php - why does floor round down a integer? -

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Why I am confused as: 

  Echo log 10 (238328) / Log 10 (62);

Results in 3

but 

  echo floor (log 10 (238328) / log 10 (62));

Results in 2

I know that the floor is round, but I thought it was only for decimal numbers.

How can I get answers 3 of the latter statements are still going round normally? PHP uses dual-precise floating point numbers; the results of two logarithm can not be perfectly represented, so the result of sharing them is

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Not accurate. The results you received are close, but slightly less than 3. When it is formatted with echo , it becomes round on 3. floor , still returns 2.

You can take advantage of this fact to avoid disqualification from the log (x, b) / log (y, b) log (x, y) (for any base b ). Instead, instead of giving you the expression log (238328, 62) , whose exact point of 3 is the point of the result (correct result from 238328 pow (62, 3) ).


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