JDK-8283143: Use minimal-length literals to initialize PI and E constants

[jddarcy]

Depending on the range of the number line, a double value has between 15 and 17 digits of decimal precision. The literals used to initialize Math.PI and Math.E have several digits more precision than that maximum.

That is potentially confusing to readers of the code and the minimum length strings to exactly represent the value in question should be used instead.

---

Progress

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Issue

• JDK-8283143: Use minimal-length literals to initialize PI and E constants

Reviewers

• Stuart Marks (@stuart-marks - Reviewer) ⚠️ Review applies to 3bf9de9

Reviewing

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[openjdk]

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[mlbridge]

Webrevs

• 01: Full - Incremental (f4c0e63e)
• 00: Full (3bf9de9f)

[stuart-marks]

I've verified that the shorter literals result in the same double bit pattern.

[openjdk]

@jddarcy This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8283143: Use minimal-length literals to initialize PI and E constants

Reviewed-by: smarks

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 21 new commits pushed to the master branch:

• f43ffe2: 8282633: jarsigner output does not explain why an EC key is disabled if its curve has been disabled
• 4de7201: 8283122: [AIX, s390] UnsafeCopyMemory 'Mismatched' Tests Fail on Big Endian Systems
• 2cddf3f: 8282887: Potential memory leak in sun.util.locale.provider.HostLocaleProviderAdapterImpl.getNumberPattern() on Windows
• 710653c: 8254786: java/net/httpclient/CancelRequestTest.java failing intermittently
• 34d4ffc: 8279317: compiler/jvmci/compilerToVM/DisassembleCodeBlobTest.java assumes immutable code
• 6013d09: 8268866: Javascript when used in an iframe cannot display search results
• 5ba5e21: 8282214: Upgrade JQuery to version 3.6.0
• a244051: 8283062: Uninitialized warnings in libgtest with GCC 11.2
• 5bf6a7f: 8282691: add jdb "-R" option for passing any argument to the launched debuggee process
• f66070b: 8282577: ICC_Profile.setData(int, byte[]) invalidates the profile
• ... and 11 more: https://git.openjdk.java.net/jdk/compare/5c408c1410e15087f735a815b7edc716d514b1b3...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[mlbridge]

Mailing list message from Raffaello Giulietti on core-libs-dev:

The new decimal literals have indeed the minimal length required to
recover the doubles closest to the true mathematical values.

Raffaello

On 3/15/22 02:43, Joe Darcy wrote:

[jddarcy]

/integrate

[openjdk]

Going to push as commit 671b6ef.
Since your change was applied there have been 21 commits pushed to the master branch:

• f43ffe2: 8282633: jarsigner output does not explain why an EC key is disabled if its curve has been disabled
• 4de7201: 8283122: [AIX, s390] UnsafeCopyMemory 'Mismatched' Tests Fail on Big Endian Systems
• 2cddf3f: 8282887: Potential memory leak in sun.util.locale.provider.HostLocaleProviderAdapterImpl.getNumberPattern() on Windows
• 710653c: 8254786: java/net/httpclient/CancelRequestTest.java failing intermittently
• 34d4ffc: 8279317: compiler/jvmci/compilerToVM/DisassembleCodeBlobTest.java assumes immutable code
• 6013d09: 8268866: Javascript when used in an iframe cannot display search results
• 5ba5e21: 8282214: Upgrade JQuery to version 3.6.0
• a244051: 8283062: Uninitialized warnings in libgtest with GCC 11.2
• 5bf6a7f: 8282691: add jdb "-R" option for passing any argument to the launched debuggee process
• f66070b: 8282577: ICC_Profile.setData(int, byte[]) invalidates the profile
• ... and 11 more: https://git.openjdk.java.net/jdk/compare/5c408c1410e15087f735a815b7edc716d514b1b3...master

Your commit was automatically rebased without conflicts.

[openjdk]

@jddarcy Pushed as commit 671b6ef.

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