array question (I think!)

[DrMarie]

Let's see if I can explain what I am trying to do here.

I am creating a (for fun) diagnosis tool for my website. The idea is to have users fill out a checkbox list of things like vomiting, diarrhea, increased thirst, etc.

Then, that goes to a php file to be processed. What I want to do is something like this:

If vomiting is checked then add one point to each disease condition that includes vomiting such as pancreatitis, gastritis, etc.

Then, at the end, I want to add up each of the totals and display the top 5.

I'm pretty sure I need to store these as arrays, but I just can't get my head around how to do it!

Thanks, any help is appreciated!

Dr. Marie

[Chipzzz]

If you'll forgive a slightly off topic observation, that's a very worthwhile idea! You might think about writing it in a MySQL based CMS. The actual MySQL query is very few lines of code (two or three) and the database is then easily expanded to encompass a vast array of symptoms and diseases. It could even be enhanced to receive feedback and refine its diagnostics accordingly.

Just a thought,

Chipzzz

[tirna]

Yes, you will need an array of checkboxes to send to your php script.

In your html form you will need something like this:

 
<input type="checkbox" name="chkSymptoms[]" value="vomiting" />
<input type="checkbox" name="chkSymptoms[]" value="diarrhea" />
.
.
.

When you click the submit button an array named chkSymptoms with user selected values is sent to the server.

Your php code would look something like this:

//get the form data
$symptoms = $_POST['chkSymptoms'];  //store the checked symptoms in an array called $symptoms
 
foreach($symptoms as $value) {
    if($value == 'vomiting') {
        //do something here
    }
 
    if($value == 'diarrhea') {
        //do something else here
    }
}
 
//the rest of your processing 

You could use switch() but I'm trying to keep it fairly simple for now.

[NogDog]

If you go for a hard-coded, array-based solution, it could be something like:

$diseases = array(
   'pneumonia' => 0,
   'mumps' => 0,
   'tonsillitis' => 0
);
if($highTemperature)
{
   $diseases['pneumonia']++;
   $diseases['mumps']++;
   $diseases['tonsillitis']++;
}
if($swollenThroat)
{
   $diseases['mumps']++;
   $diseases['tonsillitis']++;
}
if($vomiting)
{
   $diseases['mumps']++;
}
arsort($diseases); // sort highest values to beginning of array
$bestGuess = key($diseases); // get the key of the first array element 

You could even add weighted amounts for each question, e.g.:

if($vomiting)
{
   $diseases['mumps'] += 2; // add 2 for significant symptom
} 

(I'm not doctor and am not claiming vomiting is a significant mumps symptom, just making an example. )

[DrMarie]

Ah, thanks guys!

Tirna...your way is pretty much how I was doing it, but I needed the foreach line.

You guys rock!

And Nog...You'd probably make a great doctor...a doctor has to be able to explain things to people and you do that well!

Nog, do you remember when I first came online a year ago and you helped me figure out how to learn php, mysql, etc? My site has been up and running for a while now and is really doing well!

[NogDog]

Ah, thanks guys!

Tirna...your way is pretty much how I was doing it, but I needed the foreach line.

You guys rock!

And Nog...You'd probably make a great doctor...a doctor has to be able to explain things to people and you do that well!

Nog, do you remember when I first came online a year ago and you helped me figure out how to learn php, mysql, etc? My site has been up and running for a while now and is really doing well!

I can't say I specifically remember that, but I recognized your user name, so I suppose there's something hidden in the musty file cabinets of my memory.

[DrMarie]

OK...I'm getting there. I've included my (very rudimentary) code here:

<?php
$symptom[]=$_POST['symptom'];


$num=count($symptom);


$disease = array(
   'pancreatitis' => 0,
   'gastritis' => 0,
   'kidney disease' => 0,
   'liver disease' => 0,
   'diabetes' => 0
);
if ($num==0)
  echo "Error";
else {
  foreach($symptom as $value) {
    if ($value=="vomiting") {
       $disease['pancreatitis']+=2; $disease['gastritis']+=2; $disease['kidney disease']+=1; $disease['liver disease']+=1;
    }
    if ($value=="polydypsia") {
       $disease['kidney disease']+=2; $disease['liver disease']+=1; $disease['diabetes']+=2;
    }
   
 
  }


arsort($disease);
print "Top matches:\r\n";

$top = key($disease);
print_r ($top);

}
?>

So, when I print $top I just get the number 1 choice. How do I print out the top 5?

[tirna]

One way of doing it would be :

<?php

$rows2display = 5;

for($i=0; $i<$rows2display; $i=$i+1) {
    echo 'Disease: '.key($disease[i]).' = '.$disease[i].' points.<br />';
}

?>

[DrMarie]

Ah, ok...thank you!

Bless you tirna for helping me out!

[DrMarie]

I'm getting errors:

Warning: key() [function.key]: Passed variable is not an array or object in /home/drmarie/public_html/tool.php on line 37
Disease: = points.

Warning: key() [function.key]: Passed variable is not an array or object in /home/drmarie/public_html/tool.php on line 37
Disease: = points.

Warning: key() [function.key]: Passed variable is not an array or object in /home/drmarie/public_html/tool.php on line 37
Disease: = points.

Warning: key() [function.key]: Passed variable is not an array or object in /home/drmarie/public_html/tool.php on line 37
Disease: = points.

Warning: key() [function.key]: Passed variable is not an array or object in /home/drmarie/public_html/tool.php on line 37
Disease: = points. 

I got a similar error when I tried to echo disease[1]. I think it has something to do with the fact that it is an associative array?

[tirna]

Sorry - I forgot it was an associative array and completely stuffed it up

This should work but there is probably an easier way:

<?php
$rows2display = 5;
$count = 0;
foreach($disease as $key => $value) {
   if($count < $rows2display) {
    echo 'Disease: '.$key.' = '.$value.' points.<br />';
  }
  $count = $count + 1
}
?>

[DrMarie]

Once again, thanks!

[tirna]

no problem happy to help.