Cookbook Date and Time : Measure Elapsed Time

[Adamme-le-codeur-fou]

added the recipe 'Measure Elapsed Time' (uses Unix.gettimeofday)

[Copilot]

Pull request overview

This PR adds a new cookbook recipe demonstrating how to measure elapsed time in OCaml using the Unix.gettimeofday function from the standard library.

• Introduces a basic example of timing code execution
• Provides a reusable helper function for timing arbitrary operations
• Demonstrates tail-recursive functions as test cases for timing

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[Copilot]

The comment has awkward repetition of "which". Consider rephrasing to: "We use the Unix library (part of OCaml's standard library) to access Unix.gettimeofday, which gets the current time in seconds since the Unix epoch."

Suggested change

	(* We use the `Unix` library (which is part of OCaml's standard library), which provides the function `Unix.gettimeofday` to get the current time in seconds since the Unix epoch. *)
	(* We use the `Unix` library (part of OCaml's standard library) to access `Unix.gettimeofday`, which gets the current time in seconds since the Unix epoch. *)

[Copilot]

Calling Unix.gettimeofday () twice may introduce a small timing error. It's better to capture the end time in a variable first, then compute the elapsed time. This ensures the measurement is more accurate.

Suggested change

	Printf.printf "Elapsed time: %f seconds\n" (Unix.gettimeofday () -. start_time)
	(* We can also create a function that executes another function and prints the elapsed time *)
	let exec_and_print_elapsed_time f name =
	let start_time = Unix.gettimeofday () in
	let result = f () in
	Printf.printf "Elapsed time for %s: %f seconds\n" name (Unix.gettimeofday () -. start_time);
	let end_time = Unix.gettimeofday () in
	Printf.printf "Elapsed time: %f seconds\n" (end_time -. start_time)
	(* We can also create a function that executes another function and prints the elapsed time *)
	let exec_and_print_elapsed_time f name =
	let start_time = Unix.gettimeofday () in
	let result = f () in
	let end_time = Unix.gettimeofday () in
	Printf.printf "Elapsed time for %s: %f seconds\n" name (end_time -. start_time);

[Copilot]

Calling Unix.gettimeofday () twice may introduce a small timing error. It's better to capture the end time in a variable first, then compute the elapsed time. This ensures the measurement is more accurate.

Suggested change

	Printf.printf "Elapsed time: %f seconds\n" (Unix.gettimeofday () -. start_time)
	(* We can also create a function that executes another function and prints the elapsed time *)
	let exec_and_print_elapsed_time f name =
	let start_time = Unix.gettimeofday () in
	let result = f () in
	Printf.printf "Elapsed time for %s: %f seconds\n" name (Unix.gettimeofday () -. start_time);
	let end_time = Unix.gettimeofday () in
	Printf.printf "Elapsed time: %f seconds\n" (end_time -. start_time)
	(* We can also create a function that executes another function and prints the elapsed time *)
	let exec_and_print_elapsed_time f name =
	let start_time = Unix.gettimeofday () in
	let result = f () in
	let end_time = Unix.gettimeofday () in
	Printf.printf "Elapsed time for %s: %f seconds\n" name (end_time -. start_time);