Function used in binary search:
The function below implements this binary search algorithm. It receives two arguments: the sorted vector and a key (on the other hand, the function could sort the vector). The value of low and high are initialized to the first and last indices in the vector. The outind that is the output argument is initialized to -1 that is the value which the function will return when the key is not found. It loops until either low is greater than high, or til the key is found.
The illustrations of calling this function are as shown here:
>> vec = randint(1,7, [1 30])
vec =
2 11 25 1 5 7 6
>> svec = sort(vec)
svec =
1 2 5 6 7 11 25
>> binsearch(svec, 4)
ans =
-1
>> binsearch(svec, 25)
7
>> binsearch(svec, 5)
3