# Initial guess for iterative solver

**URL:** <https://community.freefem.org/t/initial-guess-for-iterative-solver/1641>\
**Category:** General Discussion\
**Created:** [April 2, 2022, 6:57pm UTC](https://community.freefem.org/t/initial-guess-for-iterative-solver/1641 "2022-04-02T18:57:35Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Amin](https://avatars.discourse-cdn.com/v4/letter/a/8e7dd6/32.png) [@Amin](https://community.freefem.org/u/Amin)\
**Post date:** [April 2, 2022, 6:57pm UTC](https://community.freefem.org/t/initial-guess-for-iterative-solver/1641/1 "2022-04-02T18:57:35Z")

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Hello everyone,  
How can I use the initial value for x to solve the system of linear equations Ax = b?

```auto
set(A, solver=GMRES);
x[] = A^-1*b[];

```

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**Author:** ![prj](https://avatars.discourse-cdn.com/v4/letter/p/ecae2f/32.png) [@prj](https://community.freefem.org/u/prj)\
**Post date:** [April 3, 2022, 2:07pm UTC](https://community.freefem.org/t/initial-guess-for-iterative-solver/1641/2 "2022-04-03T14:07:07Z")

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Put your initial guess in `x[]`.

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<div class="post-metadata">

**Author:** ![Amin](https://avatars.discourse-cdn.com/v4/letter/a/8e7dd6/32.png) [@Amin](https://community.freefem.org/u/Amin)\
**Post date:** [April 3, 2022, 4:58pm UTC](https://community.freefem.org/t/initial-guess-for-iterative-solver/1641/3 "2022-04-03T16:58:28Z")

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Thank you very much.