elseif statement is not working? - php

Question

I write a logic to round value based on fraction part value. When i execute this code, elseif block is not executed. Here is my code
<?php
function roundRating($rating)
{
if($rating>=5 && $rating<0){
$rating=0;
}
$a=(int)$rating/1;
$b= $rating-$a;
if(($b>=.1) && ($b<=.2)){
$b=0;
$rating=$a;
}
elseif(($b>=.3 && $b<=.4)|| ($b>=.6 && $b<=.7)){
$b=.5;
$rating=$a+$b;
}
elseif(($b>=.8) && ($b<=.9)){
$b=1;
$rating=$a+$b;
$a=$rating;
}
else{}
return $rating;
}
echo roundRating(3.3);
?>
for this value 3.3, the output should be 3.5. But currently it will return passed value 3.3 instead of 3.5. Kindly help me to find out the problem in the above code. Thanks in advance.

Answer 1

I've done my own version of the function which might be cleaner, and i think generates the output required:
function roundRating($rating) {
if( $rating > 5) {
return 5; // Note: assuming the >5 case of 0 was a bug and it was meant to cap it to 5
} elseif( $rating < 0 ) {
return 0;
}
$number = floor($rating);
$remainder = $rating * 10 % 10;
if( $remainder <= 2 ) {
return $number;
} elseif( $remainder >= 8 ) {
return $number + 1;
} else {
return $number + 0.5;
}
}
echo roundRating(3.4); // 3.5
echo roundRating( 3.0) ; // 3
echo roundRating( 6) ; // 5
echo roundRating( 3.8) ; // 4

Answer 2

Please follow the following code given bellow.we some times face problem in floating value comparison. So, it is useful to specify how much number we will consider after decimal point. In the following code value of b is specified that it takes only 3 numbers after decimal point.
For details please visit:
is-floating-point-math-broken
To check online please visit:
Online check
function roundRating($rating)
{
if($rating>=5 && $rating<0){
$rating=0;
}
$a=(int)$rating/1;
$b= sprintf('%3f',$rating-$a);
if(($b>=.1) && ($b<=.2)){
$b=0;
$rating=$a;
}
elseif(($b>=.3 && $b<=.4)|| ($b>=.6 && $b<=.7)){
$b=.5;
$rating=$a+$b;
}
elseif(($b>=.8) && ($b<=.9)){
$b=1;
$rating=$a+$b;
$a=$rating;
}
else{}
return $rating;
}
echo roundRating(3.3); // 3.5
?>

Answer 3

Replace your code with below code.
<?php
function roundRating($rating)
{
if($rating >= 5 && $rating < 0){
$rating=0;
}
else
{
$a=(int)$rating/1;
$b= $rating-$a;
echo $a ."</br>";
echo $b."</br>";
if(($b >= 0.1) && ($b <= 0.2)){
$b=0;
$rating=$a;
}
elseif(($b >=0.3 || $b<=0.4) && ($b>=0.6 || $b<=0.7)){
$b=.5;
$rating=$a+$b;
}
elseif(($b>=.8) || ($b<=.9)){
$b=1;
$rating=$a+$b;
$a=$rating;
}
else{}
}
return $rating;
}
echo roundRating(3.3);
?>
Here i have did two change first add else condition your rating calculation work if $rating is not greater than 5 or less than 0. and second in one of your else if condition is change which is given below.
elseif(($b >=0.3 || $b<=0.4) && ($b>=0.6 || $b<=0.7)){
//echo "here";
$b=.5;
$rating=$a+$b;
}
i hope it will helps you.

Answer 4

Floating point numbers have hidden/limited precision in C - so you can't trust them to the last digit. There's more of a writeup on this at http://php.net/manual/en/language.types.float.php
If you were to round it to 1 decimal place, you'll get 3.5:
$b= round($rating-$a, 1);

Answer 5

To start with :
if($rating>=5 && $rating<0)
will always be false . A variable can't be greater than 5 and less than 0 at the same time.
Regarding
elseif(($b>=.3 && $b<=.4)|| ($b>=.6 && $b<=.7)){
$b=.5;
$rating=$a+$b;
}
what practical differece would it make with :
elseif(($b>=.3 && $b<=.7)){
$b=.5;
$rating=$a+$b;
}
unless you write :
else{
$rating+=some_value;// forthe inifinite number of values between .4 & .6?
}
Regarding,
elseif(($b>=.8) && ($b<=.9)){
$b=1;
$rating=$a+$b;
$a=$rating; // This statement is redundant
}
Since you return $rating from the function, $a=$rating; is redundant.
Having said the above things, I feel below would be a much simpler implementation, with results almost identical to desired one :
<?php
function round_rating($rating){
if($rating<0 || $rating>5){
$rating=0;
return $rating;
}
$t_rating=(int)$rating; //$t_rating short for trimmed_rating :)
$dif=$rating-$t_rating; //$dif is the short for difference :)
if($dif <= .2){
return($t_rating);
}
elseif($dif <= .7){
return((float)$t_rating+.5);
}
else{
return((float)$t_rating+1);
}
} // round_rating function ends here :)
/*Test time*/
printf("Round rating for %0.2f : %0.2f\n",6,round_rating(6));
printf("Round rating for %0.2f : %0.2f\n",0.2,round_rating(0.2));
printf("Round rating for %0.2f : %0.2f\n",1.4,round_rating(1.4));
printf("Round rating for %0.2f : %0.2f\n",2.8,round_rating(2.8));
printf("Round rating for %0.2f : %0.2f\n",4.6,round_rating(4.6));
printf("Round rating for %0.2f : %0.2f\n",-1,round_rating(-1));
?>
Output :
Round rating for 6.00 : 0.00
Round rating for 0.20 : 0.00
Round rating for 1.40 : 1.50
Round rating for 2.80 : 3.00
Round rating for 4.60 : 4.50
Round rating for -1.00 : 0.00

Answer 6

Thank you all for your answers. Finally i got the answer. Here is my answer.
function roundRating($rating)
{
if($rating>5 ){
$rating=0;
return $rating;
}
elseif($rating<=0)
{
$x=0;
return $rating;
}
$a=(int)$rating/1;
$b= $rating-$a;
$b= (int)round(($b*10),0);
if($b<=2)
{
$rating=$a;
return $rating;
}
elseif($b>=3 && $b<=7){
$rating=$a+.5;
return $rating;
}
elseif($b>=8){
$rating=$a+1;
return $rating;
}
else{}
}
echo roundRating(3.2); //3
echo roundRating(3.3); //3.5
echo roundRating(3.7); //3.5
echo roundRating(3.8); //4