Execute multiple sage commands from php script

Question

I have installed Sage math on my ubuntu server. I can run sage commands by ssh terminal such as

$sage:   
$sage:  f = x^2
$sage:  f.diff(x)

I would like to do on a php script

exec('sage');
exec('sage: f = 5x^3');
$fprime = exec('sage: latex(f.diff(x))');

echo $fprime; 

I would expect "15x^2" as output but that's not happening .. however on ssh terminal all is good..
all help would be greatly appreciated..

Answer 1

I'm not completely sure of what you want to achieve. PHP's exec function executes a shell command, and that's all. Read http://fr2.php.net/manual/en/function.exec.php.

sage: f = 5*x^3 is not a shell command. You can run sage scripts directly via the command line using the -c switch :

./sage -c 'print latex((5*x^3).diff())'

will print 15 \, x^{2} to the terminal. In PHP you can grab this output by passing a second argument to exec:

exec("./sage -c 'print latex((5*x^3).diff())'", $output);
echo $output[0];