matlab中字符串分割以及将工作区的变量写入txt文本中

一字符串分割

matlab中最常用的字符串分割函数有两个，都比较好用，分别是strsplit和strtok。

1 strsplit函数

假设需要分割的字符串为str，直接使用 strsplit(str) 就可以分割，默认按空白字符分割，分割后的字符组成元胞数组。

>> str = \'hello world, I am a student!\'

str =

hello world, I am a student!

>> s = strsplit(str);
>> s

s =

  1×6 cell 数组

    \'hello\'    \'world,\'    \'I\'    \'am\'    \'a\'    \'student!\'

>> s{1,1}

ans =

hello

>> s{1,2}

ans =

world,

>>

strsplit的第二个参数可以是分割字符，比如用\',\'或者\'.\'或者\'-\'等进行字符串的分割，第二个参数甚至可以是包含多个分割字符的元胞数组，如下

>> str = \'With,the,development,of,society.people-have-higher-requirements-for-image-quality\'

str =

With,the,development,of,society.people-have-higher-requirements-for-image-quality

>> s1 = strsplit(str,\',\')

s1 =

  1×5 cell 数组

    \'With\'    \'the\'    \'development\'    \'of\'    \'society.people-have-…\'

>> s1{1,5}

ans =

society.people-have-higher-requirements-for-image-quality

>> s2 = strsplit(str,\'-\')

s2 =

  1×7 cell 数组

    \'With,the,developm…\'    \'have\'    \'higher\'    \'requirements\'    \'for\'    \'image\'    \'quality\'

>> s3 = strsplit(str,\'.\')

s3 =

  1×2 cell 数组

    \'With,the,development,of,society\'    \'people-have-higher-requirements-for-image-quality\'

>> s4 = strsplit(str,{\',\',\'.\',\'-\'})

s4 =

  1×12 cell 数组

  1 至 11 列

    \'With\'    \'the\'    \'development\'    \'of\'    \'society\'    \'people\'    \'have\'    \'higher\'    \'requirements\'    \'for\'    \'image\'

  12 列

    \'quality\'

>>

strsplit=最多可以有两个返回值，第二个返回值是匹配到的分割字符。

[s1,s2] = strsplit(str,\'.\')

s1 =

  1×2 cell 数组

    \'With,the,development,of,society\'    \'people-have-higher-requirements-for-image-quality\'


s2 =

  cell

    \'.\'

>> [s1,s2] = strsplit(str,\',\')

s1 =

  1×5 cell 数组

    \'With\'    \'the\'    \'development\'    \'of\'    \'society.people-have…\'


s2 =

  1×4 cell 数组

    \',\'    \',\'    \',\'    \',\'

>> [s1,s2,s3] = strsplit(str,\',\')
错误使用 strsplit
输出参数太多。

strsplit还可以有参数\'DelimiterType\'，当值为\'RegularExpression\'时，将分隔字符串按照正则表达式理解。

>> str = \'ab1cd2ef3gh4ij5kl6mn7.\'

str =

ab1cd2ef3gh4ij5kl6mn7.

>> s = strsplit(str,\'[0-9]\',\'DelimiterType\',\'RegularExpression\')

s =

  1×8 cell 数组

    \'ab\'    \'cd\'    \'ef\'    \'gh\'    \'ij\'    \'kl\'    \'mn\'    \'.\'

>> [s1,s2] = strsplit(str,\'[0-9]\',\'DelimiterType\',\'RegularExpression\')

s1 =

  1×8 cell 数组

    \'ab\'    \'cd\'    \'ef\'    \'gh\'    \'ij\'    \'kl\'    \'mn\'    \'.\'


s2 =

  1×7 cell 数组

    \'1\'    \'2\'    \'3\'    \'4\'    \'5\'    \'6\'    \'7\'

>>

2 strtok函数

strtok一般只分成两部分，默认会在从头开始遇到的第一个空格/tab/换行符处断开，也可以指定分割字符。

>>  str = \'hello world, i am a student\'

str =

hello world, i am a student

>> s1 = strtok(str)

s1 =

hello

>> s2 = strtok(str,\',\')

s2 =

hello world

strtok可以有两个返回值，第一个是分割后的前一部分，第二个是分割后的剩余部分（包括分割字符）。

>> [s3 s4] = strtok(str)

s3 =

hello


s4 =

 world, i am a student

>> [s3 s4] = strtok(str,\',\')

s3 =

hello world


s4 =

, i am a student

strtok的输入也可以是元胞数组，返回的两个返回值也是对应的元胞数组。

>> str = {\'hello world\';\'good job\'}

str =

  2×1 cell 数组

    \'hello world\'
    \'good job\'

>> [s1 s2] = strtok(str)

s1 =

  2×1 cell 数组

    \'hello\'
    \'good\'


s2 =

  2×1 cell 数组

    \' world\'
    \' job\'

>>