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We use a M/R job to find the pivot p and its index in the matrix(pivot_row, pivot_col). These are all done in PivotMapper and PivotReducer.
1.#2 Compute the rotation parameters.
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The Implementation of M/R job to rotate the matrix is a tricky. We do not rotate the matrix actually in Mapper & Reducer. We do this rotation during we scan over the matrix table. Plz check the code in RotationInputFormat.
1.#4 Rotate the eigenvectors matrix.
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