# A tutorial on the conjugate gradient method, a method to solve large linear problems

### What is it about?

The conjugate gradient method can be used to solve many large linear geophysical problems like least squares migration and full waveform inversion. This tutorial provides simple code to solve an easily to understood problem to demonstrate the method. The code can easily be adapted to solve a large linear inversion problem.

### Why is it important?

The conjugate gradient method is often used to solve large problems because the more familiar linear algebra method like gaussian elimination are much more expensive — that is, even a large computer may not be able to find a useful solution in a reasonable amount of time.

### Perspectives

The following have contributed to this page: Karl Schleicher

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