multiplication math not working ?

**Rik** · Feb 7 '07, 04:15 PM

Re: multiplication math not working ?

One <david.hunter@g mail.comwrote:

hi group -
>
I had this in a function - so I've just moved this out of the function
for readabilty.
>
Can someone please tell me WHY does this not return the result of :
n1 times n2
>
As I said - I took it out of the function just for readability :
In my php file :
>
$number_percent ="25";
echo "history['order_total'] is ".$history['order_total']." ";
echo "number_per cent is ".$number_perce nt." ";
$total=(($histo ry['order_total'])*$number_perce nt);
echo "total is ".$total." ";
>
And here is the output in the browser :
history['order_total'] is $241.47
number_percent is 25
total is 0
>
WHY ? Any advice or pointers would be much appreciated!

Because '$241.47' is not a number, it's a string representation of a
currency. PHP doesn't know anything about that, 'currency' is not a type..
When performing math on it, PHP will try to make a number out of it, and
encounters '$' as the first character. This is not something it
recognizes, and it will default to 0. And 0 * 25 = 0.

You might want to remove the currency symbol from the string, and just add
it back when you have to echo/print the total.

Also, I'd think if $number_percent = 25, you might want $total =
$history['order_total'] * (1+($number_per cent/100));
--
Rik Wasmus

**Jerry Stuckle** · Feb 7 '07, 04:45 PM

Re: multiplication math not working ?

One wrote:

hi group -
>
I had this in a function - so I've just moved this out of the function
for readabilty.
>
Can someone please tell me WHY does this not return the result of :
n1 times n2
>
As I said - I took it out of the function just for readability :
In my php file :
>
$number_percent ="25";
echo "history['order_total'] is ".$history['order_total']." ";
echo "number_per cent is ".$number_perce nt." ";
$total=(($histo ry['order_total'])*$number_perce nt);
echo "total is ".$total." ";
>
And here is the output in the browser :
history['order_total'] is $241.47
number_percent is 25
total is 0
>
WHY ? Any advice or pointers would be much appreciated!
>

$number_percent is a string containing 25, not the numeric value 25.
When you use a string in a calculation it's numeric value is zero.

Try
$number_percent =25;

instead (and ensure that $history['order_total'] is also numeric).

--
=============== ===
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attgl obal.net
=============== ===

**One** · Feb 7 '07, 04:55 PM

Re: multiplication math not working ?

Because '$241.47' is not a number, it's a string representation of a

currency. PHP doesn't know anything about that, 'currency' is not a type.
When performing math on it, PHP will try to make a number out of it, and
encounters '$' as the first character. This is not something it
recognizes, and it will default to 0. And 0 * 25 = 0.
>
You might want to remove the currency symbol from the string, and just add
it back when you have to echo/print the total.
>
Also, I'd think if $number_percent = 25, you might want $total =
$history['order_total'] * (1+($number_per cent/100));

Hi Rik - thank you the reply.

I used string replace to remove the dollar sign, then I simply
multiplied the two numbers, and it is still calculating as zero.
Can I cast this variable to an int ??

Input :
$number_percent ="25";
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo "strip the $ sign ".$removeit."";
$total = ($removeit * (1+($number_per cent/100)));
echo " total is ".$total." ";

Output :
history['order_total'] is $241.47
strip the $ sign 241.47
total is 0

:-(

**One** · Feb 7 '07, 04:55 PM

Re: multiplication math not working ?

On Feb 7, 11:34 am, Jerry Stuckle <jstuck...@attg lobal.netwrote:

$number_percent is a string containing 25, not the numeric value 25.
When you use a string in a calculation it's numeric value is zero.
>
Try
$number_percent =25;
>
instead (and ensure that $history['order_total'] is also numeric).

Hi Jerry - thanks much for trying.
Same result :
Input :
$number_percent =25;
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo "strip the $ sign ".$removeit."";
$total = ($removeit * $number_percent );
echo " total is ".$total." ";

Output :
history['order_total'] is $241.47
strip the $ sign 241.47
total is 0

This is bonkers - I'm *sure* I have done this type of thing in the
past without issue. :-(

**Rik** · Feb 7 '07, 05:45 PM

Re: multiplication math not working ?

One <david.hunter@g mail.comwrote:

On Feb 7, 11:34 am, Jerry Stuckle <jstuck...@attg lobal.netwrote:

>$number_percen t is a string containing 25, not the numeric value 25.
>When you use a string in a calculation it's numeric value is zero.
>>
>Try
> $number_percent =25;
>>
>instead (and ensure that $history['order_total'] is also numeric).

>
Hi Jerry - thanks much for trying.
Same result :
Input :
$number_percent =25;
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo "strip the $ sign ".$removeit."";
$total = ($removeit * $number_percent );
echo " total is ".$total." ";
>
Output :
history['order_total'] is $241.47
strip the $ sign 241.47
total is 0
>
This is bonkers - I'm *sure* I have done this type of thing in the
past without issue. :-(

This works here:
<?php
$history['order_total'] = '$241.47';
$number_percent ="25";//should be without the quotes indeed, but just to
show PHP can cast this correctly
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo "strip the $ sign ".$removeit."";
$total = ($removeit * (1+($number_per cent/100)));
echo " total is ".$total." ";
?>

So I'd say there's something wrong with the exact contents of
$history['order_total'] in your script.

What if you do this (a bit overkill):

$removeit = preg_replace('/[^0-9.]/','',$history['order_total']);

If this doesn't work, I'm very curious what the output of
floatval($histo ry['order_total'])(or floatval($remov eit)) is....
--
Rik Wasmus

**Jerry Stuckle** · Feb 7 '07, 06:15 PM

Re: multiplication math not working ?

One wrote:

On Feb 7, 11:34 am, Jerry Stuckle <jstuck...@attg lobal.netwrote:

>$number_percen t is a string containing 25, not the numeric value 25.
>When you use a string in a calculation it's numeric value is zero.
>>
>Try
> $number_percent =25;
>>
>instead (and ensure that $history['order_total'] is also numeric).

>
Hi Jerry - thanks much for trying.
Same result :
Input :
$number_percent =25;
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo "strip the $ sign ".$removeit."";
$total = ($removeit * $number_percent );
echo " total is ".$total." ";
>
Output :
history['order_total'] is $241.47
strip the $ sign 241.47
total is 0
>
This is bonkers - I'm *sure* I have done this type of thing in the
past without issue. :-(
>
>

Rik caught one and I caught the other (I missed the dollar sign).

Both are string in your setup. Use floatval() to convert your
$history['order_total'] to a floating point number.

--
=============== ===
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attgl obal.net
=============== ===

**Jerry Stuckle** · Feb 7 '07, 06:15 PM

Re: multiplication math not working ?

One wrote:

On Feb 7, 11:34 am, Jerry Stuckle <jstuck...@attg lobal.netwrote:

>$number_percen t is a string containing 25, not the numeric value 25.
>When you use a string in a calculation it's numeric value is zero.
>>
>Try
> $number_percent =25;
>>
>instead (and ensure that $history['order_total'] is also numeric).

>
Hi Jerry - thanks much for trying.
Same result :
Input :
$number_percent =25;
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo "strip the $ sign ".$removeit."";
$total = ($removeit * $number_percent );
echo " total is ".$total." ";
>
Output :
history['order_total'] is $241.47
strip the $ sign 241.47
total is 0
>
This is bonkers - I'm *sure* I have done this type of thing in the
past without issue. :-(
>
>

Better yet - store the data as a floating point value without the dollar
sign. Then insert the dollar sign when you're ready to print.

--
=============== ===
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attgl obal.net
=============== ===

**Rik** · Feb 7 '07, 06:25 PM

Re: multiplication math not working ?

Jerry Stuckle <jstucklex@attg lobal.netwrote:

Better yet - store the data as a floating point value without the dollar
sign. Then insert the dollar sign when you're ready to print.

Indeed, check money_format().
--
Rik Wasmus

**One** · Feb 8 '07, 06:35 PM

Re: multiplication math not working ?

On Feb 7, 1:00 pm, Jerry Stuckle <jstuck...@attg lobal.netwrote:

One wrote:

On Feb 7, 11:34 am, Jerry Stuckle <jstuck...@attg lobal.netwrote:

$number_percent is a string containing 25, not the numeric value 25.
When you use a string in a calculation it's numeric value is zero.

>

Try
$number_percent =25;

>

instead (and ensure that $history['order_total'] is also numeric).

>

Hi Jerry - thanks much for trying.
Same result :
Input :
$number_percent =25;
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo "strip the $ sign ".$removeit."";
$total = ($removeit * $number_percent );
echo " total is ".$total." ";

>

Output :
history['order_total'] is $241.47
strip the $ sign 241.47
total is 0

>

This is bonkers - I'm *sure* I have done this type of thing in the
past without issue. :-(

>
Rik caught one and I caught the other (I missed the dollar sign).
>
Both are string in your setup. Use floatval() to convert your
$history['order_total'] to a floating point number.

Hi guys - thanks SO much for your replies - it is still not working -
I'm using the floatval properly but it is returning a zero :

Input :
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo $removeit;
$floatandremove = floatval($remov eit);
echo " floatandremo ve is ".$floatandremo ve;
exit;

Output :
history['order_total'] is $241.47
241.47
floatandremove is 0

This is getting crazy!

**Rik** · Feb 8 '07, 07:05 PM

Re: multiplication math not working ?

One <david.hunter@g mail.comwrote:

Input :
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo $removeit;
$floatandremove = floatval($remov eit);
echo " floatandremo ve is ".$floatandremo ve;
exit;
>
Output :
history['order_total'] is $241.47
241.47
floatandremove is 0
>

There must be something else going on with your currency string.
Please use this on that string, and report it's results back to us:

echo preg_replace('/(.)/se','"[".ord("$1") ."]"',$history['order_total']);
--
Rik Wasmus

**One** · Feb 8 '07, 07:55 PM

Re: multiplication math not working ?

On Feb 8, 2:01 pm, Rik <luiheidsgoe... @hotmail.comwro te:

One <david.hun...@g mail.comwrote:

Input :
echo "history['order_total'] is ".$history['order_total']." ";
$removeit=str_r eplace('$' ,'', $history['order_total']);
echo $removeit;
$floatandremove = floatval($remov eit);
echo " floatandremo ve is ".$floatandremo ve;
exit;

>

Output :
history['order_total'] is $241.47
241.47
floatandremove is 0

>
There must be something else going on with your currency string.
Please use this on that string, and report it's results back to us:
>
echo preg_replace('/(.)/se','"[".ord("$1") ."]"',$history['order_total']);
--
Rik Wasmus

Thanks again Rik - here you go :

Input :
echo "history['order_total'] is ".$history['order_total']." ";
echo preg_replace('/(.)/se','"[".ord("$1") ."]"',
$history['order_total']);
exit;

Output :
history['order_total'] is $241.47
[60][98][62][36][50][52][49][46][52][55][60][47][98][62]

**Toby A Inkster** · Feb 9 '07, 11:05 AM

Re: multiplication math not working ?

One wrote:

history['order_total'] is $241.47
[60][98][62][36][50][52][49][46][52][55][60][47][98][62]

$history['order_total'] contains '$241.47'. This is not a number.

$history['order_total'] = (float)preg_rep lace('/[^0-9\.]/', '',
strip_tags($his tory['order_total']));

--
Toby A Inkster BSc (Hons) ARCS
Contact Me ~ http://tobyinkster.co.uk/contact
Geek of ~ HTML/CSS/Javascript/SQL/Perl/PHP/Python*/Apache/Linux

* = I'm getting there!

**One** · Feb 12 '07, 04:25 PM

Re: multiplication math not working ?

On Feb 9, 5:51 am, Toby A Inkster <usenet200...@t obyinkster.co.u k>
wrote:

One wrote:

history['order_total'] is $241.47
[60][98][62][36][50][52][49][46][52][55][60][47][98][62]

>
$history['order_total'] contains '$241.47'. This is not a number.
>
$history['order_total'] = (float)preg_rep lace('/[^0-9\.]/', '',
strip_tags($his tory['order_total']));

Mr. Toby!
You da man - thanks very much!

Thank you also to Rik and Jerry for taking the time to resolve this
issue.

multiplication math not working ?

multiplication math not working ?

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