These methods are explained exhaustively in the "Getting Started" chapters of the documentation. It is strongly recommended to read them completely. The forum is not though to explain the fundamental basics. Thanks.
"These methods are explained exhaustively in the "Getting Started" chapters of the documentation."
Wrong, definetely not exhaustively after comparing Daniel's answer and the documentation. Logical indexing is not even mentioned. The answers to this question is still useful in 2019.
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