Drawing

[Anon]

Hello Guys

can PHP makes graph for example if I want to draw the following function

f(x)=x² or
f(x)=log10(x) or
f(x)=sin(x)

OOzy

[Anon]

Yes .
PHP can do this work . But you must creat a new function to finish such work .
for f(x)=x² , we can use the following programe to carry out :

<?php
Header("Content-type: image/gif");

$color=0;
$imagesize_w=800;
$imagesize_h=600;
$filename="huanghm.gif";

$im=imagecreate($imagesize_w,$imagesize_h);
$white=ImageColorAllocate($im,255,255,255);
$black=ImageColorAllocate($im,0,0,0);
for($x=0.1;$x<$imagesize_w;$x+=.1)
{
$y=$x*$x;
if($y>$imagesize_h)break;
else{imagesetpixel($im,$x,$y,$black);}
}

ImageGif($im);
ImageDestroy($im);
?>

---

Notice :

The (x=0,y=0) is in the top-left screen .

My English is seek , I have to say sorry to you if you can't understand me .

[Anon]

Just a quick note on this. You have to have the gd library compilied into PHP before it will handle image manipluation.