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Tag: matrix

Java – generate and rotate matrix

recently I’m trying to learn Java a bit and currently, I’m working on a simple program that should generate a matrix and then rotate it. I’m stuck at the first part. What exactly is the problem? The logic of my code seems to be fine, but anyway program is returning not what I would expect. The code: Output: Please, enter

How to check if contours are the same?

I’ve got two images, the second one is the first one after modification. I find contours of two images and then check if there any same contours. The problem is, that despite contours being the same (drawing contours of one image and another one gives totally same results) after checking that it never becomes true that one contour is equal

Java: Inverse of a matrix using EJML not working as expected

Within a java project I’ve developed I need to calculate the inverse of a matrix. In order to align with other projects and other developers I’m using the Efficient Java Matrix Library (orj.ejml). For inverting the Matrix I’m using invert from org.ejml.ops.CommonOps, and I has worked fine until now that I’m getting a unexpected result I’ve isolated the case that

How to get Cartesian product from multiple lists?

Say I have several List<T>s, I will put them into another list or other collections, so I don’t know how many list<T> I have until I call List<List<T>>.size() Take below List<Integer> as an example: How can I get the result of list1*list2*list3*…listn as a Cartesian product? For example: should be: Answer You can use recursion to achieve it, your base

Transposing a matrix from a 2D array

I’m self teaching myself some java and I’m stuck on creating a 2D array that initializes it with random values and then creates the transpose of the array. An example output is: Original matrix Transposed matrix ^ Should be the final output. Some help with the code would appreciated! I would like to code to generate error messages if the