hello all,
i am having a variable with a value of 0000010000 and if i add the variable with some no:
suppose
i=0000010000
n=`expr $i + 1`
echo $n
the output i am reciving is 10001 .it deletes all the zeros
but i need result as 0000010001..
please help me...
thanks in... (3 Replies)
Friends,
I have a file with contents like:
interface Serial0/4/0/0/1/1/1/1:0
encapsulation mfr
multilink
group 101
Now I need to manipulate the file in such a way that to all the numbers less than 163, 63 gets added and to all numbers greater than 163, 63 gets deducted.(The numbers... (2 Replies)
Hi,
I have a file with thousands of lines like this:
Chr1 477515 . ACCCC ACCC 17.7 . INDEL;DP=17;AF1=1;CI95=0.5,1;DP4=0,1,0,3;MQ=32;PV4=1,0.036,1,1
Chr1 481987 . A AAAT 62 . INDEL;DP=11;AF1=1;CI95=0.5,1;DP4=0,0,1,3;MQ=41
I want to make a file with... (2 Replies)
I have a file like this
product qty1 qty2 value
cola 50 25 1
pepsi 100 75 2
muffin 25 30 0.5
would like to do the following operations with one line command
1) disply the line having "Qty1" greater than or equal to 50
2) display the line Qty1 - Qty2 ... (2 Replies)
I am trying to perform arithmetric, for example, to increment the value of variable $a (say 3) by 0.05 but when I tried the following expression
let a=a+0.05
or a=$((a+0.05))
both returned
3.0499999999999998
I want to keep 2 decimal places so it returns 3.05 instead. (6 Replies)
hi,
I want to do multiple arithmetic operations in a single line. I tried with the following line
total_size=`expr ($total_size + $file_size) / 1024`
this line is throwing me error.
Im working on korn shell. Can i know how to do multiple arithmetic operations in a single line (2 Replies)
Hi
I want to perform arithmetic operations on output of `wc -l`.
for example
user046@sshell ~ $ ls -l
total 0
where "total 0" will increase one line in wc -l
filecount=`ls -l | wc -l`
here $filecount will be 1 but is should be 0
how to get rid of it ? (1 Reply)
Hi All,
I would like to set decimal point to 16 in the following bash script but it has syntax error at }:
awk '{printf"%.16e", (a<500,a++,$1/(a*1.1212121212121229e-02))}' input.dat >output.datHow may I set it in the correct way please? Thank you very much! (6 Replies)
Discussion started by: sxiong
6 Replies
LEARN ABOUT PHP
eval
EVAL(3) 1 EVAL(3)eval - Evaluate a string as PHP codeSYNOPSIS
mixed eval (string $code)
DESCRIPTION
Evaluates the given $code as PHP.
Caution
The eval(3) language construct is very dangerous because it allows execution of arbitrary PHP code. Its use thus is discouraged.
If you have carefully verified that there is no other option than to use this construct, pay special attention not to pass any user
provided data into it without properly validating it beforehand.
PARAMETERS
o $code
- Valid PHP code to be evaluated. The code mustn't be wrapped in opening and closing PHP tags, i.e. 'echo "Hi!";' must be passed
instead of '<? echo "Hi!"; >'. It is still possible to leave and reenter PHP mode though using the appropriate PHP tags, e.g.
'echo "In PHP mode!"; ?>In HTML mode!<? echo "Back in PHP mode!";'. Apart from that the passed code must be valid PHP. This
includes that all statements must be properly terminated using a semicolon. 'echo "Hi!"' for example will cause a parse error,
whereas 'echo "Hi!";' will work. A return statement will immediately terminate the evaluation of the code. The code will be exe-
cuted in the scope of the code calling eval(3). Thus any variables defined or changed in the eval(3) call will remain visible
after it terminates.
RETURN VALUES eval(3) returns NULL unless return is called in the evaluated code, in which case the value passed to return is returned. If there is a
parse error in the evaluated code, eval(3) returns FALSE and execution of the following code continues normally. It is not possible to
catch a parse error in eval(3) using set_error_handler(3).
EXAMPLES
Example #1
eval(3) example - simple text merge
<?php
$string = 'cup';
$name = 'coffee';
$str = 'This is a $string with my $name in it.';
echo $str. "
";
eval("$str = "$str";");
echo $str. "
";
?>
The above example will output:
This is a $string with my $name in it.
This is a cup with my coffee in it.
NOTES
Note
Because this is a language construct and not a function, it cannot be called using variable functions.
Tip
As with anything that outputs its result directly to the browser, the output-control functions can be used to capture the output of
this function, and save it in a string (for example).
Note
In case of a fatal error in the evaluated code, the whole script exits.
SEE ALSO call_user_func(3).
PHP Documentation Group EVAL(3)