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Determining pivot


stijn0713

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I want to determine the pivot in a table and therefore i need to find the key of the lowest value in a certain 'row' of a two dim array.

 

I came up with this:

 

$laagstegetal = $tabel[$m-1][3];

for ($i = 2; $i <$n; $i++){
if ($tabel[$m-1][$i] < $laagstegetal){
	$laagstegetal = $tabel[$m-1][$i];
	}
$indexGrootsteMC = array_search($laagstegetal, $tabel[$m-1]);
echo $laagstegetal;	
}

 

Here, $laagstegetal is supposed to contain the lowest value of the row $m -1. However, $tabel[$m-1][$i] doesn't overwrite the value holded by $laagstegetal but always adds it for some reason.  In the end it holds like : -7500-7500-8200-10500-10500-10500-10500-10500

instead of -10500. What is wrong in my thinking and how could i fix it?

 

Thanks in advance

 

 

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There's not enough code here to be sure, because for starters I'm not sure why you've initialized your for loop the way you have.  Why start $i at 2?  what is $n?

That aside, it probably doesn't have anything directly to do with the error you're seeing.  Is the line

 

$laagstegetal = $tabel[$m-1][3];

 

The only spot where you initalize $laagstegetal?

 

Did you retype this code into the forum window or did you copy/paste?  A cause of your issue isn't jumping out at me, but if you have retyped it rather than copy/paste, having

 

$laagstegetal .= $tabel[$m-1][$i];

 

instead of:

 

$laagstegetal = $tabel[$m-1][$i];

 

certainly would cause the issue you're seeing

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There's not enough code here to be sure, because for starters I'm not sure why you've initialized your for loop the way you have.  Why start $i at 2?  what is $n?

 

I should start with $i = 3. Because my tables are so that in row $m-1 ($m being the number of rows), column 0,1,2 are always empty so i can start with column 3.

 

That aside, it probably doesn't have anything directly to do with the error you're seeing.  Is the line

 

$laagstegetal = $tabel[$m-1][3];

 

The only spot where you initalize $laagstegetal?

.

Yes.

Did you retype this code into the forum window or did you copy/paste?  A cause of your issue isn't jumping out at me, but if you have retyped it rather than copy/paste, having

 

$laagstegetal .= $tabel[$m-1][$i];

 

instead of:

 

$laagstegetal = $tabel[$m-1][$i];

 

. Nope that's not the problem
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try thowing in an echo statement in that loop so you can see the value of each one as it passes through and how it affects  $laagstegetal.  Is the value being appended to it?  Prepended?  Is every value being attached or just some of them?  A quick echo will help determine that an narrow it down

 

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Ahh.....so it wasn't really adding the values, they were just all output to the screen in succession so it seemed like it :shrug:

I always bracket my echo statements with <br/> to make it easier to delineate the information it's trying to tell me

 

Looking at the returns, at least you know it's sticking with the lowest compared value like you intended :)

 

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