和上的区别不是很大decode
, but astype
有效(并且可以应用于整个数组而不是每个字符串)。但只要需要,较长的阵列就会保留下来。
In [538]: x=my_array.astype('U');"Mary has an {} and a {}".format(x[0],x[1])
Out[538]: 'Mary has an apple and a pear'
我在其中找不到任何内容format
强制“b”少格式化的语法。
https://stackoverflow.com/a/19864787/901925 https://stackoverflow.com/a/19864787/901925- 展示如何自定义 Formatter 类,更改format_field
方法。我尝试了类似的东西convert_field
方法。但调用语法还是很乱。
In [562]: def makeU(astr):
return astr.decode('utf-8')
.....:
In [563]: class MyFormatter(string.Formatter):
def convert_field(self, value, conversion):
if 'q'== conversion:
return makeU(value)
else:
return super(MyFormatter, self).convert_field(value, conversion)
.....:
In [564]: MyFormatter().format("Mary has an {!q} and a {!q}",my_array[0],my_array[1])
Out[564]: 'Mary has an apple and a pear'
进行此格式化的其他几种方法:
In [642]: "Mary has an {1} and a {0} or {1}".format(*my_array.astype('U'))
Out[642]: 'Mary has an pear and a apple or pear'
这会(即时)转换数组并将其传递给format
作为一个列表。如果数组已经是 unicode,它也可以工作:
In [643]: "Mary has an {1} and a {0} or {1}".format(*uarray.astype('U'))
Out[643]: 'Mary has an pear and a apple or pear'
np.char
具有将字符串函数应用于字符数组元素的函数。有了这个decode
可以应用于整个数组:
In [644]: "Mary has a {1} and an {0}".format(*np.char.decode(my_array))
Out[644]: 'Mary has a pear and an apple'
(如果数组已经是 unicode,则这不起作用)。
如果你对字符串数组做了很多工作,np.char
值得研究。