enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. pandas (software) - Wikipedia

    en.wikipedia.org/wiki/Pandas_(software)

    However, if data is a DataFrame, then data['a'] returns all values in the column(s) named a. To avoid this ambiguity, Pandas supports the syntax data.loc['a'] as an alternative way to filter using the index. Pandas also supports the syntax data.iloc[n], which always takes an integer n and returns the nth value, counting from 0. This allows a ...

  3. Dataframe - Wikipedia

    en.wikipedia.org/wiki/Dataframe

    Dataframe may refer to: A tabular data structure common to many data processing libraries: pandas (software) § DataFrames; The Dataframe API in Apache Spark;

  4. Retrieval Data Structure - Wikipedia

    en.wikipedia.org/wiki/Retrieval_Data_Structure

    In computer science, a retrieval data structure, also known as static function, is a space-efficient dictionary-like data type composed of a collection of (key, value) pairs that allows the following operations: [1]

  5. Data retrieval - Wikipedia

    en.wikipedia.org/wiki/Data_retrieval

    In order to retrieve the desired data the user presents a set of criteria by a query. Then the database management system selects the demanded data from the database. The retrieved data may be stored in a file, printed, or viewed on the screen. A query language, like for example Structured Query Language (SQL), is used to prepare the queries.

  6. Information retrieval - Wikipedia

    en.wikipedia.org/wiki/Information_retrieval

    Feature-based retrieval models view documents as vectors of values of feature functions (or just features) and seek the best way to combine these features into a single relevance score, typically by learning to rank methods. Feature functions are arbitrary functions of document and query, and as such can easily incorporate almost any other ...

  7. Table (database) - Wikipedia

    en.wikipedia.org/wiki/Table_(database)

    Views also function as relational tables, but their data are calculated at query time. External tables (in Informix [3] or Oracle, [4] [5] for example) can also be thought of as views. In many systems for computational statistics, such as R and Python's pandas, a data frame or data table is a data type supporting the table

  8. Aggregate function - Wikipedia

    en.wikipedia.org/wiki/Aggregate_function

    Common aggregate functions include: Average (i.e., arithmetic mean) Count; Maximum; Median; Minimum; Mode; Range; Sum; Others include: Nanmean (mean ignoring NaN values, also known as "nil" or "null") Stddev; Formally, an aggregate function takes as input a set, a multiset (bag), or a list from some input domain I and outputs an element of an ...

  9. Pointer (computer programming) - Wikipedia

    en.wikipedia.org/wiki/Pointer_(computer_programming)

    No copy of the value pointed to by m is created */ void passByAddress (int * m) {* m = 14;} int main (void) {int x = 3; /* pass a copy of x's value as the argument */ passByValue (x); // the value was changed inside the function, but x is still 3 from here on /* pass x's address as the argument */ passByAddress (& x); // x was actually changed ...