Yield the Change Between Readings

Medium ⏱ 12 min 62% acceptance ★★★★★ 4.7

Write the generator deltas(readings) yielding the difference between each consecutive pair from ANY iterable — including one-shot iterators, so you cannot index or zip the input with itself via two passes. Track the previous value as you go.

Examples

Example 1

Input

list(deltas(iter([10, 13, 11])))

Output

[3, -2]

Explanation

Works on a pure iterator: 13-10 and 11-13.

Constraints

Single pass, no indexing.
Zero or one readings yield nothing.

Topics

Iterators & Generatorspairwise

Companies

TeslaBoschHoneywell

Hints

Hint 1

Prime prev with next(it, sentinel).

Hint 2

Yield current - prev, then advance prev.

← Flatten Deeply with yield from A Generator You Can send() To →

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