[Apoc]

Time to ask a question. As a bit of a sub project / idea i have (like all my ideas i start and never complete.. whatdidido springs to mind).

But getting back to the question, i have a file, which in the script is processed and inserted into a table. (the file is massive, as its data about my PC temp / voltages).

What i want to do is get this data and be able to select by temp source (i.e. mobo or cpu) and by date and produce a graph. I have hacked some code and got it almost working, but i think the code i have hacked was doing something else (%ages).

So what is the best way to graph say the following data as a line graph?

TEMP
45.5
46.0
47.5
44.5
45.5
45.0
44.0
50.0
49.5
48.5
46.5
39.0

The code i have is the following:

PHP Code:

<?php
//.. Above this is the processing file bit and 
//..the DB reult bit (selecting from the DB)
//..That all works fine
 
header ("Content-type: image/jpeg"); 

// --- Need to figure out width and size of the font. 
$font = 1; 
$fontHeight = ImageFontHeight ($font); 
$fontWidth = ImageFontWidth ($font); 

// --- This is the number of rows 
$numAnswers = mysql_num_rows ($resulters); 
echo $numanswers; 
// --- This is the size of the image 
$width = 1200; //300 
$height = 300; //200 
$image = ImageCreate ($width, $height); 

// --- Get the width of each item. 
$widthPerItem = ($width / $numAnswers); 

$white = ImageColorAllocate ($image, 255, 255, 255); 
$red = ImageColorAllocate ($image, 255, 0, 0); 

//$top = 10; 
$top = 70; 
$bottom = $height - (2 * $fontHeight); 
$maxbarheight = $bottom - $top; 
$item = 0; 
$gap = 5; 
while ($row = mysql_fetch_array ($resulters, MYSQL_ASSOC)) { 

// --- Calcualate the pixel height 
if ($mostVotes > 0) { 
$newtop = $bottom - 
(($row["Tmp2"] * $maxbarheight) / $mostVotes); 
} else { 
$newtop = $bottom; 
} 

// --- Draw each bar graph 
ImageFilledRectangle ($image, 
($item * $widthPerItem) + ($gap / 2), 
$newtop, 
($item * $widthPerItem) + ($widthPerItem - ($gap / 2)), 
$bottom, $red); 

$text = $row["Time"]; 

ImageString ($image, $font, 
$item * $widthPerItem, 
$bottom + $fontHeight, $text, $red); 

$item++; 
} 


ImageJpeg ($image); 
ImageDestroy ($image); 
?>

The bit of the code that bothers me is:

PHP Code:

//$top = 10; 
$top = 70; 
$bottom = $height - (2 * $fontHeight); 
$maxbarheight = $bottom - $top; 
$item = 0; 
$gap = 5; 
while ($row = mysql_fetch_array ($resulters, MYSQL_ASSOC)) { 

// --- Calcualate the pixel height 
if ($mostVotes > 0) { 
$newtop = $bottom - 
(($row["Tmp2"] * $maxbarheight) / $mostVotes); 
} else { 
$newtop = $bottom; 
} 

As i can't work out what its doing (was for some polling thing), it doesn't work with a small pic size i.e. 400*80 which i want (sig time) but will work (or seems to work) with picture sizes of 15000*100. The data is taken every 5min so thats about 300 values of data per day.

Any ideas on how to do this, i.e. plat on make a line graph of the data?

Cheers

[fie]

it would have help to have samples of the fscked up images

[Apoc]

Been having a play and altered the code substantially to whats above (instead of hacking i made my own version). what it ddoes now is select the array from mysql, and plot a line from point n to n+1 and then loops for all the variables. this is nearly working. When its done i'll post the code incase its of use to anyone else.

[Apoc]

Sorted.. what you guys think?

[snipe]

Originally Posted by Apoc

Sorted.. what you guys think?

Have you checked out JPGraph at all? Its *amazing*.

http://www.aditus.nu/jpgraph/

I have used it for many things, very quick and easy, and super-flexible.