php form post values not working properly

Question

If i do the normal calculation means its working, but if i pass the value from form means its not working kindly please help me.

For example:

echo $a=(1.5 * 10E-8) - (4.6 * 10E-8);

Result : -3.1E-7 but its not working when I get the values from form.

For example:

echo $m3=($_REQUEST['m3']); echo "<br>"; \* m3 value getting from form */
echo $m2=($_REQUEST['m2']); echo "<br>"; \* m2 value getting from form */
echo $b=$m3-$m2;

Result : -3.1

I need the result fully with that scientific notation.

You will likely need to force change the variable type. It will be posted as a string by default. — scrowler, Dec 02 '13 at 06:17
This is because all values passed from a form are strings. You have to convert those strings to the correct type for your calculations to work. — vascowhite, Dec 02 '13 at 06:17
This question appears to be off-topic because it is about not having read the manual. — vascowhite, Dec 02 '13 at 06:24

score 1 · Answer 1 · answered Dec 02 '13 at 06:19

1

You need to cast the form's post values into float

echo $m3=(float)($_REQUEST['m3']); echo "<br>"; \* m3 value getting from form */
echo $m2=(float)($_REQUEST['m2']); echo "<br>"; \* m2 value getting from form */
echo $b=$m3-$m2;

answered Dec 02 '13 at 06:19

zzlalani

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V G · Answer 2 · 2013-12-02T06:23:47.713

0

Form working properly. You just need to always echo your result in scientific notation and remove * from form inputs:

$a = '1.510E-8';
$b = '4.610E-8';
echo sprintf('%e', $a-$b);
//result: -3.100000e-8

edited Dec 02 '13 at 06:23

answered Dec 02 '13 at 06:17

V G

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echo $a=(5.4 * 10E-8) - (9.8 * 10E-9); echo "
"; Result : 4.42E-7 – user3048458 Dec 02 '13 at 06:32
if i remove * from form inputs means am getting wrong output dude... – user3048458 Dec 02 '13 at 06:33
$a = '1.510E-8'; $b = '4.610E-8'; echo sprintf('%e', $a-$b); //result: 1.04x10 E -8 – user3048458 Dec 02 '13 at 06:54
V G see my last comment, like that only i need the result. – user3048458 Dec 02 '13 at 07:02
I suggest you to replace 'e' to 'x10e' in result and you will got it. – V G Dec 02 '13 at 07:04
ok V G good and nice. – user3048458 Dec 02 '13 at 12:43
`echo sprintf()` is an "antipattern". There is absolutely no reason that anyone should ever write `echo sprintf()` in any code for any reason -- it should be `printf()` without `echo` every time. – mickmackusa Apr 09 '22 at 07:40

score 0 · Answer 3 · answered Dec 02 '13 at 06:18

0

Form values return strings or arrays of strings. You need to cast them into an numeric type, if you would like to do calculations with them..

For example:

$m3 = intval($_REQUEST["m3"]);

answered Dec 02 '13 at 06:18

nl-x

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php form post values not working properly

3 Answers3