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<== Date ==> <== Thread ==>

Subject: FLOOR function in EPICS CALC error
From: <[email protected]>
To: <[email protected]>
Date: Fri, 11 Nov 2016 20:08:59 +0000

Hi,

 

I am seeing what I think may be a rounding error in the FLOOR function and I was wondering if others had seen this. I replaced the variables in my code with actual values to reproduce the problem. I am using EPICS R3.14.12.5 with Scientific Linux 7. I also tried it with the same version of EPICS running on Linux Mint

 

In Calc records, just using an empty Calc record and putting the values in by hand:

 

record(calc,"DLY:FSTEP")

{

 field(CALC,"6.1-0.2/0.01")

}

 

 

6.1-0.2/0.01 gives 590 as it should

 

However:

FLOOR((6.1-0.2)/0.01)

 

Gives me 589

 

If I write it as follows:

FLOOR((6.1-0.2)*(1/0.01))

 

I again get 590 (as it should be)

 

I wondered if this was my install or if this has been seen before. It only seems to happen for random values.

 

Best regards,

 

Rory Clarke


Replies:
RE: FLOOR function in EPICS CALC error Mooney, Tim M.

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