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MissingDataRules

MissingDataRules

MissingDataRules

is an option for SemanticImport and related functions that specifies what should be considered "missing" and what to replace it with.

Details

MissingDataRules->{s₁->val₁,s₂->val₂,…} specifies that whenever an element has the form of a string or string pattern s_i, it should be replaced in the output by a Missing incorporating val_i.
MissingDataRules-><|name₁->{s₁->val₁,…},name₂->…,…|> specifies replacements to use in columns with names name_i.
MissingDataRules->{{s₁->val₁,…},…} specifies replacements to use in successive columns.
If val_i is of the form Missing[…], it is used directly.
MissingDataRules->Automatic uses heuristics to determine which elements should be considered missing.

Examples

Basic Examples (5)

Specify how to handle missing data:

Match missing data by pattern:

Handle missing data differently in each column:

Handle missing data in the second column only:

Specify how to handle missing data by column name:

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