How to search for specific characters within a string.

Question

Alex 2013-9-18

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/87556-how-to-search-for-specific-characters-within-a-string

评论： dpb 2013-10-1

Say I have the following files,

foo1.85e-01.mat
foo1.79e+00.mat
foo1.82e+00.mat
foo1.94e+00.mat
foo2.30e+00.mat

How can I select just the files with numbers between 1.8 and 2.0, i.e., the third and fourth files? Together the commands

flist = dir('foo1.8*e+00.mat')

and

flist = dir('foo1.9*e+00.mat')

return all the desired files. But is there a single query that will return the same files?

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

dpb 2013-9-18

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/87556-how-to-search-for-specific-characters-within-a-string#answer_97132

在 MATLAB Online 中打开

The OS wildcard search isn't flexible enough directly; I'd just return them all and then winnow the list while processing it -- sotoo

d=dir('foo*.mat');
for ix=1:length(d)
  fn=d(ix).name;
  if ~iswithin(sscanf(fn,'foo%f.mat'), 1.8, 2.0), break, end  % skip unwanted
  ...
end

where iswithin is my handy helper function

function flg=iswithin(x,lo,hi)
% returns T for values within range of input
% SYNTAX:
%  [log] = iswithin(x,lo,hi)
%      returns T for x between lo and hi values, inclusive
    flg= (x>=lo) & (x<=hi);

2 个评论
显示无隐藏无

Alex 2013-10-1

Thanks, dpb. I've implemented something similar in my code now. The sscanf function was the thing I was looking for, something that would extract numbers from a string.