Finding dates that aren't in chronological order

[bikeknife]

Hello.

I'm working with a series of 5 dates that should be in chronological order and when they aren't I need to notify a user. I can think of a pretty ugly approach to this but would like to find something that doesn't involve an expression that looks like an essay.

Example:

The value of Date1 shouldn't be after Date2, Date3, Date4, or Date5

Date2 shouldn't be after Date3, Date4, or Date5

etc.

When a date is identified as being out of chronological order, I need to know which date it is.

I have these dates in an array of objects and was hoping to avoid using a loop as I'm already double nested and cringe at the thought of going deeper. Comparing arrays would be nice and I can add control values to the object but I'm stuck at this point.

Thanks

[ManishSolanki · Accepted solution]

Hi @bikeknife 

Here is a sample flow.

I have stored input object array in compose action:

[
{
"Date": "2024-07-12"
},
{
"Date": "2024-07-13"
},
{
"Date": "2024-07-14"
}
]

Next, add another compose action that contains object array in sorted by date. We will use sort function to sort the input array based on date property:

sort(outputs('Compose'),'Date')

Next, add "Select" action to compare input array and ideally sorted array. Using expression, we will compare each element sequentially in both compose action & thereby avoiding loop. Enter expression in 'From' parameter:

range(0,length(outputs('Compose_2')))

In Map parameter, enter 'IsMatch' as plain text in key textbox. Enter an expression in value textbox:

equals(outputs('Compose')[item()]['Date'],outputs('Compose_2')[item()]['Date'])

Now, add "Filter array" action to check if there is any non-matching element in the output of "Select" action. Pass the output of select action to 'From' parameter:

Click 'Edit in advanced mode' button on the bottom of the action & enter the below query in the textbox:

@equals(item()?['isMatch'], false)

Finally, add condition to check if input object array is in sorted order by date. If filter array returns any element that means dates are not in chronological order else dates are in chronological order. Enter an expression to check the length of output array return by filter array action:

length(body('Filter_array'))

Accordingly, add the actions in "Yes" and "No" branches as per your need:

Output:

If we tested with non sorted dates in input array object:

[
{
"Date": "2024-07-13"
},
{
"Date": "2024-07-15"
},
{
"Date": "2024-07-14"
}
]

Output will look like:

If this helps & solves your problem, please remember to give a 👍 and accept my solution as it will help others in the future.

[Chriddle · Accepted solution]

The solution for this is dependent of your definition of "being out of chronological order"😉

This will mark the items (CorrectOrder=false) whose date property is greater than that of the previous item:

Select

From

range(0, length(outputs('Compose')))

Map Date

outputs('Compose')[item()]

Map CorrectOrder

if(
	equals(item(), 0),
	true,
	greater(
		outputs('Compose')[sub(item(), 1)]['Date'],
		outputs('Compose')[item()]['Date']
	)
)

Result:

[
  {
    "Date": {
      "Date": "2024-07-15"
    },
    "CorrectOrder": true
  },
  {
    "Date": {
      "Date": "2024-07-13"
    },
    "CorrectOrder": true
  },
  {
    "Date": {
      "Date": "2024-07-14"
    },
    "CorrectOrder": false
  }
]

[ManishSolanki]

You are so smart 😎 😉