Tough question

[jediwarrior82]

Ok, here's what I want to do and I want to know if its possible:

Create a php webpage that contains a recipe (see below) that allows users to input the number of people they intend on serving that dynamically updates the recipe -- after submitting the form-----
(Example)

Please enter number of people to be served (input box here)

Chicken Soup (default serves 5 people)

2 Cups of water
1 teaspoons of salt
12 oz of chicken

===========================

Now let's say they enter 10 people and click "submit"

I want the Chicken Soup recipe to update the quantities according to the amount inputted. So now the quanties should be:

4 cups of water
2 tablespoons of salt
1 lb and 8 oz of chicken

===========================

Notice the last ingredient how it does not display 24 oz but 1 lb and 8 oz... and I could actually do that for 4 cups too (=1 quart). Has anyone tackled something like that could lend me a hand or point me in the right direction? I suppose I'll need to create some variables and utilitize a lot of math functions. Any help is appreciated! Thanks

[sfullman]

you have three variables to pass to a function

existing unit
existing unit type
multiplier

so..

define(M_OZ,'ounces');

convert_measure(24, M_OZ,2){
//here you'd have a whole littany of different conversions

//notice I stored 1lb 8oz as 24, you have to store the raw data somewhere as a SINGLE unit (since that's always possible with decimals).

//you'll need a 4th parameter also for overriding expression, so that you can have 1lb be 16 oz if that's the best way to express

//finally you'll need to use the words "pinch" and "dash" when you go the other way. You'll have to technically define what a pinch and dash are :-)

}

function should return an array I believe, one the same unit, since M_OZ was passed, adn one with the preferred conversion:

$measure['equivalent']='48 ounces';
$measure['normal']='3 lb.';
return $measure;

I'm trying to give some pointers, the hard work is up to you and you'll learn something from approaching it. BTW you might search for cooking and baking measure conversion algorithms.

If you want other examples of "algorithms" search the code part of the forum, or seach the forum itself for "address parser" or "phone parser" which I recently did and submitted.

Bon Appetit,
Sam

[jediwarrior82]

Thanks for your input... yeah, most of the hard work is in the conversion tables.

Thanks again

[sidney]

heres one simple way to do it hope it helps

ive hard coded one recipe and a form it should run as is

  $recipe='5|default
2|Cups|of water 
1|teaspoons|of salt 
12|oz|of chicken';
$measure=array('oz'=>16,'Cups'=>4);
$measurechange=array('oz'=>'lb','Cups'=>'quarts');
$html='a recipe for ';
$recipelines=explode("\n",$recipe);
for($i=0;$i<count($recipelines);$i++)
	{
	$bits=explode('|',$recipelines[$i],3);
	if($i==0)
		{
		$default=$bits[0];
		$html.=(isset($_POST['sittings']) && $_POST['sittings']==(int)$_POST['sittings'])
			?$_POST['sittings'].' people<br><br>':$default.' people<br><br>';
		}
	if($i>0)
		{
		if(isset($_POST['sittings']) && $_POST['sittings']==(int)$_POST['sittings'])
			{
			$bits[0]=($bits[0]/$default)*$_POST['sittings'];
			if(isset($measure[$bits[1]]) && $bits[0]>=$measure[$bits[1]])
				{
				$front=floor($bits[0]/$measure[$bits[1]]);
				$end=round($bits[0]-($front*$measure[$bits[1]]),1);
				$bits[0]=(($front>0)?$front.' '.$measurechange[$bits[1]].' ':'').
					(($end>0)?$end.' '.$bits[1]:'');
				}
			else
				$bits[0].=' '.$bits[1];
			}
		else
			$bits[0].=' '.$bits[1];
		$html.=$bits[0].' '.$bits[2].'<br>';
		}
	}
$html.='<br><form action="'.$_SERVER['PHP_SELF'].'" method="post">
<input name="sittings" type="text" value="'.$default.'" size="4" maxlength="4">
<input name="update" type="submit" value="update recipe">';
echo $html; 

[sfullman]

If you really want to do this right, set up a database with tables on:

Ingredients -- list of possible ingredients and nutritional values per each

recipes -- overview of recipe and preparations

recipes_items -- relational link to ingredients table

the recipes_items table should have fields for:

idx (position on recipe, sometimes ingredients appear twice)
ingredientID
numericQuantity
units

If you're interested in help on this, I'd be glad to do it. This particular case I'd insist on charging something nominal, but very small. It would be cool to see something like that developed.

Sam

[jediwarrior82]

sidney: thanks for the code... i'll play around with it and see if i can something working for the moment

sfullman: hmmm, we may have to talk... I'd love to get this going but I just plain don't have the experience with PHP and I know setting up via a database would be a great idea.

[sfullman]

jedi,

no matter how you slice it (pun intended), this woud be a lot of work for you but a relational database truly is the way to go. If you enter your ingredients once, along with calories per unit, and enter a recipe as a series of related records tied to ingredients, you can immediately get calorie and nutriition information on the recipe. If you need help with setting up that structure, that's my expertise but you've definitely got a long row to hoe. However the benefits on the db approach would really be long term. PM me if you're interested.

Sam

[sidney]

jedi

i have cleaned up the code a little to make it easier to read

[drawmack]

here's an idea

db layout

table recipies
    id --> bigint auto increment
    name 
    serves

table ingredients
    id --> bigint auto increment
    recipie --> points to id in recipies table
    name
    servings --> int
    size --> enum(oz, tsp, tbspn, cup, etc.)

Now when you want to display a recipie just get the number to serve from the person then execute two queries

<?php
$sql = "SELECT * FROM recipies WHERE id=$id";
$query = mysql_query($sql);
$rcp = mysql_fetch_obj($query);
echo $rcp->name . "(serves " . $to_serve . ")<br />\n";
echo "<blockquote>\n";
$sql = "SELECT name, (amnt * " . $to_serve/$rcp->servings . ") as r_amnt, size from ingrdients WHERE recipie = $id";
$query = mysql_query($sql);
while(($row = mysql_fetch_object($query)) !== FALSE)
    echo $row->r_amnt . ' ' . $row->size . ' ' . $row->name . '<br />';
echo "</blockquote>\n";
?>

WARNING: This code was typed directly into the forum and probably contains errors.

This should do it for you without any conversion tables or anything. Does all the math right in the query. Then what you'll want to do is link the results page to a hard coded conversion table so when the person sees 200 tspns of an ingredient they can figure out what that is in pounds.

Hope that helps.

[jediwarrior82]

i really appreciate all the input --- thanks to all for your help!!