python numpy.shape 和 numpy.reshape函数

妖狐艹你老母 2022-09-25 14:26 241阅读 0赞

[http://blog.csdn.net/u012005313/article/details/49383551][http_blog.csdn.net_u012005313_article_details_49383551]

导入numpy模块

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1.  **from** numpy **import** \*  
2.  **import** numpy as np

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numpy.shape：

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1.  help(shape)

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输入参数：类似数组（比如列表，元组）等，或是数组

返回：一个整型数字的元组，元组中的每个元素表示相应的数组每一维的长度

类似数组

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1.  \#一维列表  
2.  L=range(5)  
3.  shape(L)  
4.  \#二维列表  
5.  L=\[\[1,2,3\],\[4,5,6\]\]  
6.  shape(L)

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数组：

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1.  \#一维数组  
2.  arr=array(range(5))  
3.  shape(arr)  
4.  \#二维数组  
5.  arr=array(\[\[1,2,3\], \[4,5,6\]\])  
6.  shape(arr)

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numpy.reshape：

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1.  help(reshape)

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函数功能：给予数组一个新的形状，而不改变它的数据

输入参数：

a：将要被重塑的类数组或数组

newshape：整数值或整数元组。新的形状应该兼容于原始形状。**如果是一个整数值，表示一个一维数组的长度；如果是元组，一个元素值可以为-1，此时该元素值表示为指定，此时会从数组的长度和剩余的维度中推断出**

order：可选（忽略）

返回：一个新的形状的数组

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1.  a=array(\[\[1,2,3\],\[4,5,6\]\])  
2.  reshape(a, 6)

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1.  reshape(a, (3, -1)) \#为指定的值将被推断出为2

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[http_blog.csdn.net_u012005313_article_details_49383551]: http://blog.csdn.net/u012005313/article/details/49383551
[view plain]: http://blog.csdn.net/u012005313/article/details/49383551#
[Center]: /images/20220717/3831a17789264b719625c17f1e260b15.png
[Center 1]: /images/20220717/d5d134433a6349c9a8212f7fd0c02fc8.png
[Center 2]: /images/20220717/063bb5ba754f4c23a772e8eb1e438e6f.png
[Center 3]: /images/20220717/7615bc24a1ee4ee8bc4b4f7f3f74831b.png
[Center 4]: /images/20220717/6d366749f5a3448ca543e03fe59932f6.png
[Center 5]: /images/20220717/e82f76f329b5492b8f7c5556945e6d2f.png