Why Will a Range Not Work When Descending

Why will a Range not work when descending?

The easiest way to do that is use downto

5.downto(1) do |i| puts i end

Print a list in reverse order with range()?

use reversed() function:

reversed(range(10))

It's much more meaningful.

Update:

If you want it to be a list (as btk pointed out):

list(reversed(range(10)))

Update:

If you want to use only range to achieve the same result, you can use all its parameters. range(start, stop, step)

For example, to generate a list [5,4,3,2,1,0], you can use the following:

range(5, -1, -1)

It may be less intuitive but as the comments mention, this is more efficient and the right usage of range for reversed list.

Getting a descending range sequence in Ruby

Try this:

5.downto(1).to_a # => [5, 4, 3, 2, 1]

Of course, there's a corresponding #upto. If you want steps, you can do this:

1.step(10, 2).to_a # => [1, 3, 5, 7, 9]
10.step(1, -2).to_a # => [10, 8, 6, 4, 2]

Why are 2 kotlin descending IntRanges equal?

The documentation for the IntRange.isEmpty says:

The range is empty if its start value is greater than the end value.

Therefore, both 10..1 and 9..1 will be empty ranges, and empty ranges are considered equal in the current implementation of equals.

If you want a sequence that goes from 10 down to 1, you might be looking for the downTo infix function instead. Note that this gives you a more general IntProgression, not an IntRange.

val from10To1 = 10 downTo 1

How spark RangeBetween works with Descending Order?

It's not well documented but when using range (or value-based) frames the ascending and descending order affects the determination of the values that are included in the frame.

Let's take the example you provided:

RANGE BETWEEN 1 PRECEDING AND CURRENT ROW

Depending on the order by direction, 1 PRECEDING means:

• current_row_value - 1 if ASC
• current_row_value + 1 if DESC

Consider the row with value 1 in partition b.

• With the descending order, the frame includes :

  (current_value and all preceding values where x = current_value + 1) = (1, 2)

• With the ascending order, the frame includes:

  (current_value and all preceding values where x = current_value - 1) = (1)

PS: using rangeBetween(-1, Window.currentRow) with desc ordering is just equivalent to rangeBetween(Window.currentRow, 1) with asc ordering.

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