Tensor[] rhs = new Tensor[params.length]; for (int j = 0; j < params.length; ++j) { Tensor inverted = ApplyIndexMapping.invertIndices(coeffs[j]); for (int i = 0; i < params.length; ++i) { matrix[i][j] = expandAndEliminate(multiplyAndRenameConflictingDummies(coeffs[i], inverted), simplifications);