Maybe the question is simple, but I can't find the answer.
What I need to do is to round number to 2 places after comma.
Im using this:
round(($data/$count*100), 2)
And when I get number like:
60.36036036036012 and : 37.83783783783808 is OK, because it's: 60.36 and 37.84
But why this:
1.8018018018018036
Is rounded to this:
1.8000000000000003
How to round always to 2 places, after comma?
You should get 1.8 unless you use something like old PHP version with some sort of related bugs. Still, if you want to see 1.80 you need to format output string, otherwise trailing zero will be stripped by default. The most flexible approach would be to use sprintf() formatting, like this:
$val = 1.8000000000000003;
printf("%.02f", round( $val, 2 ));
which would produce
1.80
The key is "%.02f" which means you want to format (f)loating point value, with two digits after dot, padded with 0 when needed (like this case).
See the sprintf() docs for more about available formatting possibilites.
Use PHP NumberFormatter class http://es.php.net/manual/es/class.numberformatter.php
Related
I want to show a float number in php string.
something like:
My float number is: 0.00003485
But when I am using echo I see it like this:
My float number is: 3.485E-5
Also, I know I can use printf("%.10f",$float) code, but I need to use it in lots of places in my string, So I can't use printf.
What code should I use on a string, to show floats as they are? I don't want that shorted number (3.485E-5).
At some condition i am prefer declaration float number as string:
MyFloatNumber = "0.0000000000000000000000003485";
so,
echo MyFlatNumber;
//0.0000000000000000000000003485
I know I can use printf("%.10f",$float) code, but I need to use it in lots of places in my string, So I can't use printf.
I have to respectfully disagree with that:
printf('My float number is: %1$.8f (again: %1$.8f; once more: %1$.8f)', 0.00003485);
Or, if you need it in a string:
$foo = sprintf('My float number is: %1$.8f (again: %1$.8f; once more: %1$.8f)', 0.00003485);
Of course, if you mean it's against project style guidelines or company policy, that's another story.
What code should I use on a string, to show floats as they are?
Really? Floats in PHP are a 64-bit IEEE 754 double precision format bitmap. According to this online converter, number 0.00003485 would be:
0010010001010111110011100001110100101110111001001111
Of course, they aren't actual ones and zeroes but different voltage levels ;-)
You can write a function to handle this in any way you want. Why not?
function fval($f, $precision = 9) {
return number_format($f, $precision);
}
Then any place you need to format, call it out:
$f = 3.485E-5;
echo fval($f); // this will print: 0.000003485
I am trying to make this calculation in php but is giving me wrong result. I think that is right.
And if i do 5000.00 - 100.10 it works, but i want the 5,000.00 to work too.
This is my code:
To create the 5,000.00 i have used number_format(5000, 2).
Aswell to the 100.10
$total = $value1 - $value2;
echo $total;
?>
$total = -95.00
I am trying to make this calculation in php but is giving me wrong result. I think that is right.
And if i do 5000.00 - 100.10 it works, but i want the 5,000.00 to work too.
Please Help...
If you want to do arithmetic on number, you can't have the thousands separator (,). What's happening is 5,000.00 is being read as 5 (it stops interpreting it as a number as soon as it hits the comma) and then you're getting 5 - 100.10 which is -95.10 (I'm thinking you left off the .10 in your example.
You'll need to convert first:
$value1 = floatval(str_replace(',', '', $original_value1))
$value2 = floatval(str_replace(',', '', $original_value2))
I'm assuming here that you have them as strings originally. These remove the comma separator.
It sounds like you're confusing rendering in the UI with calculations.
It's perfectly reasonable for a user to see currencies rendered according to their locale rules (e.g. a String "$1,000.00" in USA), but the calculations in the back need to done on a floating point number (e.g. 1000.0).
So you have to be able to convert back and forth between them. You can't make arithmetic operations work on a String. Better to parse the String to a float, do the operations, then convert that back to String for rendering.
I have the following line of code in javascript:
(Math.random() + "") * 1000000000000000000
which generates numbers like:
350303159372528000
I tried the same thing in PHP with this:
rand()*1000000000000000000
Which returns:
2.272e+21
I need to use PHP as the number generated will be stored as a SESSION variable and will be used by JavaScript later on.
How do I get PHP to force the number to be an int rather than a float?
EDIT PHP seems to struggle with this.
Would it work if I just generated the rand number in PHP saved it to the SESSION and then done the multiplying by 1000000000000000000 in JavaScript?
How would I go about this?
I'd recommend calling
PHP_INT_MAX
To see if your PHP installation can handle an integar that large. I'm guessing it can't which is why it is knocking it down to scientific notation.
I'd suggest converting your result to an int:
intval(rand()*1000000000000000000)
That said, see Kolink and Jeremy1026 answers for precision issues. If you only need an unique identifier, see Truth's answer.
Update: if you're using strings to represent your numbers, don't want or can't use an arbitrary precision library, and don't stricly need perfecly fair random numbers, you could generate smaller numbers and concat them together:
strval(rand()*999999999 + 1) . strval(rand()*1000000000)
(The +1 is to avoid a leading zero in your result; note also that your number will never have a single digit, but every other number is possible)
For a random number with (exactly) 18 digits, you can also use str_pad in the 2nd part, to fill it with leading zeros:
strval(rand(100000000,999999999)) .
str_pad(strval(rand(0,999999999)), 9, "0", STR_PAD_LEFT)
If you need a unique identifier (which is what it looks like you're trying to do), please use PHP's uniqid() function.
floor() / ceil() / round() / (int) / intval() will convert the number to int.
Also, rand() takes two arguments. If ints are supplied - it will return an integer
And printf() should take care of printing in the format you wish (printf('%d', $int) should do the trick)
In the end I solved the issue like this:
<?php
error_reporting(0);
function RandNumber($e){
for($i=0;$i<$e;$i++){
$rand = $rand . rand(0, 9);
}
return $rand;
}
echo RandNumber(18);
// Outputs a 18 digit random number
?>
When i make the following multiplication in PHP:
$ret = 1.0 * 0.000000001;
i get the result: 1.0E-9
I want to convert this result into the normal decimal notation, how can i do this?
sprintf('%f',$ret) doesn't work, it returns 0.000000. Overflow?
sprintf('%f',$ret) doesn't work, it returns 0.000000. Overflow?
sprintf works, however you miss some point here.
0.000000 is not overflow. It's just that sprintf for the %f modifier uses 6 digits per default. Also please take care that %f is locale aware, %F is probably better suited.
You might want to use more digits, e.g. let's say 4 000 000 (four million):
$ php -r "printf('%.4000000F', 1*0.000000001);"
Notice: printf(): Requested precision of 4000000 digits was truncated to PHP maximum of 53 digits in Command line code on line 1
Call Stack:
0.0001 319080 1. {main}() Command line code:0
0.0001 319200 2. printf() Command line code:1
0.00000000100000000000000006228159145777985641889706869
As this example shows, there is not only a common value (6 digits) but also a maximum (probably depended on the computer system PHP executes on), here truncated to 53 digits in my case as the warning shows.
Because of your question I'd say you want to display:
0.000000001
Which are nine digits, so you need to write it that way:
sprintf('%.9F',$ret)
However, you might want to do this:
rtrim(sprintf('%.20F', $ret), '0');
which will remove zeroes from the right afterwards:
0.000000001
Hope this is helpful.
You need to add precision specifier (how many decimal digits should be displayed for floating-point numbers). Something like this:
echo sprintf('%.10f',$ret); // 0.0000000010
If you have no idea what number you should specify, just give it a big number and combine it with rtrim().
echo rtrim(sprintf('%.20f', $ret), '0'); // 0.000000001
The code above will strip any 0's from the end of the string.
I suggest the use BCMath for more accuracy when you are calculating with decimal numbers. That makes sure that you actually get the results you want.
To print what you want, you should specify the precision and use %.9f, since it defaults to displaying 6 decimal numbers. That makes it something like this (just like bsdnoobz already said):
sprintf('%.9f',$ret);
To align to your system's settings and limitations, you could use serialize_precision to get the most accurate result possible.
echo rtrim(sprintf('%.'.ini_get('serialize_precision').'f', $ret));
I do not recommend using the non-locale aware %F since your question only makes sense for display purposes. Respecting locale makes for a better UX.
I have a loop that calculates a couple revenue values then adds them together, like this:
$SalesGrowth = $C2012Sales+$C2011Sales;
In some cases, this works, and I get the expected, e.g.: 761.9 + 759.0 = 1520.9
In others, it looks like PHP randomly decides to round incorrectly (??) AND change the units (??) and I get:
8,788.0 + 8,794.3 = 16
What is going on here? I've even tried echoing out the separate sales values separated by a space, and they show up correctly, so the underlying figures aren't wrong.
Interpreted as a number, 8,788.0 is just 8, and parsing stops at the comma.
You'll need some locale-aware number parsing if you want to allow gimmicks like thousands-separators.
Update: If you have the Zend Framework, you can do this:
require_once('Zend/Locale/Format.php');
$locale = new Zend_Locale('en_GB'); // #1
$v = "8,410.5";
$n = Zend_Locale_Format::getNumber($v, array('locale' => $locale,'precision' => 3));
echo 2 * $number; // prints "16821"
Instead of hard-coding the locale, you could try and take it from the environment: new Zend_Locale(setlocale(LC_ALL, ""))
Dude the comma issue....
remove all the commas from the numbers before adding them...
str_replace(",","",$no1);
This is pretty simple... When you ask PHP to use the + operator, it will implicitly convert these strings such as "8,788.0" to an numeric value. Since you have a , character, it terminates the usefulness of the number, and it results in it being interpreted as 8. And so on...
Get rid of the non [0-9.] characters and it will work better.
Notice that 761.9 is a valid number, while 8,788.0 is not (from PHP's point of view).
So 8,788.0 in number context will evaluate as 8, just like 8,794.3. And 8+8 = 16.
To fix this problem, process your data to make numbers formatted properly.