Identify a number in a string

Question

Omphemetse Moeng 2020-10-11

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/610401-identify-a-number-in-a-string

评论： Omphemetse Moeng 2020-10-11

Hi all, I would like to know how to identify and extract a number or digit from a string or text, so if I have Ans = ['2.66 meters in the front of the mirror']; I would only like to identify and extract the double, this should be a general thing and not only specific to the 2.66. Please help

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

madhan ravi 2020-10-11

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/610401-identify-a-number-in-a-string#answer_510596

在 MATLAB Online 中打开

Wanted = str2double(regexp(Ans, '(+|-)?(\d+)?\.?\d*', 'match'))

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Omphemetse Moeng 2020-10-11

Thank you for this, it works.

请先登录，再进行评论。

Answer 2

Ameer Hamza 2020-10-11

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/610401-identify-a-number-in-a-string#answer_510591

编辑：Ameer Hamza 2020-10-11

在 MATLAB Online 中打开

Try sscanf()

str = '2.66 meters in the front of the mirror';
nums = sscanf(str, '%f');

Result

>> nums
nums =
    2.6600

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Omphemetse Moeng 2020-10-11

Thank you, this only works if the number is placed first, so generally should its position in the string change it does not work anymore, I then get 0x0 double. Is there a more general way to this?

请先登录，再进行评论。