Comprehensive Guide to Numpy Arrays: shape, Indexing, and Slicing
NumPy arrays are the foundation of Python data analysis, providing efficient multi-dimensional array objects with core operations including array creation, shape manipulation, indexing, and slicing. Creation methods: np.array() is commonly used to generate arrays from lists; zeros/ones create arrays filled with 0s/1s; arange generates sequences similar to Python's range. Shape is the dimension identifier of an array, viewed via .shape. The reshape() method adjusts dimensions (total elements must remain unchanged), with -1 indicating automatic dimension calculation. Indexing: 1D arrays behave like lists (0-based indexing with support for negative indices); 2D arrays use double indexing [i, j]. Slicing: Follows the syntax [start:end:step], with 1D/2D slicing producing subarrays. Slices return views by default (modifications affect the original array), requiring .copy() for independent copies. Mastering shape, indexing, and slicing is essential. Practical exercises are recommended to solidify these fundamental operations.
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