System.out.println((double)(20/200)*100);
I thought it was a rounding issue initially but the issue still persists when it's a double.
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3What do you think `20/200` will return? – M A Mar 14 '19 at 13:46
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1Your cast into `double` is too late: it's already 0 by that time. – PM 77-1 Mar 14 '19 at 13:47
2 Answers
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This question is basically a duplicate, but since you seem to be on the right track, here is one slight change you can do to make this work:
System.out.println((20.0d/200)*100);
That is, make the ratio involve at least one double in the numerator or denominator. After that point, you will have a double for the quotient, and multiplying by an integer will not change that precision.
Tim Biegeleisen
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The `0d` may be omitted, `20.` is enough for java to know that it's a `double` – Lino Mar 14 '19 at 13:48
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Because 20/200 is integer divison, hence it will truncate to 0 and the whole expression will return 0.
You should change to float division and to do that is enough to transofrm one of the operands to float type (ex: 20 / 200.0).
NiVeR
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It will floor it for positive numbers, *but* will ceil it for negative numbers. The better term is *truncate*, or *discard decimal places* – Lino Mar 14 '19 at 13:49
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