June 2018
Intermediate to advanced
248 pages
5h 27m
English
Content preview from Mastering Numerical Computing with NumPy
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Indexing, slicing, reshaping, resizing, and broadcasting
When you are working with huge arrays in machine learning projects, you often need to index, slice, reshape, and resize.
Indexing is a fundamental term used in mathematics and computer science. As a general term, indexing helps you to specify how to return desired elements of various data structures. The following example shows indexing for a list and a tuple:
In [74]: x = ["USA","France", "Germany","England"] x[2]Out[74]: 'Germany'In [75]: x = ('USA',3,"France",4) x[2]Out[75]: 'France'
In NumPy, the main usage of indexing is controlling and manipulating the elements of arrays. It's a way of creating generic lookup values. Indexing contains three child operations, which are field access, ...