Javier, Thanks for your comments and details provided in return email, I also know that division by zero is undetermined / infinity. I just put an example to explain, how we could tackle this problem. Best regards
Rehan Wyne MIT On Tuesday, September 16, 2014 11:38 PM, Javier Valencia <[email protected]> wrote: I did not receive my response either… ================= Rehan, You provide a viable and workable and quite clever solution to the problem. However, technically a division by zero IS NOT zero. Most mathematical processes interpret a division by zero as having an indeterminate result; the IEEE Standard for Floating-Point Arithmetic (IEEE 754) indicates that zero can have a sign (+ or -) and the result will be either positive or negative INFINITY depending on the sign assigned to the zero divisor. Maybe assigning a zero in this particular case would work, but in some circumstances it could be misleading; I would personally assign a NULL value to operations that include division by zero since it really is an undetermined value. Just my 2 cents. ================= Javier, Javier Valencia, PE O: 913-829-0888 H: 913-397-9605 C: 913-915-3137 From:[email protected] [mailto:[email protected]] On Behalf Of rehan wyne Sent: Tuesday, September 16, 2014 12:23 PM To: RBASE-L Mailing List Subject: [RBASE-L] - Re: Divide by Zero I am reproducing my last email because I doubt that it may not be received by any one or Rbase list. Quote "Dennis, If you check the divisor first, in your select statement then you don't need to create any view and it will be efficient too regardless how R:base is processing Select Statement. As explained below: Let Y is dividend and X is divisor. Select Y,X,(ifeq(X,0,0,(Y/X))) from example Here we explicitly put the division result to ZERO, as it should be. Regards Rehan Wyne MIT" unquote On Thursday, September 11, 2014 9:18 PM, "Hodges, Dennis" <[email protected]> wrote: I’m getting a divide by zero from the following select statement. The values for tothrs and activity.standard are all positive real numbers, no zeros or nulls. Does anyone have a clue as to why I’m getting this error. Somehow tothrs/activity.standard is evaluating to 0 as shown below. Select t3t.*,activity.activity,activity.unitmeas,activity.standard,(tothrs/activity.standard) AS standardunits,(units/(tothrs/activity.standard)*100) AS expectedunits FROM t3t, activity WHERE t3t.activity EQ activity.activity and activity.standard <> 0 Tothrs Units Activity UnitMEas Standard StandardUnits 1.5 1.5 033 Manh 1 0 2 2 032 Manh 1 0 6.5 6.5 941 Manh 1 0 4 4 520 Unit 0.83 0 6 11 520 Unit 0.83 0 10 20 520 Unit 0.83 0 3 3 028 Manh 1 0 5 130 526 LnFt 0.25 0 10 14 520 Unit 0.83 0 Dennis Hodges Maintenance Management Manager FDOT Office of Maintenance MS #52 PH: (850) 410-5635 FAX: (850) 410-5511 [email protected] As far as we know, our computer has never had an undetected error. Please note: e-mail may be subject to public disclosure.
