A variable that is a math equation- how to make it DO the equation?

[kernelgpf]

I'm trying to get a number, and have this code..

 

$firetemp="100$sign[1]$random[1]";

 

Now- don't worry about the $sign or $random arrays, those are working perfectly. The problem is, the result is $firetemp equals something like "100-16" or "100+2", when I actually need the RESULT of the equation- like, right now it might give me "100+2", but I need it to give me "102". How can I do this?

 

Thanks!

[redbullmarky]

eval()

 

<?php
// slight mod to your string
$firetemp="$result = 100$sign[1]$random[1];";
eval($firetemp);

echo $result;
?>

 

[redbullmarky]

whoops my bad. forgot to escape the first $ (note it's now \$result instead of just $result):

 

<?php
// slight mod to your string
$firetemp="\$result = 100{$sign[1]}{$random[1]};";
eval($firetemp);

echo $result;
?>

 

also, it's not always essential but a good habit to get into when enclosing vars in a string to be parsed, to include them within curly braces {}. this makes sure that there's no clashes between the var name and any surrounding text.

[kernelgpf]

Okay- I tried that, I'm getting lots of errors. Here's my code-

 

$airtemp="\$result = 60{$sign[0]}{$random[0]};";
$firetemp="\$result2 = 100{$sign[1]}{$random[1]};";
$watertemp="\$result3 = 70{$sign[2]}{$random[2]};";
$icetemp="\$result4 = 30{$sign[3]}{$random[3]};";
$dvtemp="\$result5 = 70{$sign[4]}{$random[4]};";
$lighttemp="\$result6 = 80{$sign[5]}{$random[5]};";
$poisontemp="\$result7 = 90{$sign[6]}{$random[6]};";
$earthtemp="\$result8 = 70{$sign[7]}{$random[7]};";

eval($airtemp);
eval($firetemp);
eval($watertemp);
eval($icetemp);
eval($dvtemp);
eval($lighttemp);
eval($poisontemp);
eval($earthtemp);

mysql_query("update clubs set temperature='$result' where district='Air District'");
mysql_query("update clubs set temperature='$result2' where district='Fire District'");
mysql_query("update clubs set temperature='$result3' where district='Water District'");
mysql_query("update clubs set temperature='$result4' where district='Ice District'");
mysql_query("update clubs set temperature='$result5' where district='Dragon Valley District'");
mysql_query("update clubs set temperature='$result6' where district='Light District'");
mysql_query("update clubs set temperature='$result7' where district='Poison District'");
mysql_query("update clubs set temperature='$result8' where district='Earth District'");

 

And I'm getting these errors-

 

 

Parse error: syntax error, unexpected T_LNUMBER in /home/colrob/public_html/crons4246/dailies2.php(41) : eval()'d code on line 1

 

Parse error: syntax error, unexpected T_LNUMBER in /home/colrob/public_html/crons4246/dailies2.php(42) : eval()'d code on line 1

 

Parse error: syntax error, unexpected T_LNUMBER in /home/colrob/public_html/crons4246/dailies2.php(43) : eval()'d code on line 1

 

Parse error: syntax error, unexpected T_LNUMBER in /home/colrob/public_html/crons4246/dailies2.php(44) : eval()'d code on line 1

 

Parse error: syntax error, unexpected T_LNUMBER in /home/colrob/public_html/crons4246/dailies2.php(45) : eval()'d code on line 1

[redbullmarky]

can you post some example data or even the code that sets up $sign and $random ?

 

edit: this works for me:

 

// test data in arrays
$sign = array('*');
$random = array(rand(50,100));

$firetemp="\$result = 100{$sign[0]}{$random[0]};";
eval($firetemp);
echo $result;

[AndyB]

Am I missing the whole point?

 

$airtemp="\$result = 60{$sign[0]}{$random[0]};";

 

That just looks like a really ugly way to 'calculate' something. Do you actually care what $result is, or do you really want $airtemp to be the calculated result - in which case, try this:

 

$airtemp = 60 * $sign[0] * $random[0];

[kernelgpf]

<?php
include 'config.php';
$month=date('F');
if($month == 'April' || $month == 'May' || $month == 'June' || $month == 'July' || $month == 'August' || $month == 'September' || $month == 'October'){
//summer!
for($i=0;$i<7;$i++){
$random2=rand(0,30);
$random3=rand(0,1);
if($random3 == '0'){
$sign="+";
}
else{
$sign="-";
}

$random[$i]=$random2;
$sign[$i]=$sign;
}
$airtemp="\$result = 60{$sign[0]}{$random[0]};";
$firetemp="\$result2 = 100{$sign[1]}{$random[1]};";
$watertemp="\$result3 = 70{$sign[2]}{$random[2]};";
$icetemp="\$result4 = 30{$sign[3]}{$random[3]};";
$dvtemp="\$result5 = 70{$sign[4]}{$random[4]};";
$lighttemp="\$result6 = 80{$sign[5]}{$random[5]};";
$poisontemp="\$result7 = 90{$sign[6]}{$random[6]};";
$earthtemp="\$result8 = 70{$sign[7]}{$random[7]};";
}
else{
//winter!
$airtemp="\$result = 50{$sign[0]}{$random[0]};";
$firetemp="\$result2 = 80{$sign[1]}{$random[1]};";
$watertemp="\$result3 = 40{$sign[2]}{$random[2]};";
$icetemp="\$result4 = 10{$sign[3]}{$random[3]};";
$dvtemp="\$result5 = 40{$sign[4]}{$random[4]};";
$lighttemp="\$result6 = 50{$sign[5]}{$random[5]};";
$poisontemp="\$result7 = 70{$sign[6]}{$random[6]};";
$earthtemp="\$result8 = 50{$sign[7]}{$random[7]};";
}

eval($airtemp);
eval($firetemp);
eval($watertemp);
eval($icetemp);
eval($dvtemp);
eval($lighttemp);
eval($poisontemp);
eval($earthtemp);

mysql_query("update clubs set temperature='$result' where district='Air District'");
mysql_query("update clubs set temperature='$result2' where district='Fire District'");
mysql_query("update clubs set temperature='$result3' where district='Water District'");
mysql_query("update clubs set temperature='$result4' where district='Ice District'");
mysql_query("update clubs set temperature='$result5' where district='Dragon Valley District'");
mysql_query("update clubs set temperature='$result6' where district='Light District'");
mysql_query("update clubs set temperature='$result7' where district='Poison District'");
mysql_query("update clubs set temperature='$result8' where district='Earth District'");

?>

 

It's not calculating something- the $sign array is either a plus or minus sign. That's my entire script.

[sasa]

try

<?php
include 'config.php';
$month=date('F');
$month_arr = array('April', 'May', 'June', 'July', 'August');
$district_arr = array(
'Air District' => 60, 
'Fire District' => 100, 
'Water District' => 70, 
'Ice District' => 30, 
'Dragon Valley District' => 70, 
'Light District' => 80, 
'Poison District' => 90, 
'Earth District' => 70
);
if(in_array($month, $month_arr)){
//summer!
foreach ($district_arr as $district => $value){
	$random = rand(0, 30) * (rand(0,1) * 2 - 1);
	// or use  just $random = rand(-30, 30);
	$result = $value + $random;
	print("update clubs set temperature='$result' where district='$district'"); // change print to mysql_query()
}
}
?>

sorry i update code

[Orio]

As Andy suggested:

 

<?php

include 'config.php';

$month=date('F');
if($month == 'April' || $month == 'May' || $month == 'June' || $month == 'July' || $month == 'August' || $month == 'September' || $month == 'October')
{
//summer!
for($i=0;$i<7;$i++)
{
	$random2 = rand(0,30);
	$random3 = rand(0,1);
	if($random3 == '0')
		$sign = 1;
	else
		$sign = -1;

	$random[$i] = $random2;
	$sign[$i] = $sign;
}
$result = 60 * $sign[0] + $random[0];
}

mysql_query("update clubs set temperature='$result' where district='Air District'");

?>

 

 

Orio.