flipud

flipud is a function in the MATLAB programming language and its open-source equivalent, Octave. Its primary purpose is to reverse the order of elements in a matrix or array along the first dimension (rows). When applied to a 2D matrix, flipud effectively flips the matrix vertically, swapping the top row with the bottom row, the second row with the second-to-last row, and so on. For a vector, it reverses the order of its elements.

For example, if you have a matrix A, the command flipud(A) will return a new matrix where the rows of A are in reverse order. The columns remain in their original order. This operation is distinct from fliplr, which reverses the order of elements along the second dimension (columns), effectively flipping a matrix horizontally. flipud is a useful tool for data manipulation, particularly in applications involving image processing or signal analysis where reversing the spatial orientation of data is sometimes required. It is a straightforward function that performs a common array transformation.