Project Settings

Description

Holds CASM project settings.

It is recommended to modify settings using the casm settings command.

Project files

This format is used for the project_settings.json file, which is generated when a project is initialized with casm init.

JSON Attributes List

Project Settings attributes:

Name	Description	Format
`cluster_expansions`	Named cluster expansions	dict
`crystallography_tol`	Tolerance used for crystallographic comparisons	number
`default_clex`	Name of the default cluster expansion	string
`lin_alg_tol`	Tolerance used for linear algebra	number
`name`	Project name / title	string
`nlist_sublat_indices`	Indices of sublattices included in the neighbor list	array of int
`nlist_weight_matrix`	Matrix used to determine the order of unit cells in the neighbor list	2d array of int
`query_alias`	Stores `casm query` aliases	dict
`required_properties`	List of properties required for a particular `<calctype>` calculation to be complete	dict
`view_command`	Command to support viewing POSCAR representations of configurations	string

JSON Attributes Description

Project Settings JSON Object

cluster_expansions: dict

Named cluster expansions. The named cluster expansions make it easier to select the choice of basis set, calculation settings, reference, and ECI fit used to predict a particular property, and to switch and compare among multiple possible choices stored in a single CASM project.

A single cluster expansion includes the choice of values for <property>, <calctyp>, <ref>, <bset>, and <eci> used to read data from project directories.
Example:
```
"cluster_expansions" : {
  "formation_energy" : {
    "bset" : "default",
    "calctype" : "default",
    "eci" : "default",
    "name" : "formation_energy",
    "property" : "formation_energy",
    "ref" : "default"
  },
  "formation_energy_lda" : {
    "bset" : "default",
    "calctype" : "lda",
    "eci" : "default",
    "name" : "formation_energy",
    "property" : "formation_energy",
    "ref" : "default"
  }
}
```
crystallography_tol: number (optional, default=1e-5)

Tolerance used for crystallographic comparisons.
default_clex: string (optional)

Name of the default cluster expansion to use when not otherwise specified. A key in cluster_expansions. If not present, "formation_energy" is used. If that is also not present, then the first found is used.
lin_alg_tol: number (optional, default=1e-10)

Tolerance used by some methods when a stricter tolerance is needed for linear algebra, such as identifying the rank of a space.
name: string

Project name. Typically read from “title” in [prim.json] when a project is initialized.
nlist_sublat_indices: array of int

Indices of sublattices included in the neighbor list. Typically determined from the prim and does not need to be modified. If for some reason it is modified, all basis set source code must be re-generated using casm bset -uf.
nlist_weight_matrix: 2d array of int

Used in determining the order of unit cels in the neighbor list. The default value is determined from the prim lattice vectors. Typically does not need to be modified. If for some reason it is modified, all basis set source code must be re-generated using casm bset -uf.

query_alias: dict

Stores casm query aliases.

Example:

"query_alias" : {
  "Configuration" : {
    "is_dilute_O" : "and(lt(comp_n(O),0.01001),gt(comp_n(O),0.00001))",
  },
  "Supercell" : {
    "is_vol_4" : "eq(scel_size,4)"
  }
}

required_properties: dict

List of properties required for a particular <calctype> calculation to be complete.
Example:
```
"required_properties" : {
  "Configuration" : {
    "default" : [ "energy" ],
    "lda": [ "energy" ]
  }
}
```
view_command: string

Command to support viewing POSCAR representations of configurations directly from the casm view command.
Example: On Mac OSX, the following command uses the casm.view script installed by casm-python to view POSCAR representations of configurations in VESTA.
```
"view_command" : "casm.view \"open -a /Applications/VESTA/VESTA.app\""
```