| #------------------------------------------------------------- |
| # |
| # Licensed to the Apache Software Foundation (ASF) under one |
| # or more contributor license agreements. See the NOTICE file |
| # distributed with this work for additional information |
| # regarding copyright ownership. The ASF licenses this file |
| # to you under the Apache License, Version 2.0 (the |
| # "License"); you may not use this file except in compliance |
| # with the License. You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, |
| # software distributed under the License is distributed on an |
| # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| # KIND, either express or implied. See the License for the |
| # specific language governing permissions and limitations |
| # under the License. |
| # |
| #------------------------------------------------------------- |
| |
| X = read($1); |
| |
| # calculate and same the trans-mult of X |
| Res1 = t(X) %*% X; |
| while(FALSE) {} |
| |
| # find vector V as the last column and matrix X1 as the rest |
| nc = ncol(X); |
| V = X[,nc]; |
| X1 = X[, 1:nc-1]; |
| |
| # use X1 and V to derive trans-mult of X |
| r1 = cbind((t(X1) %*% X1), (t(X1) %*% V)); |
| r2 = cbind((t(V) %*% X1), (t(V) %*% V)); |
| Res2 = rbind(r1, r2); |
| |
| # verify if the sums are same |
| while(FALSE) {} |
| sum1 = sum(Res1); |
| sum2 = sum(Res2); |
| print("original matrix sum = " + sum1); |
| print("rewritten matrix sum = " + sum2); |
| |
| write(Res1, $2, format="text"); |
| write(Res2, $3, format="text"); |