Conditional case on strfind

Hi all,

I have a problem on with the strfind in matlab:

x =  
  {
      'my height is 160'
      'my height is 163'
      'my height is 167'
      'my height is 180');

feature_1 = find(~cellfun('isempty',strfind(x,'my height is 163')))

the output will be:

feature_1 =

     2

Now my problem is how do i find for "my height is > 163" ?

Thanks.

Answer 1

[dpb]

Not easily by character matching/searching. You'd need to convert the numeric value strings in the and then do the search on that. SOTOO (warning, air code, untested)...

find(cellfun(@(x) str2double(x(end-3:end)),x)>163)

[Jacky]

Thank you so much :), it works! This is checking for the last 3 numbers which are greater than 163 right? How if the x is like this:

x = {'my height is 160'
     'my height is 163'
     'my height is 167'
     'my height = "180"'};

then the last cell cannot be matched because of the quotation marks before and after the number? Any way to solve this?

Thank you.

Answer 2

[Azzi Abdelmalek]

x ={ 'my height is 160'
  'my height is 163'
  'my height is 167'
  'my height is 180'};
num=regexp(x,'[0-9]+(\.)?[0-9]?','match')
out=x(str2double([num{:}])>163)

[Jacky]

Thanks so much for your reply. I'm also using regular expression to solve this. But, if the x is like this:

x = {'my height is 1'
     'my height is 13'
     'my height is 5'
     'my height = "2"'};

A = find(~cellfun('isempty',regexp(x, 'height = "[0-5]"', 'match')));
B = find(~cellfun('isempty',regexp(x, 'height is [0-5]', 'match')));

The output is:

>> B

B =

     1
     2
     3

>> A

A =

     4

The output for B is incorrect, because 'my height is 13' is included, but this is not suppose to included as 13 is not within the range of [0-5]. What is the mistake i made in the regular expression there?

Thank you.

[Azzi Abdelmalek]

This is not my answer. don't change [0-9],

num=regexp(x,'[0-9]+(\.)?[0-9]?','match')
a=str2double([num{:}])

The result is

   1    13     5     2

Now we find the range 0-5

out=x(a>0 & a<=5 )

Answer 3

[Jos (10584)]

Approach this in two steps:

Step 1. Convert the strings to a numerical values. This step depends on how the strings are made up. If there is always one and only one value in each string, you can do something like this:

s = regexp(x,'\d+','match') 
num = str2double([s{:}])

Step 2. Use logical indexing to get the indices into x

tf = num > 2 & num <= 5 % whatever
indices = find(tf)
result = x(tf)