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Re: Unexpected result using floor() function - Mailing list pgsql-general

From Vick Khera
Subject Re: Unexpected result using floor() function
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Msg-id CALd+dccuPH4hMibEngNh2UKfm1pw8bbe8iKNT+-dAg0oc7Yn9Q@mail.gmail.com
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In response to Unexpected result using floor() function  ("Frank Millman" <frank@chagford.com>)
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100 is an integer
 power(10,2) is a double precision.

Try this one:

SELECT floor(4.725 * 100::double precision + 0.5);




On Mon, Mar 14, 2016 at 10:11 AM, Frank Millman <frank@chagford.com> wrote:
Hi all
 
I am running PostgreSQL 9.4.4 on Fedora 22.
 
SELECT floor(4.725 * 100 + 0.5) returns 473, which is what I expected.
 
SELECT floor(4.725 * power(10, 2) + 0.5) returns 472, which I find surprising.
 
Please can someone explain the anomaly.
 
Thanks
 
Frank Millman
 

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