Counting the number of elements in a table.

I have a table that is 500x4. The fourth row contains the numerical values. What I want to do is use a code to count the variables in a certain range. For example, I want to know how many values in that row are greater than or equal to 1, but less than or equal to 6. I tried the count command, but it didn't do anything. Any help would be greatly appreciated.

Answer 1

[Image Analyst]

Try this:

% Build sample table:
m = 10 * rand(500,4);
t = table(m(:,1), m(:,2), m(:,3), m(:,4));
% Now that we have a table, we can begin.
% Extract 4th row
row4 = t{4, :}  % NOTE: braces, NOT parentheses since it's a table, not a double array.
inRange = row4 >= 1 & row4 <= 6
numberInRange = sum(inRange)

[Matthew Olivo]

Thank you.

[Peter Perkins]

To do this on every row, try this:

>> m = 10 * rand(5,4);
>> t = array2table(m)
t =
  5×4 table
      m1        m2        m3        m4  
    ______    ______    ______    ______
    4.1948    3.2883     7.022    9.9833
    2.9618    9.7814    1.4663     3.996
    5.8959    9.5053    6.5502    8.9666
    8.3438    8.1493    5.1842    6.5132
    6.4523    1.6561    1.6406    8.2775
>> inRange = sum((t.Variables >= 1) & (t.Variables <= 6),2)
inRange =
     2
     3
     1
     1
     2

rowfun is also a candidate here.

Prior to R2016b, you'll have to substitute t{:,:} for t.Variables.