luna

Nonlinear field equation propagator in Julia

installation

First install CoolProp:

using Pkg
Pkg.add(PackageSpec(url="https://github.com/CoolProp/CoolProp.jl", rev="master"))

then install Luna:

Pkg.add(PackageSpec(url="https://github.com/LupoLab/Luna.git", rev="master")

or

] add https://github.com//CoolProp/CoolProp.jl.git
] add https://github.com/LupoLab/Luna.git

running scans

There are several utilities available to easily run arbitrary parameter scans: in Luna.Scans: @scaninit, @scanvar, and @scan; and in Luna.Output: @ScanHDF5Output.

The first step is to write a standard Luna script to run a single simulation in the scan, e.g. for something involving a 30 fs, 1 μJ pulse:

# Lots of setup work...
gausspulse = let τ=30e-15, λ=λ0
    function gausspulse(t)
        It = Maths.gauss(t, fwhm=τ)
        ω0 = 2π*PhysData.c/λ0
        Et = @. sqrt(It)*cos(ω0*t)
    end
end
in1 = (func=gausspulse, energy=1e-6)
inputs = (in1, )
# More setup work...
Luna.run(...) # run the simulation

Then, make the following changes:

1. Put @scaninit [scanname] at the very beginning of the script (after the import statements) e.g.

   @scaninit "energy_duration_scan"
   # Rest of the script
   

2. Create the arrays/ranges to be scanned over in the script itself, and annotate them with @scanvar e.g.

   @scanvar energy = collect(range(1e-6, 10e-6, length=32))
   @scanvar τ = (25:35)*1e-15
   

3. Wrap the main body of the script (excluding the array definitions of step 2.) in a @scan begin...end block. In this block, use the interpolation syntax $ to enter the scan variables wherever they need to be e.g.

   # Copied from step 2.
   @scanvar energy = collect(range(1e-6, 10e-6, length=32))
   @scanvar τ = (25:35)*1e-15
   
   @scan begin
   # Lots of setup work...
   gausspulse = let τ=$τ, λ=λ0
       function gausspulse(t)
           It = Maths.gauss(t, fwhm=τ)
           ω0 = 2π*PhysData.c/λ0
           Et = @. sqrt(It)*cos(ω0*t)
       end
   end
   in1 = (func=gausspulse, energy=$energy)
   inputs = (in1, )
   # More setup work...
   Luna.run(...) # run the simulation
   end
   

   In the @scan begin...end block you also have access to __SCANIDX__ which is a unique identifier for each point in the scan.

To run the scan, you run the script (say it's called energy_duration_scan.jl) from the command line. There are several options:

• julia energy_duration_scan.jl --local simply runs the whole scan locally

• julia energy_duration_scan.jl --range [range] runs the items given by range, which must evaluate to a valid UnitRange. The total number of items is N1 * N2 * N3... where each Ni is the length of one scan array annotated by @scanvar. The first @scanvar statement determines the innermost (fastest varying) loop, the second @scanvar statement the next loop and so forth. In our example above, this means julia energy_duration_scan.jl --range 1:10 would run the first 10 (out of 32) energies for the first pulse duration (25 fs).

• julia energy_duration_scan.jl --batch idx,N (note no spaces between comma and N) runs batch number idx out of a total of N batches. The batches are not sequential, e.g. for N=4, the indices run by the 4 batches are

  idx=1 -> [1, 5, 9, ...]
  idx=2 -> [2, 6, 10, ...]
  idx=3 -> [3, 7, 11, ...]
  idx=4 -> [4, 8, 12, ...]
  

  This mode of running is mostly intended for parallel execution on clusters and workstations

• To run a scan on the workstation (HWLX0003-EPS), use julia energy_duration_scan.jl --condor N. This creates a .sub job script to submit via condor_submit, which will submit N jobs which each run a batch using the --batch option. Note that for this to work, you need to run julia energy_duration_scan.jl --condor N on the workstation rather than your local machine.

• julia energy_duration_scan.jl --cirrus N should only be run on cirrus or another cluster with PBS installed. It makes a jobscript (to be qsubed) which submits N jobs, each of which executes one batch using the --batch option.

output for scans

For HDF5 output with automatic file naming for scans (e.g. energy_duration_scan_00001.h5 etc), use @ScanHDF5Output(...) from Luna.Output. This only works within a @scan begin...end block and will automatically name your files according to the scan name given to @scaninit and the scan index. It will also save the name and current value of any variable scanned over in a group "scanvars" in the group "meta". In our example above, file["meta"]["scanvars"] would contain Dict{String,Any}("τ" => 2.5e-14,"energy" => 1.0e-7).

example script

For a fully worked-out example scan script, see Luna/test/test_scan.jl.