I'm new to CAS and maxima. I'd like to know whether it's feasible to do the following:
1) I have a list of parameters e.g. a, b, c
2) In PHP, I have some maxima script stored as a string, involving a, b, c, e.g.:
do {
a=random(20);
b=random(20);
c=random(20);
}while (!(a > b) || !(b > c))
Such that a, b, c are randomized to desired values and satisfy requirements.
3) Retrieve the values of a, b, c in PHP.
The purpose is to create randomized questions with reasonable parameters for students. So how can I execute the maxima script and retrieve the values of parameters? Is it suitable for my purpose?
I dont really know how your code works but if you save the maxima as a php extension it could work. Place this line of code at the start of the php file
<?php
require_once("extension/Maxima.php");
?>
For the echo example
echo $A ;
<?php
require_once($_SERVER['PM_BASE_CONFIG_PATH']);
class maxima_core {
private $executable_command;
protected $dbg_bool;
protected $dbg_info;
public function __construct($dbg=FALSE){
$this->executable_command=constant('PM_MAXIMA_EXEC_CMD');
$this->dbg_bool=$dbg;
$this->dbg_info="";
}
protected function exec($query){// to include package that is loaded by init_command
$descriptor = array(
0 => array("pipe", "r"), // stdin is a pipe that the child will read from
1 => array("pipe", "w"), // stdout is a pipe that the child will write to
2 => array("file", "/tmp/error-log.txt", "a")//constant('PM_SERVER_LOG_DIR')."/maxima/error.log", "a") // stderr is a file to write to
);
$cwd=constant('PM_ACTIVITY_PLUGIN_URL')."/engine_solver";
$MAXIMA_DIR = constant('PM_ACTIVITY_PLUGIN_DIR');
$env=array();
$init_command="display2d:false$" . "PM_ACTIVITY_PLUGIN_URL: \"" . $MAXIMA_DIR . "\"$";
//'load("/home/gabriel/github/moodledata/stack/maximalocal.mac");';
$exec_cmd=$this->executable_command." --quiet";
// --userdir='".constant('PM_ACTIVITY_PLUGIN_DIR')."/engine_solver/maxima_userdir'";
// change
$result=NULL;
$process=proc_open($exec_cmd,$descriptor,$pipes,$cwd,$env);
if(is_resource($process)){
if (!fwrite($pipes[0], $init_command)) {
echo "<br />Could not write to the CAS process!<br />
";
} else {
fwrite($pipes[0], $query);
fwrite($pipes[0], "quit();");
fclose($pipes[0]);
$result=stream_get_contents($pipes[1]);
fclose($pipes[1]);
proc_close($process);
}
}
return $result;
}
public function dbg_info(){
return $this->dbg_info;
}
}
?>
If the goal is to use Maxima to create homework problems which are presented by a web server, I think that there have been projects to do just that. I think one of them is named LON-CAPA -- a web search should find it. There might be some other projects mentioned on the related projects page at the Maxima web site. [1]
You can pass the command string in a file to Maxima, that is supported by command-line Maxima.
if your OS is Linux/Unix/MacOS:
In PHP:
exec('maxima -q -b file');
or
system('maxima -q -b file');
if your OS is Win:
$maximaDir = 'D:/Program Files/Maxima-5.30.0'; // If your maxima is installed in elsewhere, please modified this location
exec($maximaDir.'/bin/maxima.bat -q -b "result.txt"');
In Maxima, you can use stringout(); to get the result in a file, then in PHP read the file as a string, you can do any other manipulations to the string as you want.