# CG

Provides parameters to tune the conjugate gradient optimization [Edit on GitHub]

Subsections

- LINE_SEARCH

## Keywords

- FLETCHER_REEVES

- MAX_STEEP_STEPS

- RESTART_LIMIT

## Keyword descriptions

FLETCHER_REEVES: logical = F

  Lone keyword: `T`

  Usage: FLETCHER_REEVES

  Uses FLETCHER-REEVES instead of POLAK-RIBIERE when using Conjugate Gradients [Edit on GitHub]

MAX_STEEP_STEPS: integer = 0

  Usage: MAX_STEEP_STEPS {integer}

  Maximum number of steepest descent steps before starting the conjugate gradients optimization. [Edit on GitHub]

RESTART_LIMIT: real = 9.00000000E-001

  Usage: RESTART_LIMIT {real}

  Cosine of the angle between two consecutive searching directions. If the angle during a CG optimization is less than the one corresponding to to the RESTART_LIMIT the CG is reset and one step of steepest descent is performed. [Edit on GitHub]