# Extract values within interquartile range in array

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Vlatko Milic on 31 Oct 2018
Commented: Sesilia Iileka on 6 Mar 2019
Hi,
I want to extract values within an interquartile range in an array. Let say that the array looks as follows: v= [1 2 3 4 5 6 ......95 96 97 98 99]. The interquartile range is 25 and 75. How can I extract the array values from 25 to 75 to a new array? If possible, can I select other ranges than bottom and top 25%?
Thanks!

the cyclist on 31 Oct 2018
Edited: the cyclist on 31 Oct 2018
Use the quantile command to get whichever quantiles you want.
Then extract using logical indexing (as described on this documentation page).
v = 1:99;
q = quantile(v,[0.25 0.75])
v2 = v(v>q(1) & v<q(2))
Sesilia Iileka on 6 Mar 2019
Hi i want kind of the same thing but from a loop
like this:
for i = length(x)
xy = find(u==i | u>i & u4<(i+1)); #xy should find indices of u within that range i.e u(i)>=i<u(i+1)
N(i) = length(xy) #giving me counts of i
end
but then, the last iteration (last value of i) will be wrong by this expression.
how do i correct this please?
Thanks a lot

madhan ravi on 31 Oct 2018
Edited: madhan ravi on 31 Oct 2018
v=1:100;
new_array = v(v >=25 & v<=75) %values between 25 to 75
new_array1 = v(v<25 | v>75) % values less than 25 and greater than 75
Sesilia Iileka on 6 Mar 2019
Hi i want kind of the same thing but from a loop
like this:
for i = length(x)
xy = find(u==i | u>i & u4<(i+1)); #xy should find indices of u within that range i.e u(i)>=i<u(i+1)
N(i) = length(xy) #giving me counts of i
end
but then, the last iteration (last value of i) will be wrong by this expression.
how do i correct this please?
Thanks a lot