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rename(), which enables a user to alter the column names for variables, often to improve ease of use and intuitive understanding of a dataset; slice_max() , which returns a data subset that contains the rows with the highest number of values for some particular variable;
In relational algebra, a rename is a unary operation written as / where: . R is a relation; a and b are attribute names; b is an attribute of R; The result is identical to R except that the b attribute in all tuples is renamed to a. [1]
A column may contain text values, numbers, or even pointers to files in the operating system. [2] Columns typically contain simple types, though some relational database systems allow columns to contain more complex data types, such as whole documents, images, or even video clips. [3] [better source needed] A column can also be called an attribute.
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The C standard library provides a function called rename which does this action. [1] In POSIX, which is extended from the C standard, the rename function will fail if the old and new names are on different mounted file systems. [2] In SQL, renames are performed by using the CHANGE specification in ALTER TABLE statements.
Abstract index notation (also referred to as slot-naming index notation) [1] is a mathematical notation for tensors and spinors that uses indices to indicate their types, rather than their components in a particular basis. [2] The indices are mere placeholders, not related to any basis and, in particular, are non-numerical.
The index terms were mostly assigned by experts but author keywords are also common. The process of indexing begins with any analysis of the subject of the document. The indexer must then identify terms which appropriately identify the subject either by extracting words directly from the document or assigning words from a controlled vocabulary ...
IPNI is the product of a collaboration between The Royal Botanic Gardens, Kew (Index Kewensis), The Harvard University Herbaria (Gray Herbarium Index), and the Australian National Herbarium . The IPNI database is a collection of the names registered by the three cooperating institutions and they work towards standardizing the information.