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Function to calculate percentage

Discussion in 'PHP' started by pradeep, Feb 21, 2007.

  1. pradeep

    pradeep Team Leader

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    I had to write the code to get percentage every time I needed it, so I thought it'd be much better to have a function for the purpose, here's the function I wrote.

    PHP:
    function percentage($int1$int2
     {
         
    $per $int1 $int2;
         
    $res $per 100;
         return 
    $res;
     }
     
  2. shabbir

    shabbir Administrator Staff Member

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    This is not a good way of doing it as you may not get correct results. I am not sure about it in PHP but let me know what is the output for the forllowing.
    $int1 = 48
    $int2 = 100
     
  3. pradeep

    pradeep Team Leader

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    Will return 48!
     
  4. shabbir

    shabbir Administrator Staff Member

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    But it should not as 48/100 in integer should be 0
     
  5. pradeep

    pradeep Team Leader

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    the arguments passed are integers, but $res is casted to int.
     
  6. shabbir

    shabbir Administrator Staff Member

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    What is the type for $per
     
  7. pradeep

    pradeep Team Leader

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    By default there is not data type specified to a variable, it takes the data type of the value assigned. e.g. $a = 10/6; here $a becomes float, and $a = 10/2 here $a becomes int and $a = 'Shabbir' here $a becomes string.
    So in this case $per = $int1 / $int2; $per becomes float.
     
  8. DaWei

    DaWei New Member

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    I would suggest that the parameters shouldn't be ints, anyway. Someone might want to know the percentage of a fractional number. Someone also might think that the return type has been coerced to match an the input arguments (integers), rather than having been set by PHPs "autotyping".

    I would also suggest that the relationship, a/b*100, is far too simple to waste the overhead of a function call. On the other hand, I come from the days when resources weren't so abundant that one could be profligate with them.
     

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