Getting started

Part 1 - Implementing recipes and instructions

The atomic simulation recipes (ASR) is a Python package that assists computational scientists with tools for storing calculation results and related contextual data. To see how this works in practice, we will in the following be implementing functionality for calculating the most stable crystal structure of common metals.

Before we begin we have to initialize a data repository. This is where ASR stores all its data. In practice, it is nothing more than a “.asr” directory, which can be initialized with

$ asr init .
$ ls -a
.
..
.asr

When running, ASR will search for the data repository in the current folder or (stepwise) in any of the parent folders and use the first one found for storage.

Instructions

The most basic element of ASR is an Instruction. Instructions are simply python functions decorated with the asr.instruction() decorator.

To see how this works in practice let’s look at an example:

Listing 1 asr/tutorial.py

@asr.instruction('asr.tutorial')
@asr.argument('crystal_structure', type=str)
@asr.argument('element', type=str)
def energy(element: str, crystal_structure: str) -> float:
    """Calculate the total energy per atom of atomic structure."""
    atoms = bulk(element, crystalstructure=crystal_structure, a=3.6)
    cls = get_calculator_class('emt')
    atoms.calc = cls()
    filt = ExpCellFilter(atoms, mask=[1, 1, 1, 1, 1, 1])
    opt = BFGS(filt, logfile=None)
    opt.run(fmax=0.001)
    energy = atoms.get_potential_energy()
    natoms = len(atoms)
    return round(energy / natoms, 6)

In this example, we have created a file tutorial.py in the asr/ package-folder containing an instruction for calculating the total energy of a bulk metal in a given crystal structure using the effective medium theory (EMT) calculator. The asr.argument() helps ASR to construct a command-line interface to the instruction. Here we have used it to tell ASR that the two arguments of our instruction is to be interpreted as arguments on the command line (asr.option() serves the sames purpose but for command-line options in stead).

The instruction can be run through the asr run command-line interface

$ asr run "asr.tutorial:energy Ag fcc"
In folder: . (1/1)
Running asr.tutorial:energy(element='Ag', crystal_structure='fcc')

As shown in this example, the instruction is assigned a name which is constructed from filename of the containing file, the python package containing that file and the function name, in this case amounting to “asr.tutorial:energy”. The arguments for the instruction is given along with the instruction name enclosed in quotes.

The cache

Whenever an instruction has been run ASR generates an asr.Record containing contextual information about the run, such as the name of the instruction, the parameters and the result. The Record is stored in the “Cache” which is a kind of database for storing calculations. The record can be viewed on the command-line using

$ asr cache ls
               name                       parameters    result
asr.tutorial:energy element=Ag,crystal_structure=fcc -0.000367

The full contents of the record can be shown with

$ asr cache detail name=asr.tutorial:energy
dependencies=None
history=None
metadata=
 created=2021-12-16 21:17:30.774443
 directory=.
 modified=2021-12-16 21:17:30.774443
resources=
 execution_duration=0.5718867778778076
 execution_end=1639685850.774387
 execution_start=1639685850.2025
 ncores=1
result=-0.000367
run_specification=
 codes=
  code=
   git_hash=None
   package=ase
   version=3.23.0b1
  code=
   git_hash=None
   package=asr
   version=0.4.1
 name=asr.tutorial:energy
 parameters=element=Ag,crystal_structure=fcc
 uid=aee3d863d8234913b6f1b4aa53aee324
 version=0
tags=None

As is evident, there is a lot of information stored in a asr.Record, however, right now we want to highlight a couple of these:

• The asr.Record.run_specification.uid property is a random unique identifier given to all records. This can be used to uniquely select records. The Record provides a shortcut to the UID through asr.Record.uid.

• The run_specification.name property stores the name of the instruction. The Record provides a shortcut to the name through Record.name.

• The run_specification.parameters stores the parameters of the given run. The Record object provides a shortcut the parameters through Record.parameters.

• The result property stores the result of the instruction.

An important feature of ASR is that of “caching”. If we run the instruction again with the same input parameters ASR will skip the actual evaluation of the instruction and simply reuse the old result.

$ asr run "asr.tutorial:energy Ag fcc"
In folder: . (1/1)
asr.tutorial:energy: Found cached record.uid=aee3d863d8234913b6f1b4aa53aee324

This is useful in workflows where it is beneficial to not redo expensive calculation steps when it has already been performed once.

Continuing the task of calculating the lowest energy crystal structure we will implement an additional instruction that loops over crystal structures and finds the most stable one

Listing 2 asr/tutorial.py

@asr.instruction('asr.tutorial')
@asr.argument('element', type=str)
def main(element: str) -> str:
    """Calculate lowest energy crystal structure for an element."""
    crystal_structures = [
        'sc', 'fcc', 'bcc', 'diamond',
    ]
    energies = []
    for crystal_structure in crystal_structures:
        en = energy(element, crystal_structure)
        energies.append(en)
    lowest_energy_crystal_structure = min(
        zip(crystal_structures, energies),
        key=lambda item: item[1]
    )[0]

    return lowest_energy_crystal_structure

We say that the python module which contains our two instructions is a “recipe”, ie. a collection of collection of instructions that achieve our goal. The “main”-instruction is the primary user interface to our recipe and as such it is not necessary to state so explicitly when running the main-instruction.

$ asr run "asr.tutorial Ag"
In folder: . (1/1)
Running asr.tutorial:main(element='Ag')
Running asr.tutorial:energy(element='Ag', crystal_structure='sc')
asr.tutorial:energy: Found cached record.uid=aee3d863d8234913b6f1b4aa53aee324
Running asr.tutorial:energy(element='Ag', crystal_structure='bcc')
Running asr.tutorial:energy(element='Ag', crystal_structure='diamond')

We can now check the result using the command-line tool

$ asr cache ls name=asr.tutorial:main
             name parameters result
asr.tutorial:main element=Ag    fcc

Notice here we applied the “name=asr.tutorial:main” selection to select only the record of relevance. As we can see the EMT calculator correctly predicts FCC as the most stable crystal structure for silver.

Let’s also look at the detailed contents of this record

$ asr cache detail name=asr.tutorial:main
dependencies=
 dependency=uid=41d1addb90f64c9980f0d0212003a90a revision=None
 dependency=uid=aee3d863d8234913b6f1b4aa53aee324 revision=None
 dependency=uid=4b9f72b4c5264decaa626bafe7c162a2 revision=None
 dependency=uid=f853317e67694da697fd3d11610f6354 revision=None
history=None
metadata=
 created=2021-12-16 21:17:34.642078
 directory=.
 modified=2021-12-16 21:17:34.642078
resources=
 execution_duration=2.222498893737793
 execution_end=1639685854.642043
 execution_start=1639685852.4195442
 ncores=1
result=fcc
run_specification=
 codes=
  code=
   git_hash=None
   package=ase
   version=3.23.0b1
  code=
   git_hash=None
   package=asr
   version=0.4.1
 name=asr.tutorial:main
 parameters=element=Ag
 uid=870759861aa34db18598db7c6dc7a9e4
 version=0
tags=None

Here we want to highlight asr.Record.dependencies which stores any dependencies of the selected record on any other records, ie., whether data from any other records has been used in the construction of the selected record. A dependency stores the UID and something called the revision (we will get back to this concept later) which can be used to locate the dependencies.

Let’s continue and calculate the most stable crystal structures for various other metals

$ asr run "asr.tutorial Al"
In folder: . (1/1)
Running asr.tutorial:main(element='Al')
Running asr.tutorial:energy(element='Al', crystal_structure='sc')
Running asr.tutorial:energy(element='Al', crystal_structure='fcc')
Running asr.tutorial:energy(element='Al', crystal_structure='bcc')
Running asr.tutorial:energy(element='Al', crystal_structure='diamond')
$ asr run "asr.tutorial Ni"
In folder: . (1/1)
Running asr.tutorial:main(element='Ni')
Running asr.tutorial:energy(element='Ni', crystal_structure='sc')
Running asr.tutorial:energy(element='Ni', crystal_structure='fcc')
Running asr.tutorial:energy(element='Ni', crystal_structure='bcc')
Running asr.tutorial:energy(element='Ni', crystal_structure='diamond')
$ asr run "asr.tutorial Cu"
In folder: . (1/1)
Running asr.tutorial:main(element='Cu')
Running asr.tutorial:energy(element='Cu', crystal_structure='sc')
Running asr.tutorial:energy(element='Cu', crystal_structure='fcc')
Running asr.tutorial:energy(element='Cu', crystal_structure='bcc')
Running asr.tutorial:energy(element='Cu', crystal_structure='diamond')
$ asr run "asr.tutorial Pd"
In folder: . (1/1)
Running asr.tutorial:main(element='Pd')
Running asr.tutorial:energy(element='Pd', crystal_structure='sc')
Running asr.tutorial:energy(element='Pd', crystal_structure='fcc')
Running asr.tutorial:energy(element='Pd', crystal_structure='bcc')
Running asr.tutorial:energy(element='Pd', crystal_structure='diamond')
$ asr run "asr.tutorial Pt"
In folder: . (1/1)
Running asr.tutorial:main(element='Pt')
Running asr.tutorial:energy(element='Pt', crystal_structure='sc')
Running asr.tutorial:energy(element='Pt', crystal_structure='fcc')
Running asr.tutorial:energy(element='Pt', crystal_structure='bcc')
Running asr.tutorial:energy(element='Pt', crystal_structure='diamond')
$ asr run "asr.tutorial Au"
In folder: . (1/1)
Running asr.tutorial:main(element='Au')
Running asr.tutorial:energy(element='Au', crystal_structure='sc')
Running asr.tutorial:energy(element='Au', crystal_structure='fcc')
Running asr.tutorial:energy(element='Au', crystal_structure='bcc')
Running asr.tutorial:energy(element='Au', crystal_structure='diamond')

We can now take a look at the results with

$ asr cache ls name=asr.tutorial:main
             name parameters result
asr.tutorial:main element=Ag    fcc
asr.tutorial:main element=Al    fcc
asr.tutorial:main element=Ni    fcc
asr.tutorial:main element=Cu    fcc
asr.tutorial:main element=Pd    fcc
asr.tutorial:main element=Pt    fcc
asr.tutorial:main element=Au    fcc

From which we can see that the EMT calculator predicts the FCC crystal structure to be the most stable crystal structure for all tested metals which is also true in reality.

Part 2 - Migrations and mutations

It often happens that you want/have to make changes to an existing instruction. For example, you want to add an additional argument, change the return type of the result or change the implementation which requires thinking about what should happen to existing Records in the cache. This is what “migrations” are for.

ASR implements a revisioning system for Records for handling this problem which revolves around defining functions for updating existing records to be compatible with the newest implementation of the instructions.

In the following, we will continue with the example of calculating the most stable crystal structure. It would be interesting to compare some of ASE’s other calculators. However, at the moment, the energy instruction is hardcoded to use the EMT calculator and we will have to update the instruction to supply the calculator as an input argument

Listing 3 asr/tutorial.py

@asr.instruction('asr.tutorial')
@asr.argument('crystal_structure', type=str)
@asr.argument('element', type=str)
@asr.option('--calculator', type=str, default='emt')
def energy(
        element: str,
        crystal_structure: str,
        calculator: str = 'emt',
) -> float:
    """Calculate the total energy per atom of atomic structure."""
    atoms = bulk(element, crystalstructure=crystal_structure, a=3.6)
    cls = get_calculator_class(calculator)
    atoms.calc = cls()
    filt = ExpCellFilter(atoms, mask=[1, 1, 1, 1, 1, 1])
    opt = BFGS(filt, logfile=None)
    opt.run(fmax=0.001)
    energy = atoms.get_potential_energy()
    natoms = len(atoms)
    return round(energy / natoms, 6)

To update the existing records to be consistent with the new implementation we make a mutation that adds the calculator parameter to the existing records and sets it to emt

Listing 4 asr/tutorial.py

@asr.mutation(selector=lambda record: 'calculator' not in record.parameters)
def add_missing_calculator_parameter(record):
    """Fix old records that are missing calculator='emt'."""
    record.parameters.calculator = 'emt'
    return record

As is appararent, a mutation is nothing more than a regular python function decorated with the asr.mutation() decorator. The decorator takes a selector argument which is used to select records to be migrated. The selector will be applied to all existing records and should return a boolean. The function will then be applied for all records that fulfill the selector criterion.

The mutations can be applied through the CLI

$ asr cache migrate
There are 35 unapplied migrations, 0 erroneous migrations and 0 records are up to date.

Run
    $ asr cache migrate --apply
to apply migrations.

To apply the migrations we do

$ asr cache migrate --apply
There are 35 unapplied migrations, 0 erroneous migrations and 0 records are up to date.

record.uid=aee3d863d8234913b6f1b4aa53aee324
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=c3356e5aee5946cab47024a64757969e

record.uid=41d1addb90f64c9980f0d0212003a90a
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=c04ea3c8651247f9ac251122a29a4e70

record.uid=4b9f72b4c5264decaa626bafe7c162a2
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=c3f213d54d9147aab515d279c60a42cc

record.uid=f853317e67694da697fd3d11610f6354
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=0179a0f174ae4a049c948b6fcf9c764e

record.uid=870759861aa34db18598db7c6dc7a9e4
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=8cac007e53df45e09e3e0369e3f481e4

record.uid=bbaba2bd17474a29952986c214e4dbb5
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=6ae7c38213314b5593d8a2d000587a63

record.uid=c04e7cabbc744374bbb7038a6caf5d3e
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=0861bbb600ff48208c6bda998d100d21

record.uid=0c0a237f3e65484fa7fbefa5e23c8ef7
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=31044787a0cf462ab3c0f949aed96e25

record.uid=3d41be859fab4a26857f65a9e96debe0
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=1598240c2fe944dda47a4903fb27392c

record.uid=086563a7a55d49939dab2eb9f78fb887
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=497da4e0ce8f40ec9eaaa343c80d16b8

record.uid=57fe85c80dbd47fa9fe428b1249aaafb
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=60e46cd15e43411bb53b7afbf185ec57

record.uid=01840acf1387412f9be923e6c5c32ded
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=50fff3e3e4a8494086a170c14c6638c7

record.uid=04ec872f905542c583a55fe9f1596b66
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=6d6e4d904ec14928891d459b4b51cbba

record.uid=86a0abab07694ec29aa3105b657d4243
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=993e8bb7c0a44d2bbf51957c174bd578

record.uid=b4e4a5951a984b90aeced1b1ad5525b6
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=b336411b3d34421b87f94ab2682cdb07

record.uid=82d25401af124703b66e818360ba79aa
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=495b5571ea204124a2c0e9bd78f9eb50

record.uid=50fbadc8c6a0416fbaaad79a213d8cc1
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=db795e27fa5b49e1bbf1551a6aa97ac6

record.uid=be782f46b9354562b91683b07a6ea76a
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=b8af4123403d478ea6c35cc57189fdfd

record.uid=0f88976a51e146d0927cbb8d385e774a
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=ce7e3b3e8f2140838453c0d015ecc497

record.uid=67aa9298f0fa4cb28ae59575553ba81f
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=f61ea5b779834bb68c5eedd35dba3d47

record.uid=deb0725d8bb74ebbacad962fa8d7a78c
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=4ced27638b2f455990bbbd86ea1eace3

record.uid=01cdb7dc5ce14c6bb2a12cf4bb3b8dac
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=ab0364f6e9c94da4b303208aaec0c474

record.uid=f573c6905e244bbc9c10c77055aa4268
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=b7b01e2378b6405db9fe56781a1219a6

record.uid=51c37ede9ffb458c82d4cd02bbb7d02f
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=6d650434c7454702b99ab972c97c8f63

record.uid=26d1393694bf407dbc013d1b44bb55f9
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=d7b10b0f53614ac490373fc107b27875

record.uid=d3c30b8ddc894927b248536f4bca0d1d
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=462f89f6d25a48b99e22f87c4f3752f3

record.uid=e3bc52fec04a4b09908cb025b77c1bd9
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=1d569d08793049bd838d70ef1af37092

record.uid=f218f986b5ce4208ad5a5600ae2e49cd
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=af8cfe4c520247e6b7074d8241919123

record.uid=87e653f0a2034ea0a6f7affb0a04781b
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=709b90040a37450cb64ce0d5f30b031c

record.uid=fd52cb80907e4315acfc6ecf6208c43b
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=63066dbcc0b74b9d9cb0d584fe161820

record.uid=175438c794324c70851f5b70b5f3932d
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=daabe888f26c45929515fd2f84c3015e

record.uid=2cd44b66beed4e2e858bc84867f50038
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=b556fbf7697f4157940c9299e8e1e75e

record.uid=f226125b99eb4aeebf1a038bd4b8673b
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=85da87912a3c4518bc674146e514cb2b

record.uid=dbf420f6f1bb4bdeb06d78e1b4771bcc
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=47da0cd3986643ef98554168d59f09a2

record.uid=12138065a3fd48ea9a5e68088145d11c
Revision #0 changes=New attribute=.run_specification.parameters.calculator value=emt
description=Fix old records that are missing calculator='emt'.
mutation_uid=None
uid=77c6d8b392c7417699ecbd09bcbcab2a

The output informs us of the changes made to the existing records, in particular that the parameters have been updated with a new calculator attribute named EMT. ASR figures this out by comparing the input and output record of the migration and translates this into to a list of actual changes. This makes it possible to revert these changes in case of errors. Let’s look at the details of one of the updated records

$ asr cache detail name=asr.tutorial:energy parameters.element=Ag parameters.crystal_structure=fcc
dependencies=None
history=
 latest_revision=c3356e5aee5946cab47024a64757969e
 revision=
  changes=New attribute=.run_specification.parameters.calculator value=emt
  description=Fix old records that are missing calculator='emt'.
  mutation_uid=None
  uid=c3356e5aee5946cab47024a64757969e
metadata=
 created=2021-12-16 21:17:30.774443
 directory=.
 modified=2021-12-16 21:17:30.774443
resources=
 execution_duration=0.5718867778778076
 execution_end=1639685850.774387
 execution_start=1639685850.2025
 ncores=1
result=-0.000367
run_specification=
 codes=
  code=
   git_hash=None
   package=ase
   version=3.23.0b1
  code=
   git_hash=None
   package=asr
   version=0.4.1
 name=asr.tutorial:energy
 parameters=element=Ag,crystal_structure=fcc,calculator=emt
 uid=aee3d863d8234913b6f1b4aa53aee324
 version=0
tags=None

The changes to the record has been stored in the asr.record.history attribute as a series of revisions (in this case we only have one revision). Each revision is assigned a random UID which can be used to identify the record revision. It is the latest revision ID that is used when identifying dependencies.

We can now run our updated instructions employing other calculators. Here we will investigate the results when using the Lennard-Jones calculator identified as “lj” according to ASE.

$ asr run "asr.tutorial Ag --calculator lj"
In folder: . (1/1)
Running asr.tutorial:main(element='Ag', calculator='lj')
Running asr.tutorial:energy(element='Ag', crystal_structure='sc', calculator='lj')
Running asr.tutorial:energy(element='Ag', crystal_structure='fcc', calculator='lj')
Running asr.tutorial:energy(element='Ag', crystal_structure='bcc', calculator='lj')
Running asr.tutorial:energy(element='Ag', crystal_structure='diamond', calculator='lj')
$ asr run "asr.tutorial Al --calculator lj"
In folder: . (1/1)
Running asr.tutorial:main(element='Al', calculator='lj')
Running asr.tutorial:energy(element='Al', crystal_structure='sc', calculator='lj')
Running asr.tutorial:energy(element='Al', crystal_structure='fcc', calculator='lj')
Running asr.tutorial:energy(element='Al', crystal_structure='bcc', calculator='lj')
Running asr.tutorial:energy(element='Al', crystal_structure='diamond', calculator='lj')
$ asr run "asr.tutorial Ni --calculator lj"
In folder: . (1/1)
Running asr.tutorial:main(element='Ni', calculator='lj')
Running asr.tutorial:energy(element='Ni', crystal_structure='sc', calculator='lj')
Running asr.tutorial:energy(element='Ni', crystal_structure='fcc', calculator='lj')
Running asr.tutorial:energy(element='Ni', crystal_structure='bcc', calculator='lj')
Running asr.tutorial:energy(element='Ni', crystal_structure='diamond', calculator='lj')
$ asr run "asr.tutorial Cu --calculator lj"
In folder: . (1/1)
Running asr.tutorial:main(element='Cu', calculator='lj')
Running asr.tutorial:energy(element='Cu', crystal_structure='sc', calculator='lj')
Running asr.tutorial:energy(element='Cu', crystal_structure='fcc', calculator='lj')
Running asr.tutorial:energy(element='Cu', crystal_structure='bcc', calculator='lj')
Running asr.tutorial:energy(element='Cu', crystal_structure='diamond', calculator='lj')
$ asr run "asr.tutorial Pd --calculator lj"
In folder: . (1/1)
Running asr.tutorial:main(element='Pd', calculator='lj')
Running asr.tutorial:energy(element='Pd', crystal_structure='sc', calculator='lj')
Running asr.tutorial:energy(element='Pd', crystal_structure='fcc', calculator='lj')
Running asr.tutorial:energy(element='Pd', crystal_structure='bcc', calculator='lj')
Running asr.tutorial:energy(element='Pd', crystal_structure='diamond', calculator='lj')
$ asr run "asr.tutorial Pt --calculator lj"
In folder: . (1/1)
Running asr.tutorial:main(element='Pt', calculator='lj')
Running asr.tutorial:energy(element='Pt', crystal_structure='sc', calculator='lj')
Running asr.tutorial:energy(element='Pt', crystal_structure='fcc', calculator='lj')
Running asr.tutorial:energy(element='Pt', crystal_structure='bcc', calculator='lj')
Running asr.tutorial:energy(element='Pt', crystal_structure='diamond', calculator='lj')
$ asr run "asr.tutorial Au --calculator lj"
In folder: . (1/1)
Running asr.tutorial:main(element='Au', calculator='lj')
Running asr.tutorial:energy(element='Au', crystal_structure='sc', calculator='lj')
Running asr.tutorial:energy(element='Au', crystal_structure='fcc', calculator='lj')
Running asr.tutorial:energy(element='Au', crystal_structure='bcc', calculator='lj')
Running asr.tutorial:energy(element='Au', crystal_structure='diamond', calculator='lj')

Let’s check the results

$ asr cache ls name=asr.tutorial:main
             name                parameters result
asr.tutorial:main element=Ag,calculator=emt    fcc
asr.tutorial:main element=Al,calculator=emt    fcc
asr.tutorial:main element=Ni,calculator=emt    fcc
asr.tutorial:main element=Cu,calculator=emt    fcc
asr.tutorial:main element=Pd,calculator=emt    fcc
asr.tutorial:main element=Pt,calculator=emt    fcc
asr.tutorial:main element=Au,calculator=emt    fcc
asr.tutorial:main  element=Ag,calculator=lj    fcc
asr.tutorial:main  element=Al,calculator=lj    fcc
asr.tutorial:main  element=Ni,calculator=lj    fcc
asr.tutorial:main  element=Cu,calculator=lj    fcc
asr.tutorial:main  element=Pd,calculator=lj    fcc
asr.tutorial:main  element=Pt,calculator=lj    fcc
asr.tutorial:main  element=Au,calculator=lj    fcc

In conclusion, the Lennard-Jones calculator also predict fcc as the most stable crystal structure.