# Perform an action if N is within a pre-determined range

I have a number generator/counter that will output increasingly higher values ranging from `1 to 1,000`.

Once it reaches `1,000`, the count is reset and restarts.

The total numbers generated between `1--1,000` is variable and random.

The delta between numbers is variable and random.

Example:

`````` 1, 45, 120, 300, 590, 700, 750, 967
3,  4, 212, 400, 660, 800, 850, 901, 967, 998
50, 90, 121, 603, 780, 833, 890
``````

I need to trigger an action every time the counter passes a certain pre-determined threshold. For example, if the threshold were 100th, that would mean if a new hundred-handle is generated, that would trigger the action.

``````100 -> action
120
350 -> action
355
378
490 -> action
600 -> action
601
677
905 -> action
``````

I’m blocked in how to resolve this. I though of using the modulus operator but that won’t suffice as the generated numbers are unpredictable and their divisibility cannot be pre-determined.

Any ideas how to accomplish this task? TIA

### >Solution :

You can use floor division by your step, then compute the successive differences to identify the groups:

``````group = a//100
# array([0, 0, 1, 3, 5, 7, 7, 9, 0, 0, 2, 4, 6, 8, 8, 9, 9, 9, 0, 0, 1, 6,
#        7, 8, 8])

actions = np.r_[True, np.diff(group)!=0]
# array([ True, False,  True,  True,  True,  True, False,  True,  True,
#        False,  True,  True,  True,  True, False,  True, False, False,
#         True, False,  True,  True,  True,  True, False])
``````

As a single array:

``````np.vstack([a, actions]).T

array([[  1,   1],
[ 45,   0],
[120,   1],
[300,   1],
[590,   1],
[700,   1],
[750,   0],
[967,   1],
[  3,   1],
[  4,   0],
[212,   1],
[400,   1],
[660,   1],
[800,   1],
[850,   0],
[901,   1],
[967,   0],
[998,   0],
[ 50,   1],
[ 90,   0],
[121,   1],
[603,   1],
[780,   1],
[833,   1],
[890,   0]])
``````