TabularStructure

TabularStructure[tab]

gives structural information about the Tabular tab for each column.

TabularStructure[tab,cols]

gives structural information for the columns cols.

TabularStructure[tab,cols,props]

selects the properties props to report.

更多信息

  • TabularStructure is typically used to get structural information for each column.
  • TabularStructure[tab,cols,props] returns another Tabular object in which the properties props are column keys and the columns cols are entries in a key column called "ColumnKey". Each row contains information for one of the original columns.
  • Possible forms cols of column specification include:
  • Allall columns of the input Tabular data
    {col1,col2,…}list of columns of the input data
    spattstring pattern for the column keys of the data
    critcriterion function to select columns keys
  • Possible string patterns spatt include strings with wild characters, such as "col*" and StringExpression objects such as "col"~~__.
  • The criterion function crit takes named variables #ColumnKey, providing the column key, and #ElementType, providing the type of the elements of the column.
  • Possible properties props include:
  • "ColumnType"type of the column
    "MissingCount"number of missing elements in the column
    "NonMissingCount"number of non-missing elements in the column
    "ByteCount"byte count of the column
    "DuplicateFreeQ"whether the column has unique entries
    "CountDistinct"number of unique entries
    {prop1,prop2,…}list of properties propi above
    Alllist of all the properties above
    Automaticautomatic choice of some of the properties above

范例

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基本范例  (1)

Build a tabular report about the columns of a Tabular object:

Include only some columns and report only about some properties:

Scope  (3)

Take tabular data about the Titanic passengers:

Compute a structural summary of the data:

Add more properties, including information about possible duplication of entries in each column:

Take tabular data about the elements:

Find a structural summary for some of the columns:

Restrict to only one column:

Report only about the original columns that contain "u" in their name:

Restrict to the columns of "Integer64" type:

Take tabular data about the Titanic passengers:

Find a structural report with the default properties:

Include all available properties, including some reporting about the possible presence of duplicate entries:

Select only one property:

Select several properties:

Applications  (1)

Find out which columns of a Tabular object could be used as key columns for indexing it:

Only duplicate-free columns can be key columns, so that rows are uniquely identified by their values:

Use for example the "state" column, after extracting a subset of the columns:

Properties & Relations  (3)

TabularStructure[tab] returns a Tabular object whose key column contains the column keys of tab:

TabularStructure of an anonymous Tabular object does not have the key column:

Take a Tabular object:

A structural summary about zero columns will contain no rows:

A structural summary with zero properties will contain no columns other than the key column:

Wolfram Research (2025)，TabularStructure，Wolfram 语言函数，https://reference.wolfram.com/language/ref/TabularStructure.html.

文本

Wolfram Research (2025)，TabularStructure，Wolfram 语言函数，https://reference.wolfram.com/language/ref/TabularStructure.html.

CMS

Wolfram 语言. 2025. "TabularStructure." Wolfram 语言与系统参考资料中心. Wolfram Research. https://reference.wolfram.com/language/ref/TabularStructure.html.

APA

Wolfram 语言. (2025). TabularStructure. Wolfram 语言与系统参考资料中心. 追溯自 https://reference.wolfram.com/language/ref/TabularStructure.html 年

BibTeX

@misc{reference.wolfram_2025_tabularstructure, author="Wolfram Research", title="{TabularStructure}", year="2025", howpublished="\url{https://reference.wolfram.com/language/ref/TabularStructure.html}", note=[Accessed: 15-January-2025 ]}

BibLaTeX

@online{reference.wolfram_2025_tabularstructure, organization={Wolfram Research}, title={TabularStructure}, year={2025}, url={https://reference.wolfram.com/language/ref/TabularStructure.html}, note=[Accessed: 15-January-2025 ]}