/media/sda-magnetic/david/Dokumente-14/linux/mypython/funktionsplotter22.php

<?php
$flg = false;

/*$myplotexpr = "plot(exp(x));
do
    plot(sin(k*x));
    \$k=k+1;
    do
        plot(exp(i*k*x));
        \$i=i+1
    while \$i<9
while \$k<4";
*/

$myplotexpr = file_get_contents ("./compiler.txt");

if (strstr ($myplotexpr, "PLOT:")) {
    $myplotexpr = str_replace ("PLOT:", "", $myplotexpr);
    $flg = true;
}
else
    exit (1);
    
$myplotexpr = preg_replace("/\s+/", "",  $myplotexpr); 
$myplotexpr = str_replace ("&lt;", "<", $myplotexpr);
$myplotexpr = str_replace ("&gt;", ">", $myplotexpr);
$upper = 4.0;
$lower = -4.0;
$i = 0;
$k = 0;
$stckptr = 0;
$while_count = 0;

for ($ch = 'a';  $ch <= 'z';  $ch++)
    $a [$ch] = 0;
    
plot_start ();
sequnce ();
plot_ends ();

echo $a['k'];

function push ($val) {
    global $stck;
    global $stckptr;
    global $myplotexpr;
    
    if ($stckptr > 32)
        exit ("error !!!!!!!!!");
    $stck [$stckptr] = $val;
    $stckptr ++;
}

function pop () {
    global $stck;
    global $stckptr;
    $stckptr--;
    if ($stckptr < 0)
        exit ("bug!!!!!");
    return $stck [$stckptr];
}

function plot_start () {
    global $upper;
    global $lower;
    global $myImage;
    global $myBlue;
    global $myRed;
    global $myplotexpr;
    
    $myImage = imagecreatetruecolor(800, 600);
    $trans_colour = imagecolorallocatealpha($myImage, 127, 127, 255, 0);
    imagefill($myImage, 0, 0, $trans_colour);
    $myBlue = imagecolorallocate($myImage, 10, 20, 200);
    $myRed = imagecolorallocate($myImage, 200, 10, 10);


    imageline ($myImage, 0-$lower*(800/($upper-$lower))-1, 0, 0-$lower*(800/($upper-$lower))-1, 600, $myRed);;
    imageline ($myImage, 0-$lower*(800/($upper-$lower)), 0, 0-$lower*(800/($upper-$lower)), 600, $myRed);;
    imageline ($myImage, 0-$lower*(800/($upper-$lower))+1, 0, 0-$lower*(800/($upper-$lower))+1, 600, $myRed);;


    imageline ($myImage, 0, 300, 800, 300, $myRed);;
    imageline ($myImage, 0, 301, 800, 301, $myRed);;
    imageline ($myImage, 0, 299, 800, 299, $myRed);;
}

function plot_ends () {
    global $myplotexpr;
    global $myImage;
    global $outstr;
    ob_start();
    imagepng($myImage, "./func000.png");
    base64_encode(ob_get_clean());
    sleep (1);
    unset($outstr);  
    echo "<div id=\"idfuncplotdiv\">";
    echo "<img width=\"98%\" id=\"idfuncplot\" src=\"./func000.png\">";
    echo "</div>";
    echo "<script src=\"./scripts/funcplot.js\"></script>";
}

function plot () {
    global $k;
    global $i;
    global $j;
    global $upper;
    global $lower;
    global $myImage;
    global $myRed;
    global $myBlue;
    global $a;
    global $myplotexpr;
    
    $i = $k;
    
    
    if (!(($myplotexpr [$i] == 'p') &&
    ($myplotexpr [$i+1] == 'l') &&
    ($myplotexpr [$i+2] == 'o') &&
    ($myplotexpr [$i+3] == 't') &&
    ($myplotexpr [$i+4] == '(')))
        return false;
    
    $i += 5;
    $k += 5;

    $a ['x'] =  $lower;
    $max = expr ();
    for ($a ['x'] = $lower+(($upper-$lower)/800);  $a ['x'] < $upper;  $a ['x'] += (($upper-$lower)/800)) {
        $i = $k;
        if(($t = expr ()) > $max)
            $max = $t;
    }


    $i = $k;
    $a ['x'] = $lower;
    $oldt = expr ();
    $oldt = $oldt / $max;
    $oldt = $t * 300 + 300;
    $oldti = ceil ($oldt);
    for ($a ['x'] = $lower+(($upper-$lower)/800), $j = 0;  $a ['x'] < $upper;  $a ['x'] += (($upper-$lower)/800), $j++) {
        $i = $k;
        $t = expr ();
        $t = $t / $max;
        $t = $t * 300 + 300;
        $ti = ceil ($t);
        imageline ($myImage, $j, 600-$oldti, $j+1, 600-$ti, $myBlue);;
        imageline ($myImage, $j, 600-$oldti-1, $j+1, 600-$ti-1, $myBlue);;
        imageline ($myImage, $j, 600-$oldti-2, $j+1, 600-$ti-2, $myBlue);;
        $oldt = $t;
        $oldti = ceil ($oldt);
    }
    
    
    if (($myplotexpr [$i] != ')')) {
        exit ( "error!!!!");
        return false;
    }
    $i++;
    $k = $i;
    return true;
}

function sequnce () {
    global $myplotexpr;
    global $k;
    statement ();
    if ($myplotexpr [$k] == ';') {
        $k++;
        sequnce ();
    }
}

function statement () {
    global $k;
    global $i;
    global $myplotexpr;
    if (do_while ());
    else if (assgnmnt ());
    else if (plot ());
    else {
        echo $myplotexpr [$k];
        echo $myplotexpr [$i];
        echo $k;
        exit ( "error!!!!!");
    }
}

function do_while () {
    global $myplotexpr;
    global $a;
    global $i;
    global $k;
    global $while_count;
    global $myplotexpr;
    $i = $k;
    
    if (($myplotexpr [$i] == 'd') && ($myplotexpr [$i+1] == 'o')) {
        push ($i);
        
        $i+=2;
        $k+=2;
        

        sequnce ();
        
        if (!(($myplotexpr [$i] == 'w') && 
            ($myplotexpr [$i+1] == 'h') &&
            ($myplotexpr [$i+2] == 'i') &&
            ($myplotexpr [$i+3] == 'l') &&
            ($myplotexpr [$i+4] == 'e')))
                exit ("error!!!!!!!!!!");
        $i += 5;
        $k += 5;
        if (($myplotexpr [$i] == '$') && (($myplotexpr [$i+1] >= 'a') && ($myplotexpr [$i+1] <= 'z')))  {
            $ch = $myplotexpr [$i+1];
            $i+=2;
            $k+=2;
            if ($myplotexpr [$i] == '<') {
                $i+=1;
                $k+=1;
                $x = expr ();
                if ($x > 9)
                    exit ("error!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");
                $k = $i;
                
                if ($a [$ch] < $x) {
                    $i = pop ();
                    $k = $i;
                    if ($while_count > 16) 
                        exit ("errror!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");
                    $while_count++;
                    do_while ();
                    return true;
                }
                else {
                    pop ();
                    return true;
                }
            }
            else
                exit ("error!!!!!!!!!!!!!!!!!!!!!!!!!!!!!11");
        }
        else 
            exit ("error!!!!!!!!!!!!!!!!!!");
    }
    else
        return false;
}

function assgnmnt () {
    global $i;
    global $k;
    global $a;
    global $myplotexpr;
    
    $i = $k;

    if (($myplotexpr [$i] == '$') && (($myplotexpr [$i+1] >= 'a') && ($myplotexpr [$i+1] <= 'z'))) {
        $ch = $myplotexpr [$i+1];
        $i+=2;
        $k+=2;
        if ($myplotexpr [$i] == '=') {
            $i++;
            $a [$ch] = expr ();
            $k = $i;
            return true;
        }
        else {
            exit ( "error!!!!!!");
            return false;
        }
    }
    else
        return false;
}

function expr () {
    global $i;
    global $myplotexpr;
    $x = term ();
    if ($myplotexpr [$i] == '+') {
        $i++;
        $y = expr ();
        return $x + $y;
    }
    else if ($myplotexpr [$i] == '-') {
        $i++;
        $y = expr ();
        return $x - $y;
    }
    return $x;
}

function term () {
    global $i;
    global $myplotexpr;
    $x = factor ();
    if ($myplotexpr [$i] == '*') {
        $i++;
        $y = term ();
        return $x * $y;
    }
    else if ($myplotexpr [$i] == '/') {
        $i++;
        $y = term ();
        return $x / $y;
    }
    return $x;
}

function factor () {
    global $i;
    global $a;
    global $myplotexpr;
    if ($myplotexpr [$i] == '(') {
        $i++;
        $x = expr ();
        if ($myplotexpr [$i] == ')')
            $i++;
        else
            exit ( "error!");
        return $x;
    }
    else if (($myplotexpr [$i+0] == 'c') &&
            ($myplotexpr [$i+1] == 'o') &&
            ($myplotexpr [$i+2] == 's') && 
            ($myplotexpr [$i+3] == '(')) {
            $i += 4;
            $x = expr ();
            $y = cos ($x);
            if ($myplotexpr [$i] == ')') 
                $i++;
            else
                exit( "error!!");
            return $y;
    }
    else if (($myplotexpr [$i+0] == 's') &&
            ($myplotexpr [$i+1] == 'i') &&
            ($myplotexpr [$i+2] == 'n') && 
            ($myplotexpr [$i+3] == '(')) {
            $i += 4;
            $x = expr ();
            $y = sin ($x);
            if ($myplotexpr [$i] == ')') 
                $i++;
            else
                exit( "error!!");
            return $y;
    }
    else if (($myplotexpr [$i+0] == 't') &&
            ($myplotexpr [$i+1] == 'a') &&
            ($myplotexpr [$i+2] == 'n') && 
            ($myplotexpr [$i+3] == '(')) {
            $i += 4;
            $x = expr ();
            $y = tan ($x);
            if ($myplotexpr [$i] == ')') 
                $i++;
            else
                exit( "error!!");
            return $y;
    }
    else if (($myplotexpr [$i+0] == 'e') &&
            ($myplotexpr [$i+1] == 'x') &&
            ($myplotexpr [$i+2] == 'p') && 
            ($myplotexpr [$i+3] == '(')) {
            $i += 4;
            $x = expr ();
            $y = exp ($x);
            if ($myplotexpr [$i] == ')') 
                $i++;
            else
                exit( "error!!");
            return $y;
    }

    else if (($myplotexpr [$i] >= '0') && ($myplotexpr [$i] <= '9')) {
        $x = floatval(ord($myplotexpr [$i]) - ord('0'));
        $i++;
        return $x;
    }
    else if (($myplotexpr [$i] >= 'a') && ($myplotexpr [$i] <= 'z')) {
        $q = $a [$myplotexpr [$i]];
        $i++;
        return $q;
    }
    else 
        exit( "error!!!");

}


if ($flg)
    exec ("python3 compilertwitterimage.py");

?>