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+--- Thread: double to 2^53 (/showthread.php?tid=1657)
double to 2^53 - Jack - 05-03-2023
Ok, I know that the size of the mantissa of double is 53 bits, see if you can guess what values will be printed by this snippet
Code: (Select All)
Dim As Double x
x = 9007199254740992 ' 2^53
Print x
x = x + 1#
Print x
x = x + 1#
Print x
Print "================="
x = 9007199254740998
Print x
x = x + 1#
Print x
x = x + 1#
Print x
Print "================="
x = 9999999999999998
Print x
x = x + 1#
Print xRE: double to 2^53 - SMcNeill - 05-03-2023
53 bits isn't 2 ^ 53.
For example: 2 bits has a limit of 3 (&H11). 8 bits has a limit of 255 (&H11111111).
The limit is number of bits ^ 2 - 1. (n ^ 2 - 1)
RE: double to 2^53 - Jack - 05-03-2023
hello SMcNeil
I think that you made typo, The limit is number of bits ^ 2 - 1. (n ^ 2 - 1)
yo probably meant "The limit of number is 2^bits - 1. (2^n - 1)" or something like that
RE: double to 2^53 - SMcNeill - 05-03-2023
Aye. Sorry. 2 ^ n - 1. I'm trying to get over Covid again, so my brain is half broken atm. Apologies.
RE: double to 2^53 - Jack - 05-03-2023
I hope that you get well soon
