# AMRClaw for 1d problems¶

**New in Version 5.4.1**

AMRClaw has been extended to support one-dimensional AMR directly.

The setrun.py file has the same form as for 2d AMRClaw, with the obvious changes to eliminate the y-direction. See Sample setrun.py module for AMRClaw.

For some examples, see the 1d examples in $CLAW/amrclaw/examples/ and in gallery_classic_amrclaw.

## Old approach, deprecated:¶

The two-dimensional code can also be used for 1-dimensional problems, by setting num_cells[1] = 1 so there is only one cell in the y direction. Also set refinement_ratios_y = [1,1,1, …] so that refinement is not done in this direction.

In this case the code will automatically do sweeps only in the x-direction and not attempt to solve any Riemann problems in the y-direction, or transverse Riemann problems.

The output in the *fort.q000N* files will be suitable for plotting with the
one-dimensional Python plotting tools, e.g. these files will list the number
of cells in *x* but not in *y*.

**This appears to still have bugs and is being worked on.**