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  2. Matrix chain multiplication - Wikipedia

    en.wikipedia.org/wiki/Matrix_chain_multiplication

    The number of possible parenthesizations is given by the (n–1) th Catalan number, which is O(4 n / n 3/2), so checking each possible parenthesization (brute force) would require a run-time that is exponential in the number of matrices, which is very slow and impractical for large n. A quicker solution to this problem can be achieved by ...

  3. Routh–Hurwitz stability criterion - Wikipedia

    en.wikipedia.org/wiki/Routh–Hurwitz_stability...

    In general the Routh stability criterion states a polynomial has all roots in the open left half-plane if and only if all first-column elements of the Routh array have the same sign. All coefficients being positive (or all negative) is necessary for all roots to be located in the open left half-plane.

  4. Anti-diagonal matrix - Wikipedia

    en.wikipedia.org/wiki/Anti-diagonal_matrix

    More precisely, the sign of the elementary product needed to calculate the determinant of an anti-diagonal matrix is related to whether the corresponding triangular number is even or odd. This is because the number of inversions in the permutation for the only nonzero signed elementary product of any n × n anti-diagonal matrix is always equal ...

  5. Heap's algorithm - Wikipedia

    en.wikipedia.org/wiki/Heap's_algorithm

    Claim: If array A has length n, then permutations(n, A) will result in either A being unchanged, if n is odd, or, if n is even, then A is rotated to the right by 1 (last element shifted in front of other elements). Base: If array A has length 1, then permutations(1, A) will output A and stop, so A is unchanged. Since 1 is odd, this is what was ...

  6. Row- and column-major order - Wikipedia

    en.wikipedia.org/wiki/Row-_and_column-major_order

    The programmer must then decide whether or not to rearrange the elements in memory, based on the actual usage (including the number of times that the array is reused in a computation). For example, the Basic Linear Algebra Subprograms functions are passed flags indicating which arrays are transposed. [24]

  7. Sparse matrix - Wikipedia

    en.wikipedia.org/wiki/Sparse_matrix

    In numerical analysis and scientific computing, a sparse matrix or sparse array is a matrix in which most of the elements are zero. [1] There is no strict definition regarding the proportion of zero-value elements for a matrix to qualify as sparse but a common criterion is that the number of non-zero elements is roughly equal to the number of ...

  8. Transition-rate matrix - Wikipedia

    en.wikipedia.org/wiki/Transition-rate_matrix

    In probability theory, a transition-rate matrix (also known as a Q-matrix, [1] intensity matrix, [2] or infinitesimal generator matrix [3]) is an array of numbers describing the instantaneous rate at which a continuous-time Markov chain transitions between states.

  9. Selection algorithm - Wikipedia

    en.wikipedia.org/wiki/Selection_algorithm

    Thus, a problem on elements is reduced to two recursive problems on / elements (to find the pivot) and at most / elements (after the pivot is used). The total size of these two recursive subproblems is at most 9 n / 10 {\displaystyle 9n/10} , allowing the total time to be analyzed as a geometric series adding to O ( n ) {\displaystyle O(n)} .