Time for action - trying out floor, ceil, round, and fix

1. 1. The floor function:

octave:31> floor(1.9)
ans = 1

1. 2. The ceil function:

octave:32> ceil(1.1)
ans = 2

1. 3. The round function:

octave:33> round(1.9)
ans = 2

1. 4. The fix function:

octave:34> fix(pi)
ans = 3

What just happened?

From Command 31, we see that floor returns the largest integer which is smaller than the input argument, ceil the smallest integer that is larger than the input, round simply rounds towards to the nearest integer, and fix returns the integer part of a real number. With these definitions, we have:

octave:35> floor(-1.9)
ans = -2

The four functions will work in an element-wise fashion if the input is an array with arbitrary dimensions.

sum and prod

The functions sum and prod are also very useful. Basically they sum or multiply the elements in an array. Let us see two simple examples:

octave:36> sum([1 2; 3 4])
ans =
4 6
octave:37> prod([1 2 3 4])
ans = 24

You can also perform accumulated...