jsonImportOptions

Create options for importing JSON data.

📝Syntax

opts = jsonImportOptions()
opts = jsonImportOptions('NumVariables', numVars)
opts = jsonImportOptions(..., Name, Value)

📥Input Arguments

Parameter	Description
numVars	number of variables (default: 1).
Name, Value	property names and values of the object, and 'ParsingMode' ('lenient' or 'strict') which sets AllowComments, AllowInfAndNaN and AllowTrailingCommas.

📤Output Arguments

Parameter	Description
opts	nelson.io.json.JSONImportOptions object.

📄Description

jsonImportOptions creates an import options object for JSON files, to use with readtable and readtimetable. detectImportOptions returns the same object, filled from a JSON file.

Properties:

VariableNames: names of the variables (default: Var1, Var2, ...).
VariableNamingRule: 'preserve' (default) or 'modify'.
VariableTypes: types of the variables: 'double', 'single', integer types, 'logical', 'string', 'char', 'categorical', 'datetime', 'duration' or 'cell' (default: 'char').
SelectedVariableNames: subset of the variables to import.
VariableSelectors: RFC 6901 JSON Pointers of the variables, relative to a row object. "Keys" reads the object keys. When empty, all leaf values are read.
RowNamesSelector: JSON Pointer of the row names.
TableSelector: JSON Pointer of the table ("", the default, is the whole file).
VariableDescriptionsSelector, VariableUnitsSelector: JSON Pointers of the variable descriptions and units.
ImportErrorRule, MissingRule: 'fill' (default), 'error', 'omitrow' or 'omitvar'.
RepeatedNodeRule: 'addcol' (default), 'ignore' or 'error'.
AllowComments, AllowInfAndNaN, AllowTrailingCommas: accept comments, Inf and NaN values, trailing commas (default: true).

The object uses the Nelson class nelson.io.json.JSONImportOptions.

💡Examples

Select a nested value of each row:

f = [tempdir, 'students.json']; fid = fopen(f, 'w'); fprintf(fid, '%s', '[{"Name": {"FirstName": "Priya"}}, {"Name": {"FirstName": "Conor"}}]'); fclose(fid); opts = jsonImportOptions('VariableSelectors', "/Name/FirstName", 'TableSelector', "") T = readtable(f, opts)

🕔Version History

Version	Description
2.0.0	initial version

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