Basilisk source code (

root / src / test

# Test cases

The following test cases are run automatically whenever the code

Note that only the documented test cases appear in the list below
(follow the [All tests](/src/test/) link for a complete list).

## Systems of conservation laws

* [Bouncing Saint-Venant bump](bump2D1.c)
* [1D arterial flow](artery1D.c)
* [Two- and three-dimensional explosions](explosion.c)

## Incompressible Euler/Navier--Stokes

* [Lid-driven cavity at Re=1000](lid.c)
* [Merging of two vertices](stream.c)
* [Merging of two vortices (centered Euler solver)](vortex.c)
* [Taylor--Green vortices](taylor-green.c)

## Shallow-water flows

* [Drying of a lake](dry.c)
* [Simple Saint-Venant Riemann problem](bore1.c)
* [Oscillations in a parabolic container](parabola.c)
* [Undular bores for the Green-Naghdi equations](bore.c)
* [Green-Naghdi soliton](soliton.c)
* [Solitary wave run-up on a plane beach](beach.c)
* [Solitary wave overtopping a seawall](seawall.c)
* [Sinusoidal wave propagation over a bar](bar.c)
* [Runup of a solitary wave on a conical island](conical.c)
* [Shock reflection by a circular cylinder](shock.c)
* [Flow rates for multiple rivers](multiriverinflow.c)
* [Source of a river](source.c)
* [Implicit Saint-Venant solutions for waves](implicit.c)
* [Viscous hydraulic jump](higuera.c)
* [Transcritical flow over a bump with multiple layers](layered.c)
* [Wind-driven lake](wind-driven.c)
* [Lake flowing into itself](lake-tr.c)

## Volume-Of-Fluid

* [Computation of volume fractions from a levelset function](fractions.c)
* [Computation of volume fractions on a variable-resolution grid](fractions1.c)
* [Fractions in marginal cases](fractions2.c)
* [Computation of a levelset field from a contour](basilisk.c)
* [Time-reversed VOF advection in a vortex](reversed.c)

## Surface tension

* [Curvature of a circular/spherical interface](curvature.c)
* [Circular droplet in equilibrium](spurious.c)
* [Capillary wave](capwave.c)
* [Gravity wave](gravity.c)
* [Shape oscillation of an inviscid droplet](oscillation.c)
* [Rising bubble](rising.c)

## General orthogonal coordinates

* [Circular dam break on a sphere](lonlat.c)
* [Axisymmetric mass conservation](axiadvection.c)
* [Axisymmetric Poiseuille flow](poiseuille-axi.c)
* [Convergence of axisymmetric viscous terms](axi.c)
* [Refinement of axisymmetric metric](refine-axi.c)

## Electrohydrodynamics

* [Gouy-Chapman Debye layer](debye.c)
* [Electrostatic in planar layers](planar.c)
* [Convergence of axisymmetric EHD stresses](ehd_axi_stress.c)
* [Charge relaxation in an axisymmetric insulated conducting column](cyl_axi.c)
* [Charge relaxation in a planar cross-section](cyl_planar.c)
* [Equilibrium of a droplet suspended in an electric field](taylor.c)

## Viscoelasticity

* [Transient planar Poiseuille flow for 
   an Oldroyd-B or FENE-P fluid](poiseuille-oldroydb.c)
* [Oldroyd-B lid-driven cavity](lid-oldroydb.c)
* [Viscoelastic 2D drop in a Couette Newtonian shear flow](viscodrop.c)
* [Impact of a viscoelastic drop on a solid](fall.c)

## Reaction--Diffusion

* [The SAG equation](sag.c)

## MPI

* [Reduction operations](mpi-reduce.c)
* [Boundary conditions and restriction](mpi-restriction.c)
* [Z-order indexing](indexing.c)
* [Parallel scalability](mpi-laplacian.c)
* [Parallel refinement](mpi-refine.c)
* [Poisson solver on non-uniform mesh](mpi-circle.c)
* [Boundary conditions for face fluxes](mpi-flux.c)
* [Boundary conditions for face vector fields](mpi-interpu.c)
* [Simple test of Basilisk View](view.c)

## Speed benchmarks

* [Speed of elementary operations on different grids](laplacian.c)

## Other

* [Kuramoto--Sivashinsky equation](kuramoto.c)
* [Convergence of the Runge--Kutta solvers](runge-kutta.c)

## [All tests](/src/test/)

# Running and creating test cases (and examples)

First make sure to read the [section on
Makefiles](/Tutorial#using-makefiles) in the [tutorial](/Tutorial).

To run a particular test case yourself, you can then just do

cd src/test
make bump2D1.tst

which should give something like

    qcc -g -O2 -Wall -o bump2D1/bump2D1 bump2D1.c -lm

This indicates that the test compiled and ran successfully. 

## Error checking

If the test fails, you will get something like

    > 2.5 434 0.0678117 0.164104 0.11299303
    > # refined 80 cells, coarsened 108 cells
    make: *** [bump2D1.tst] Error 1

The last line indicates that make failed. The lines before this are
the output of

diff bump2D1/log bump2D1.ref

That is, to check whether the test case succeeded or not, the default
Makefile of Basilisk just compares (using
[*diff*]( the *log*
file created by the program to the matching reference log file (with
the *.ref* extension).

To create your own test case (let's call it *mytest*), you only need
to create the source code (i.e. *mytest.c*), run it to create the
*mytest/log* file, check that you are happy with the results and copy
*mytest/log* into *mytest.ref*.

## Graphics

Most tests (but not all) also produce some kind of graph summarising
the results (which allows for example to understand more easily
how/why a particular test failed). Some tests produce these graphs
directly when they run, but most rely on *gnuplot* to generate the
graphs in a post-processing step.

This step is not automatically executed when doing *make
test.tst*. This allows for example to run the test suite on *bare
bones* systems which do not have gnuplot installed.

The makefile system knows about two kinds of graphics: *"inline" plots*
and *"offline" plots*.

### Inline plots

These are generated using gnuplot or python commands embedded directly
in the documentation comments of the source code (*mytest.c*). Using
the standard wiki syntax for scripts these commands appear as

    ~~~gnuplot Caption
    set output 'plotname.png'

    ~~~pythonplot Caption
    import matplotlib.pyplot as plt

and are replaced by the corresponding figure when the page is displayed
in the wiki. Note that for gnuplot the *set output* command is optional. If you 
don't supply a file name, a unique name looking like *_plot1.png* will be
generated automatically. For python the *savefig* command is mandatory.

To generate the figures from the command line, just do

make mytest/plots

### Offline plots

Alternatively, one can put the gnuplot commands in a separate 
*mytest.plot* file. Note that this method offers few advantages
compared to "inline plots" (the prefered option).

To generate the corresponding plots, one can then do

make bump2D1/plot.png

which should give something like

    cd bump2D1 && gnuplot -e "batch=1; PNG=\"pngcairo\" ... ../bump2D1.plot ...

Note that, while *plot.png* is the default name for the generated
graph, the gnuplot script can also generate other graphs. Doing

ls bump2D1/*.png

(or *`eog bump2D1/*.png`*) reveal them all.

Note that if you try to generate plots for a test case which does not
have a corresponding *.plot* gnuplot script, you will get something

make events/plot.png
make: *** No rule to make target `events/plot.png'.  Stop.

## Running the entire test suite

Use something like

cd src/test/
make -k -j8

where *-k* tells *make* not to stop at the first error and *-j8* uses
parallel processing (assuming you have at least 8 cores on your

If you want to generate all the graphs at once, do

make plots