Sorting data from text file

We have to take data from a .txt file and create a for loop that searches through the data and then finds the lowest value. It then displays that value and searches for the next highest number.

What I have so far:

[Time Height] = textread('HW4_CurveFitData.txt','%f %f','delimiter',',');

t = [];

h = [];

CurrentValue = -inf;

while length(t) < length(Time)

    for k = 1 : length(Time)

        if Time(1) > CurrentValue

        end
    end
    t(end+1)= CurrentValue
end

 I'm getting caught up in the middle part where you have to search through the data.