Re: Bug in [NSScanner scanDouble:]

[Gregory Casamento]

Doug,

Regarding where to file... you can do it on github.  That shouldn't be a problem.

I'm curious, could this be a rounding error?  Double is supposed to have a precision of 15 decimal places.

Yours, GC

On Mon, Dec 28, 2020 at 6:30 PM Douglas Simons <Doug.Simons@eggplantsoftware.com> wrote:

Hi, sorry for posting a bug report here, but I seem to have lost my credentials for accessing the bug tracker.

The scanDouble: method of NSScanner is adding a tiny fraction to the value scanned (at least on Windows).

NSScanner *scanner = [NSScanner scannerWithString:@“197319600.000000”];

double val = 0.0;

[scanner scanDouble:&val];

NSLog(@"scanDouble got: %.9f", val);

// results in val having the value 197319600.00000012

Note that NSString’s doubleValue method doesn’t have this problem, so I’m using that to work around this problem for now.

Thanks!

Doug

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Gregory Casamento
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