NumPy NumPy参考

• 数组对象
• 常数
• 通用功能（ufunc）
• 例行程序
•    数组创建例程
•    数组操作例程
•    Binary operations
•    String operations
•          numpy.char.add
•          numpy.char.multiply
•          numpy.char.mod
•          numpy.char.capitalize
•          numpy.char.center
•          numpy.char.decode
•          numpy.char.encode
•          numpy.char.expandtabs
•          numpy.char.join
•          numpy.char.ljust
•          numpy.char.lower
•          numpy.char.lstrip
•          numpy.char.partition
•          numpy.char.replace
•          numpy.char.rjust
•          numpy.char.rpartition
•          numpy.char.rsplit
•          numpy.char.rstrip
•          numpy.char.split
•          numpy.char.splitlines
•          numpy.char.strip
•          numpy.char.swapcase
•          numpy.char.title
•          numpy.char.translate
•          numpy.char.upper
•          numpy.char.zfill
•          numpy.char.equal
•          numpy.char.not_equal
•          numpy.char.greater_equal
•          numpy.char.less_equal
•          numpy.char.greater
•          numpy.char.less
•          numpy.char.compare_chararrays
•          numpy.char.count
•          numpy.char.endswith
•          numpy.char.find
•          numpy.char.index
•          numpy.char.isalpha
•          numpy.char.isalnum
•          numpy.char.isdecimal
•          numpy.char.isdigit
•          numpy.char.islower
•          numpy.char.isnumeric
•          numpy.char.isspace
•          numpy.char.istitle
•          numpy.char.isupper
•          numpy.char.rfind
•          numpy.char.rindex
•          numpy.char.startswith
•          numpy.char.str_len
•          numpy.char.array
•          numpy.char.asarray
•          numpy.char.chararray
•    C-Types Foreign Function Interface (numpy.ctypeslib)
•    Datetime Support Functions
•    Data type routines
•    Optionally Scipy-accelerated routines (numpy.dual)
•    Mathematical functions with automatic domain (numpy.emath)
•    Floating point error handling
•    Discrete Fourier Transform (numpy.fft)
•    Financial functions
•    Functional programming
•    NumPy-specific help functions
•    Indexing routines
•    输入输出
•    线性代数（numpy.linalg）
•    逻辑功能
•    Mathematical functions
•    Matrix library (numpy.matlib)
•    Miscellaneous routines
•    Padding Arrays
•    Polynomials
•    Random sampling (numpy.random)
•    Set routines
•    Sorting, searching, and counting
•    Statistics
•    Test Support (numpy.testing)
•    Window functions
• Packaging (numpy.distutils)
• NumPy Distutils - Users Guide
• NumPy C-API
• NumPy内部
• NumPy和SWIG

numpy.char.lower(a)¶

Return an array with the elements converted to lowercase.

Call str.lower element-wise.

For 8-bit strings, this method is locale-dependent.

Parameters

aarray_like, {str, unicode}

Input array.

Returns

outndarray, {str, unicode}

Output array of str or unicode, depending on input type

See also

str.lower

Examples

>>> c = np.array(['A1B C', '1BCA', 'BCA1']); c
array(['A1B C', '1BCA', 'BCA1'], dtype='<U5')
>>> np.char.lower(c)
array(['a1b c', '1bca', 'bca1'], dtype='<U5')