SROTMG/DROTMG |
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| Construct modified Givens rotation | |||||
Usage | VECLIB, VECLIB8: |
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| REAL*4 | d1, d2, x1, y1, param(5) |
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| CALL SROTMG(d1, d2, x1, y1, param) |
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| REAL*8 | d1, d2, x1, y1, param(5) |
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| CALL DROTMG(d1, d2, x1, y1, param) |
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Input | d1 | The scale factor for the “x” row. |
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| d2 | The scale factor for the “y” row. |
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| x1 | The first element of the “x” row. |
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| y1 | The first element of the “y” row. This is the element | |||||||||
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| that is annihilated by the rotation. |
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Output | d1 | The updated scale factor for the “x” row. | |||||||||
| d2 | The updated scale factor for the “y” row. | |||||||||
| x1 | The rotated first element of the “x” row. | |||||||||
| param | Array containing the matrix elements of the modified | |||||||||
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| Givens rotation matrix H and a flag indicating which | |||||||||
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| form the rotation matrix H takes and, therefore, which | |||||||||
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| elements of param are significant. param is usually an | |||||||||
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| argument to the companion subprogram SROTM or | |||||||||
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| DROTM. |
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| param(1) specifies the form of the rotation matrix H, as | |||||||||
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| follows: |
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| param(1) = | H = |
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| 1 |
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| 0 | 1 |
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| param(1) = | H = |
| param(2) | param(4) |
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| param(3) | param(5) |
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| param(4) |
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| param(1) = 0 | H = |
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| param(3) | 1 |
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128HP MLIB User’s Guide