How Can I count the ascending runs in array ?

if I have an array such as

x=[1 2 3 2 1 2 4 5]

I would generate a binary array for binary search

binaryarray= [1 1 1 0 0 1 1 1]

in binaryarry i would sign 1 along with ascending runs while 0 along with descending runs.

[KSSV]

diff shall be useful..read about it.

[Willim]

I used it

v=diff(x)

v(v>=0)=1

v(v<0)=0

but it give me wrong result for larger x

Answer 1

[Stephen23]

As KSSV wrote, you might find diff useful:

>> y = y([1,1:end])
y =
  1  1  1  0  0  1  1  1