Talk:Greatest common divisor: Difference between revisions
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A few programs would attempt to divide by zero if the 2nd argument is 0 (zero). |
A few programs would attempt to divide by zero if the 2nd argument is 0 (zero). |
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<br> In that special case, the absolute value of the first argument should be returned. |
<br> In that special case, the absolute value of the first argument should be returned. -- [[User:Gerard Schildberger|Gerard Schildberger]] 15:39, 17 August 2012 (UTC) |
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::unless it is 0 --[[User:Walterpachl|Walterpachl]] 12:40, 17 August 2012 (UTC) |
::unless it is 0 --[[User:Walterpachl|Walterpachl]] 12:40, 17 August 2012 (UTC) |
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::: The special case of '''gcd(0,0)''' is usually defined to be '''0''', but some authors consider it to be '''undefined'''. When implementing the REXX version 1 example, the first definition (0) was chosen. So, for that case, '''|0| = 0'''. -- [[User:Gerard Schildberger|Gerard Schildberger]] 15:39, 17 August 2012 (UTC) |
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== REXX Version 1 == |
== REXX Version 1 == |
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Revision as of 15:39, 17 August 2012
errors in programs
A few programs would attempt to divide by zero if the 2nd argument is 0 (zero).
In that special case, the absolute value of the first argument should be returned. -- Gerard Schildberger 15:39, 17 August 2012 (UTC)
- unless it is 0 --Walterpachl 12:40, 17 August 2012 (UTC)
- The special case of gcd(0,0) is usually defined to be 0, but some authors consider it to be undefined. When implementing the REXX version 1 example, the first definition (0) was chosen. So, for that case, |0| = 0. -- Gerard Schildberger 15:39, 17 August 2012 (UTC)
A number of examples don't show the results if either argument is negative. -- Gerard Schildberger 15:39, 17 August 2012 (UTC)
REXX Version 1
These results seem to be wrong:
- the GCD of 14 and 0 and 7 is 14 should be 7
- the GCD of 0 and 7 is 0 should be 7
- the GCD of 0 and 0 is 0 should be ???
correct:
- the GCD of 7 and 0 is 7
--Walterpachl 12:06, 17 August 2012 (UTC)
PL/I
should return a positive integer
- and take care of gcd/0,0)
--Walterpachl 12:39, 17 August 2012 (UTC)