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## CLAWPACK Sample Code

Traffic flow equations with a delta function source term representing an on ramp at x=0. This is implemented using the fractional step approach in src1.f Set D = 0.008 or 0.012 for Figure 17.6 in setprob.data Example [book/chap17/onramp] to accompany the book
[www.clawpack.org/book.html Finite Volume Methods for Hyperbolic Problems] by R. J. LeVeque. Converted to [www.clawpack.org Clawpack 4.6] form in 2011.

#### Plots of results

After running this code and creating plots via "make .plots", you should be able to view the plots in [link: _plots/_PlotIndex.html].

#### Fortran files

[code: Makefile]
Determines which version of fortran files are used when compiling the code with make and specifies where output and plots should be directed. Type "make .help" at the Unix prompt for options.
[code: driver.f]
The driver routine allocates storage and then calls the main Clawpack routine.
[code: setprob.f]
A routine by this name is called by the library routine [clawcode: clawpack/1d/lib/claw1ez.f] and is generally used to set any values needed for the specific problem being solved.
[code: rp1.f]
This is the Riemann solver, which takes the \$q\$ values stored in the arrays ql and qr and returns the waves in the array wave and speeds in the array s that result in solving the Riemann problem at each cell interface, and the fluctuations amdq and apdq. See [claw:doc/rp1.html] for more information about 1d Riemann solvers.
[code: qinit.f]
This subroutine sets the initial data at time \$t=0\$.

#### Python files

[code: setrun.py]
This file contains a function that specifies what run-time parameters will be used. Some parameters that you might want to modify are described in the [www.clawpack.org/doc.html documentation].
[code: setplot.py]
This file contains a function that specifies what plots will be done and sets various plotting parameters.

#### Data files

Warning: These files are generally changed when setting up a run, usually in [code: setrun.py].
[code: claw.data]
This file contains a number of parameter values that are used by CLAWPACK. The values in this file are read by the library routine [clawcode: clawpack/1d/lib/claw1ez.f].
[code: setprob.data]
This file may contain various parameters used in setting the initial conditions or otherwise setting up the problem.

#### Library routines

In addition to the Fortran routines in this library, several library routines from [claw:clawpack/1d/lib] are used. See the [code: Makefile] to determine which ones are used. end_html