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StringTake

Usage

StringTake["string", n] 返回由"string"中前 n个字符构成的字符串.
StringTake["string", -n] 返回由"string"中后 n个字符构成的字符串.
StringTake["string",  n ] 返回"string"中第 n个字符.
StringTake["string",  m, n ] 给出"string"中从mn位置的字符构成的字符串.


Notes

StringTake 使用标准的序列指定 (参见 A.3.5节).
• 例如: StringTake["abcdefg", 3]LongRightArrow .
StringTake["string",  m, n, s ] 以步长 s返回从mn位置的字符.
• 参见 Mathematica 全书: 2.7.2节.
• 同时参见: Take, StringDrop, StringPosition.
Further Examples

This takes  characters starting from the end of the string.

In[1]:=  

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This takes the character at position 5.

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This takes the characters  through  .

In[3]:=  

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This takes characters  through  in steps of  .

In[4]:=  

Out[4]=