a fundamental question:What is the best way to perform Matrix-Calculation in VB.NET?!I want to know what is the fastest way to do that?!-----Let me explain it more:I want to do some processing on images,(For example: Apply a gaussian-filter on a...

How to create a histogram with a matrix?

25 Apr 2022 by abc174

So I have a table which holds words and their counts. I want to create a histogram with it but I'm not pretty sure where to start. wordCount() func returns table's row count. What I have tried: public class TestHistogram { public static...

How do I link container to a matrix class

8 Dec 2020 by Afzaal Ahmad Zeeshan

That is why normally it is recommended to not have a long chain of method calls, if any single one of them fails you get a null reference exception. I would suggest rewriting that log line as: var worker = workers.Get(i); if(worker != null) { ...

How to rotate M x N matrix 90° clockwise in C?

19 Nov 2017 by Amar Ćatović

#include int main() { printf("Enter M and N of matrix A: "); int m,n; int p,q; scanf("%i %i",&m,&n); printf("Enter matrix elements: "); int i,j,matA[101][101]; for (i=0; i

Fast matrix calculation in VB.NET

3 Oct 2014 by Andreas Gieriet

Use https://mathnetnumerics.codeplex.com/[^].CheersAndi

How to deal with zeros in gauss jordan matrix inversion

11 Oct 2022 by Animesh jain 2022

I was coding a matrix inversion algorithm It works with almost all of the matrixes except one with zeros in the diagonal entries Like: 8 9 0 0 0 8 0 9 10 and similar if Argument_Matrix[i][i] != 0: Argument_Matrix[i] /=...

How to do matrix multiplication?

12 Sep 2014 by ARMS_DEIR

How to work with matrices and vectors in c++ or c#? How to set matrices of n by m, simply as in matlab that we say A=M*N, what are the needed namespaces or libraries?

Can QR Decomposition Be Actually Faster? Schwarz-Rutishauser Algorithm

3 Jan 2022 by Arthur V. Ratz

Optimizing the performance of the large-sized matrices QR factorization and eigendecomposition, using Schwarz-Rutishauser algorithm

Matlab - add one matrix into the end of another matrix

9 Mar 2022 by Arthur V. Ratz

Here's the solution: And, this is done in MatLab just like in Python and NumPy, such as: For rows: A = ones(1,4); B = zeros(1,4); C = [A B] D = [A;B] For columns: A = ones(2,3) B = zeros(2,2) C = [A B] I basically refer to Creating,...

An Optimal Wagner-Fischer Algorithm For Approximate Strings Matching In Python And NumPy

16 Sep 2022 by Arthur V. Ratz

Compute the Levenshtein distance of literal strings effectively by using the Wagner-Fischer (two matrix rows-based) algorithm.

To detect whether an internal square matrix has its corners are the same characters.

26 Mar 2022 by Atharav Jadhav

I have tried giving input for a 2X2 matrix. 0 1 0 x x 1 y x But the output still is "Matrix not allowed" according to my code, whereas for this input it should just run well. Please let me know where I am going wrong. What I have...

How can I add columns to a Matrix in a BIDS Report project?

21 Jan 2016 by B. Clay Shannon

When I add a Matrix to the Layout page in the BIDS designer, it creates two columns. I need more. I would expect the Matrix control to have a "ColumnCount" property, but it doesn't. My next expectation would be that the Matrix would provide a context-sensitve menu allowing me to insert...

Filling a matrix from user input in text box -- windows forms

15 Apr 2020 by bekim peci

So basically I have to ask the user to input the text in the textBox and then , add that input into the matrix, but the code i have written doesn't give me time to get the user input What I have tried: public void FillMatrix (string...

Calculate eigen value and eigen vector in MPI

18 Apr 2017 by Bhola Ram Sahu

I want to do a small program that calculates eigen value and eigen vector in parallel processors using MPI. I have written a code that works correctly but its for uni processor. Please help me with some code for parallel processor. I want to compare the processing time for different number of...

Faster way to move matrix columns

8 Feb 2021 by Captian Ahab

I just came over from Stack Overflow after getting question banned, so I have no idea how you guys will like me, but here goes. I have a 16x16 matrix, and I'm trying to move the columns to the right. What I have tried: Here's how I have it...

How to do matrix multiplication?

12 Sep 2014 by Christian Amado

Hope these links helps you...Matrix Decomposition[^]C# Matrix Library[^]Matrix multiplication[^]Regards

How do I merge matrix means double dimensional array represented in single array and arrange the matrix in ascending order

7 Jul 2017 by CPallini

The initialization of the matrix is incorrect (not complete). Moreover your sort routine is flawed. Try #include using namespace std; int main() { int a[5][5],i,j,k,t; int * b = reinterpret_cast(a); for(i=0;i>a[i][j]; } ...

Can someone help me to finish this code in C++

10 Jan 2018 by CPallini

Start writing the Matrice and Vector classes (at least their skeletons), then start filling properly the methods. Take advantage, if you can, of the modern features of C++, in order to simplify your task.

How to print all the diagonal elements of a 2d vector in C++

28 Mar 2020 by CPallini

A diagonal starting at (row,0) includes all items (row+k,k) where k=0,1,.., ROWS-row-1. In a similar way, a diagonal starting at (0,col) includes all items (k,col+k) where k=0, 1, .., COLS-col-1. The task is competed if you iterate on rows: row...

I have a problem with my final assignment, can you help me?

14 Jun 2022 by CPallini

You did practically nothing. There are basically three tasks: Matrix computations, that is addition, subtraction, multiplication of two matrices. Matrix input from file and output to file. Interpret the command line and execute it. For...

Take indices of non zero elements of matrix

15 Jun 2022 by CPallini

Try the following code n=3 adjacency_matrix =[ [2, 3, 0] , [0, 0, 1] , [1, 5, 0] ] li_r = [] li_c = [] for i in range(n): for j in range(n): if adjacency_matrix[i][j]!=0: li_r.append(i) li_c.append(j) print(li_r) print(li_c) ...

How to calculate hausdorff distance in pixel between two 3D arrays in Python?

15 Dec 2021 by Enes Şahin 2021

I have two files with nrrd extension. I am reading them by using nrrd module and saving to 3D array. Now I have two 3D arrays and I want to calculate fastly hausdorff distance between them in pixel. And I have to use python. Here is the small...

QR algorithm implementation 3x3 symmetric fixed point

1 Mar 2015 by FranxCDO

I want to find the eigenvalues and eigenvectors of a 3x3 matrix. My numbers are stored in fixed-point format (16.16 to be exact).Note that I don't mind much about the performance, but simply implementing an algorithm that does the job.The code below, when you build it and run it (with...

Multiplication of 32 bits numbers in C

8 Mar 2015 by FranxCDO

I am trying two multiply to matrices in C and I cant understand why I get these results...(I am trying write a program that multiplies two 32 bits numbers to be imported on a system that has only 32 bit registers)B = [ 15643 54056 -33591 24466 26823 54561 58751 ...

Multiplication of 32 bits numbers in C

8 Mar 2015 by FranxCDO

As phil.o and Sergey Alexandrovich Kryukov state above, the problem was with the representation of the numbers. The below code works.#include #include #include #include #define LOW_WORD(x) (((x) > 16) #define HIGH_WORD(x) ((x) >>...

Two dimensional matrix multiplication in mpi

11 Apr 2016 by gd charan

Here is the code for one dimentional matrix multiplication #include #include #include #define SIZE 1024#define FROM MASTER 1 #define FROM WORKER 2#define DEBUG 0 /∗ 1 = debug on, 0 = debug off ∗/MPI Status status;static double...

Convert string into array of matrix

26 Apr 2019 by Gerry Schmitz

How to split a string in C++ - Fluent C++[^]

How to write a program in C to do operations on algebraic expression containing 2 variables?

30 Jul 2017 by Graeme_Grant

Sorry, we do not do your homework for you.

How do I link container to a matrix class

8 Dec 2020 by gsile

I have been trying to link my "person" class values with "workers" class in the "Read" method. When I write Console.WriteLine(person.GetName()); it gives me all the values perfectly, but if I write Console.WriteLine(workers.Get(i).GetName());...

How can I build a matrix in matlab?

5 Nov 2014 by hor_313

HiI want to build a m*n matrix in Matlab but i don't know how? I know I can build a vector with many ways but about matrices I couldn't find any way!For example if I want to build a matrix 100*100 like this:[1 2 3 .......100 1 2 3 .......100 1 2 3 .......100 . . . 1 2 3...

Matlab - add one matrix into the end of another matrix

9 Mar 2022 by JamesDorr

Can you help me with this in Matlab I have this matrix A= 10 20 30 40 60 70 80 90 100 B= 1 1 1 1 1 1 how can i add matrix B into the end of matrix A to look like this C= 10 20 30 40 60 70 80 90 100 1 1 1 What I have...

Create a program displaying number of numbers greater than 0.8 in matrix

4 Nov 2020 by justilian

New programmer here, I got a task to make a program that picks and displays number of numbers greater than 0.8 in a random matrix 5x6 with 2 for loops and would appreciate help if someone knows how to make it. Thanks in advance. this is how...

How to use math formulas with javascript?

6 May 2016 by Karthik_Mahalingam

use Math object refer: JavaScript Math Reference[^]JavaScript Math Functions[^]JavaScript The Math Object[^]Math Object (JavaScript)[^]example:var value = Math.cos(25);alert (value);

computational-geometry

How do I invert an n*n matrix

30 May 2016 by Kenneth Haugland

I have one way of solving the inverse of a matrix, solving it column by column:High precision native Gaussian Elimination[^]I also think you would benefit from reading up on matrixes in general, not just the inverse bit. Matrices are very useful in many areas, but mastering and...

Transpose matrix in matrix multiplication

27 Nov 2017 by Kenneth Haugland

In the header, you ask about matrix multiplication, while in the question you ask about transposing a matrix. Transposing a matrix is just to switch the rows and columns: TransposeA[i][j]=A[j][i] Matrix multiplication is a bit more cumbersome as you need to make sure that the columns in the...

Matrix multiplication in MPI with(C)

30 Nov 2017 by Kenneth Haugland

This seems wrong to me: for(i = 0; i

How to swap matrix quarters clockwise

27 Dec 2014 by Kiber

I want to write a program that:1) Generates quadratic matrix of size (2Nx2N) 2) Prints this matrix3) Swaps the quarters of the matrix clockwise (beginning from top left corner)4) Prints changed matrix.For example, the output of my program should be like this:01 02 03 04 05 06...

C# WPF, how to change RenderTransformOrigin & keep location?

19 Aug 2015 by KingSora

I would like to know how to change RenderTransformOrigin of an element without changing its location? I've noticed that changing the RenderTransformOrigin will affect the element location.How can I calculate the delta X, delta Y between the element location before and after changing the...

CS0246 the type or namespace name 'matrix<float>' could not be found (are you missing a using directive or an assembly reference? )

19 Mar 2016 by KittoKy

In this code I am getting the error : CS0246 The type or namespace name 'Matrix' could not be found (are you missing a using directive or an assembly reference?)#region Generate the training data and classesMatrix trainData = new Matrix(trainSampleCount,...

image-processing

Transpose matrix in matrix multiplication

27 Nov 2017 by Lilyanaa

I find what I need from Stack Overflow and now I have a question,what is the benefit of this function static void transpose_matrix() { int i, j; for(i = 0; i

Matrix multiplication in MPI with(C)

30 Nov 2017 by Lilyanaa

I'm trying to create a simple Matrix Multiplication program with MPI ,the idea of this code is split the first matrix (a) by row and the second matrix(b)by column and send these rows and columns to all processors ,the program must be (first matrix split by rows * second matrix split by columns)...

How do I count the number of "0"s in my matrix of 0s and 1s using R?

13 Mar 2022 by loop063

I have a 15x15 matrix with strings of "0"s and "1"s. I need to find the number of columns that have only one "0". Note that the variables in the matrix are strings, not numerics What I have tried: colSums(m1=="1", na.rm=TRUE)

Finding group of columns with row sum equal one

10 Mar 2022 by Luc Pattyn

Aha, That is a special case of a more general optimisation job I've spent many years on; I ended up with a very nice approach that is the opposite of brute force, and provides all solutions in one go. Applied on your matrix situation, I'd like...

Apply a shear transform to a circle

9 Apr 2014 by lukeer

You can leave the circle (and everything else) unmodified and let the Graphics object deal with shearing via its Transform property. It's of type Matrix, which supports Shaer out of the box.

How can I create a 2D array data, 100*100 with float number between 0 and 10 ?

27 Oct 2021 by M Sanei

I want to create a 2D array data with 100 row and 100 column in which every cell would be a float number between 0 and 10 randomly generated, store row by row. After that implement selection and range queries on it. What I have tried: I have...

How to store multiple function calls in an array

9 Oct 2014 by Maciej Los

Have a look here: Classical Encryption Techniques[^]. There you'll find Hll Cipher algorithm implementation. It might help to solve your issue.MatrixMul function expects result variable as an array of integer. Why don't you use it as an output?private void MatrixMul(string subInput, int[,]...

How to swap matrix quarters clockwise

27 Dec 2014 by Maciej Los

Last few weeks i saw at least few of similar questions[^]. Please, follow them.

Program to find minimum matrix

24 Jun 2019 by Maciej Los

Take a look here: Dijsktra's algorithm[^]

A Simple and Complete Explanation of Neural Networks

3 Apr 2019 by Mahsa Hassankashi

This article also has a practical example for the neural network. You read here what exactly happens in the human brain, while you review the artificial neuron network.

How do I fix "connect 4" stacking and checking the winner

20 Oct 2021 by Matt Weber_1

I'm developing a Connect 4 Python program. When I'm attempting to play the game and trying to "stack" the tokens, instead of doing so they just replace each other after each turn if the other/same user picks the same column. For example, this...

How to swap matrix quarters clockwise

31 Dec 2014 by Member 10641779

Hey, I liked your question so I thought i should work on it. Here m adding the code to change matrix as shown by you in example.Here suppose 'a' is your original matrix of size (2N x 2N) and I have take one `tmp` matrix to store value. it will also be of same sizeinitialize tmp matrix at the...

ms access Matrix / Array database for vb.bet

16 Jun 2014 by Member 10862570

HiI have a problem how to set the data baseI am using Ms access VB.net Strongly typed Data basenow i have 500 products each product got 2 criteria for price W and H so i used to have like a matrix on excel with 500 tables ex first table (Product A)column 100 150 200...

ms access variable query for all the database

16 Jun 2014 by Member 10862570

HII had a problem that coudnt be solved so i ended up having 500 small tables in my access database.exTable A column 100 150 200 300row 50 60 70and the cell intersection is the pricetable bcolumn 135 145 205 310row 54 62 75and the cell intersection is the priceso i...

Matrix Multiplication MPI not working

12 Aug 2014 by Member 11008046

Hello everyone!I am trying to multiply arrays using MPI to speed up the process.My problem is that when i execute the program doesnt work and it freezes.Screenshot:http://s29.postimg.org/ocaxtka2f/image.png[^]Please help me.Thanks in advance.Thats my code:#include...

Matrix element swapping for encryption Java

11 Mar 2015 by Member 11089981

I need to write a program to encrypt and decrypt a given plain text. The input will be a string without spaces. The program should read and store the string as a square matrix, with each element in the matrix being one character. Hence the number of characters in the input string can only be...

I have wrote a code in C to add two matrixes and was unable to print the final output

28 Jun 2022 by Member 12006214

Refer below Code #include int main() { int r, c, i, j, a[100][100], b[100][100], sum[100][100]; printf("Enter the number of rows (between 1 and 100): "); scanf("%d", &r); printf("Enter the number of columns (between 1 and...

Nonogram (Picross) linear solution

30 Nov 2015 by Member 12178113

I need to solve a nonogram problem. My specific problem is to find the maximum number of points that i can put in a nonogram matrix (no need a graphical solution). My input is a sequence of values that represents the maximum number of points for each row and for each coloumn. For example the...

How to use math formulas with javascript?

6 May 2016 by Member 12508138

I created a program located at http://www.ptrone.com/ Where changing the value of z tocos(point)*120+120Creates a circle that is rotating in a circular motion. Can anyone tell the formula to create a triangle that rotates in a circular motion?What I have tried:cos(), sin(), exp()...

computational-geometry

How do I invert an n*n matrix

30 May 2016 by Member 12550760

i want to get the inversion of n*n method so using augmented method so i made the identity matrix then made column reduction then found the inverse for(i=0;i

R - how do I plot a network visualization graph from a x-y coordinate matrix and an adjacency matrix?

10 May 2017 by Member 13191541

In R programming - How do I plot a network visualization graph given a matrix X with a 2 column coordinate system: coordinates

Multiplication error in matrices if I do it in a loop

7 Jun 2017 by Member 13246365

This is my function void clear_up(MatrixXd A, int dim) //to set all initial values of the matrix to 0 { for(int i=0;i

How do I merge matrix means double dimensional array represented in single array and arrange the matrix in ascending order

7 Jul 2017 by Member 13298704

I am not getting correct output What I have tried: void main() { int a[5][5],i,j,k,t; for(i=0;i>a[i][j]; } for(k=0;ka[k+1]) { t=a[k+1]; a[k+1]=a[k]; a[k]=t; } } for(k=0;k

How to write a program in C to do operations on algebraic expression containing 2 variables?

30 Jul 2017 by Member 13336847

How can I add or subtract 2 Algebraic expressions in C which have 2 variables. I realize it could be done using matrix but that would leave many null spaces. Can anyone please write a program dynamically allocating the arrays. How can I do with sparse matrix (array representation) Example...

Can someone help me to finish this code in C++

10 Jan 2018 by Member 13616707

can someone help me to finish this code to work whole in one code. # include ........... ..................... int main() { readMatrice(A,n,m); printMatrice(A,n,m); convertMatriceToVector(A,n,m,V); writeVector(V); sortVector(V); writeVector(V); convertVectorToMatrice(V,n,m,A); ...

Sum of dictionary value

8 Aug 2018 by Member 13770264

Dictionary Matrices = new Dictionary a) { object[] ruleArray = new object[a.Count]; int num = 0; foreach (KeyValuePair

I need help with this function! ! ! !

22 Aug 2018 by Member 13958388

SOMEONE PLEASE HELP ME SOLVE THIS?!?!?!?! SelectKRandomPointsPurposeSelectKRandomPoints generates a list of k randomly selected pixelsfrom an image. Input(s):It takes twoinputs in the following order: 1)A 3D image array from which to select points from 2)The number of points to randomly...

coding-challenge

Can someone help me solve this function please

22 Aug 2018 by Member 13958396

This is my first time doing matlab and I've never coded before. This was a compulsory Uni paper that I have had to take. Prior to this task I've managed to complete various other tasks but this is challenging me beyond what I've learned in the last three weeks. This is what ive got down so far...

image-processing

Pythagorean theorem to check whether a cell is inside the radius

22 May 2019 by Member 14422952

I have the dimensions of a matrix and a given cell with radius. So let's take a look at this example: https://i.imgur.com/51hTJpv.png[Matrix] The matrix has 5 rows and 6 columns. We are given the cell (2, 3) with radius 2. It has an impact, and it destroys all of the items in a certain radius...

Computing Array Determinant for NxN Recursive C#

14 Dec 2019 by Member 14689791

Saruss' Rule can be useful for faster & memory efficient computation of Determinant. because it is non recursive. You can get application on https://github.com/apanasara/Faster_nxn_Determinant

Number of ways to fill a n*m piece matrix with L-shaped three piece tiles

27 Aug 2020 by Member 14924606

I'm looking for an approach to this problem where you have to fill a NxM (N!=M) piece matrix with L-shaped three piece tiles. More accurate to say it s that every element of the matrix is a square and with an L-shaped i cover 3 elements . ...

Finding group of columns with row sum equal one

10 Mar 2022 by Member 15561967

I have a 2D array with ones and zeros, for example: 1 0 0 0 0 1 0 0 1 0 1 0 1 0 0 1 I need to find if there is a group of columns (or a single column) that have a row sum equal 1. For the above array the answer is YES because: 1 + 0 = 1 0 + 1...

How do I print all possible path in matrix except duplicate column # javacode

8 May 2014 by Member 4065983

when I have the Matrix below X1 X2 X3 X4Y1 1.00 0.11 0.07 0.50Y2 0.22 0.07 0.30 0.14Y3 0.00 0.06 0.06 0.08how can I print all following path with java X1Y1-> X2Y2-> X3Y3 -> X4Y3 X3Y2-> X2Y3 -> X4Y3 X4Y2-> X2Y3 ...

How do I print all possible path in matrix except duplicate column

10 May 2014 by Member 4065983

when I have the Matrix below X1 X2 X3 X4Y1 1.00 0.11 0.07 0.50Y2 0.22 0.07 0.30 0.14Y3 0.00 0.06 0.06 0.08how can I print all following path with java X1Y1-> X2Y2-> X3Y3 -> X4Y3 X3Y2-> X2Y3 -> X4Y3 X4Y2-> X2Y3 ...

How do I print all possible path in matrix except duplicate column

18 May 2014 by Member 4065983

Now I implemented a easy source code to find all possible paths in matrix.Then selected the unique row and column.But due to time complexity how can we can get directly unique path.this is my source code. import java.util.*; public class MyAllPath { public static ArrayList...

Simple password generator

15 Feb 2016 by Member 9669321

I saw a great article (I think it was here) about using a matrix to generate strong passwords but easy to remember. It was similar to this one "http://www.labnol.org/software/write-passwords-safely-on-paper/12972/"except that it was a bit simpler. This thing was not a piece of code. It was...

I have a problem with my final assignment, can you help me?

15 Jun 2022 by merano99

Starting here with a user menu does not make much sense. On the contrary, I would leave it out first and the required functions first to read in the matrices and write the functions possible with the matrices. In order to complete the tasks,...

Convert string into array of matrix

26 Apr 2019 by merna adel

It is required to develop a program to do Matrix operations. The program use a defined string format to represent the matrix in the user input and output sections. For the following matrix: examplee : the user input the string representation of the Matrix : ex:[10 2.13 3;-5 0 4;16.5 1 8] In the...

User input matrix print error code

20 Mar 2021 by MMS98

Hi, I have this program which prompts the user for a matrix’ dimensions then for its elements. I have done input validation correctly, but my problems is with asking to input at least the correct number of inputs needed to get the matrix for...

To solve a matrix equation

4 Jun 2017 by Mosi_62

Some ways to solve a matrix equation :-)

Take indices of non zero elements of matrix

15 Jun 2022 by niksirat2030

Hi, I create matrix "adjacency_matrix" with following code: n = int(input()) # Initialize matrix adjacency_matrix = [] # For user input for i in range(n): a =[] for j in range(n): a.append(int(input())) adjacency_matrix.append(a) I...

How to get Matrix of feature vector from quantized spectogram?

21 Apr 2015 by nizam qbixx

Hi..I was doing a research related to speech recognition. So far I already able to convert a sample waveform (.wav format) to a feature vector by using MFCC which generate .mfc file. I also able to read the .mfc file but I dont know how to related it to the spectogram. Actually, I'm not sure...

Program to find minimum matrix

25 Jun 2019 by Noble Badass

Minimum matrix You are given an integer matrix A of size N×M. You start on the left upper corner cell (with coordinates (1,1)). You can walk in four directions. You can not visit the same cell twice. You have to visit every cell of matrix A. When you stand on a cell, your maximum value is...

How do I create a gridlayout of buttons using 2d matrix? (Exended jbutton)

25 Sep 2022 by NoName900

i'm trying to code a Minesweeping game in java and i don't know how to create the board. What I have tried: this is my code: import javax.swing.*; import java.awt.*; public class Board extends JFrame { static final int Col=9; ...

Expression templates and matrix multiplication

15 Nov 2018 by Optimistic76

Hello, I'm trying to understand how mathematical libraries that use Expression Templates techniques ( like Eigen for exmaple ) handle Matrix Multiplication. What I have tried: In many examples I found there is always just the element-wise operation implemented: A = B*C + D is compiled as a...

Expression templates and matrix multiplication

17 Nov 2018 by Optimistic76

I finally found a link i never noticed that answer to my question Eigen: Lazy Evaluation and Aliasing[^]

Multiplication error in matrices if I do it in a loop

7 Jun 2017 by OriginalGriff

Quote: Compiling does not mean your code is right! :laugh: Think of the development process as writing an email: compiling successfully means that you wrote the email in the right language - English, rather than German for example - not that the email contained the message you wanted to send. ...

Setting infinite value (∞) in the input file and reading it in java

26 Aug 2017 by OriginalGriff

There is no such value that you can insert as a number: that is the nature of "infinite values". Instead, I'd write something that wasn't a number at all - a character like 'i' or even '∞' if your file is Unicode and specifically check for that when I read the file back while converting the...

How to rotate M x N matrix 90° clockwise in C?

18 Nov 2017 by OriginalGriff

Compiling does not mean your code is right! :laugh: Think of the development process as writing an email: compiling successfully means that you wrote the email in the right language - English, rather than German for example - not that the email contained the message you wanted to send. So now...

Sum of dictionary value

8 Aug 2018 by OriginalGriff

Quote: 'System.InvalidCastException' Helps a bit, but knowing which line would make our job easier... At a guess, it's this line: m[h,j] =(int)a[i]+(int)a[i+1] ; and it implies that a does not contain integers. So start by looking at what exactly Tab_Mat does return, then use the debugger to...

“Enlarging” a 2D array by factor (m, n)

14 Sep 2018 by OriginalGriff

We do not do your homework: it is set for a reason. It is there so that you think about what you have been told, and try to understand it. It is also there so that your tutor can identify areas where you are weak, and focus more attention on remedial action. Try it yourself, you may find it is...

Pythagorean theorem to check whether a cell is inside the radius

22 May 2019 by OriginalGriff

This is basic maths. targetRow - row is the horizontal distance from the target to the centre of your circle with radius radius, and targetColumn - col is the vertical distance. The radius by definition never shorter than the longest of the absolute values of those two, so it is always the...

Program to find minimum matrix

24 Jun 2019 by OriginalGriff

We are more than willing to help those that are stuck: but that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for us to do it all for you. So we need you to do the...

Write a program using C++ that can read and print matrix

2 Nov 2020 by OriginalGriff

We are more than willing to help those that are stuck: but that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for us...

How do I fix "connect 4" stacking and checking the winner

20 Oct 2021 by OriginalGriff

When you "drop" a token, you need to scan the column and find the first "used slot". The simplest way to do that is to expand the storage area by one in all directions (so that the board matrix for a 3 x 3 board is 5 x 5) and fill the "edges"...

I have a problem with my final assignment, can you help me?

14 Jun 2022 by OriginalGriff

While we are more than willing to help those that are stuck, that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for...

Multiplication error in matrices if I do it in a loop

7 Jun 2017 by Patrice T

Quote: However, when I run it in a loop, some matrices are symmetric whereas some are not. What could be the reason? Serious ? you did not even dared to give an example of the problem. The minimum is an example with calling sequence to reproduce the problem. There is a tool that allow you to...

How do I merge matrix means double dimensional array represented in single array and arrange the matrix in ascending order

7 Jul 2017 by Patrice T

First of all, indent your code properly, it helps reading. void main() { int a[5][5],i,j,k,t; for(i=0;i>a[i][j]; } // this loop is very confusing and lake no sens to me for(k=0;k

How to rotate M x N matrix 90° clockwise in C?

19 Nov 2017 by Patrice T

Quote: It rotates N x N matrix like it should, but there is problem with M x N matrix. You need to take into account that the shape of the matrix changes after transpose. There is a tool that allow you to see what your code is doing, its name is debugger. It is also a great learning tool...

Can someone help me to finish this code in C++

10 Jan 2018 by Patrice T

Quote: can someone help me to finish this code to work whole in one code. Finish what? this code is barely as starting point. All you gave us a couple function names and not explanation. Your teacher is the only one that can help you with no explanation. We do not do your HomeWork. HomeWork is...

I need help with this function! ! ! !

22 Aug 2018 by Patrice T

Quote: SOMEONE PLEASE HELP ME SOLVE THIS?!?!?!?! The help you want is us doing your homeWork. You show no attempt to solve the problem yourself, you have no question, you just want us to do your HomeWork. HomeWork problems are simplified versions of the kind of problems you will have to solve...

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