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last zero was also a number
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Peter B.
Peter B.
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This example reveals a rounding error under Commodore BASIC V2.0:

  A=0.3:B=0.6:IF A+B<>0.9 THEN PRINT A+B-0.9

Running this on a C64 yields a difference of 2.32830644e-10. Other pairs that fail are 0.4+0.5, 0.6+0.1 and 0.8+0.1. Please note that also the order in which the numbers are summed up affects the result. 0.6+0.1-0.7 yields a difference, while 0.1+0.6-0.7 results to 00.

This example reveals a rounding error under Commodore BASIC V2.0:

  A=0.3:B=0.6:IF A+B<>0.9 THEN PRINT A+B-0.9

Running this on a C64 yields a difference of 2.32830644e-10. Other pairs that fail are 0.4+0.5, 0.6+0.1 and 0.8+0.1. Please note that also the order in which the numbers are summed up affects the result. 0.6+0.1-0.7 yields a difference, while 0.1+0.6-0.7 results to 0.

This example reveals a rounding error under Commodore BASIC V2.0:

  A=0.3:B=0.6:IF A+B<>0.9 THEN PRINT A+B-0.9

Running this on a C64 yields a difference of 2.32830644e-10. Other pairs that fail are 0.4+0.5, 0.6+0.1 and 0.8+0.1. Please note that also the order in which the numbers are summed up affects the result. 0.6+0.1-0.7 yields a difference, while 0.1+0.6-0.7 results to 0.

Source Link
Peter B.
Peter B.
  • 4.5k
  • 16
  • 38

This example reveals a rounding error under Commodore BASIC V2.0:

  A=0.3:B=0.6:IF A+B<>0.9 THEN PRINT A+B-0.9

Running this on a C64 yields a difference of 2.32830644e-10. Other pairs that fail are 0.4+0.5, 0.6+0.1 and 0.8+0.1. Please note that also the order in which the numbers are summed up affects the result. 0.6+0.1-0.7 yields a difference, while 0.1+0.6-0.7 results to 0.