Next: Orthogonality of the gradients
Up: Fomel: Conjugate directions
Previous: ALGORITHM
The adjoint operator projects the data space back to the
model space and is defined by the dot product test
| |
(27) |
for any and . The method of conjugate gradients is
a particular case of the method of conjugate directions, where the
initial search direction is
| |
(28) |
This direction is often called the gradient, because it
corresponds to the local gradient of the squared residual norm with
respect to the current model . Aligning the initial
search direction along the gradient leads to the following remarkable
simplifications in the method of conjugate directions.
Next: Orthogonality of the gradients
Up: Fomel: Conjugate directions
Previous: ALGORITHM
Stanford Exploration Project
11/12/1997