Nineteen

Its in the code above, try to read, and understad it, it does it 1000+ times........ Yup understand it now Very clever! Thank you very much Heaps cleaner than my old. $pa = $pv = 0; foreach ($scalePercents as $a => $value) { // Loop if picked $amount if ($pa != 0) { for ($i = $pa + 1; $i < $a; $i++) { if ($i == $amount) { $t1 = ($i - $pa) / ($a - $pa); $t2 = $t1 * ($value - $pv) + $pv; $scalePercents[$amount] = $t2; echo '** ' . $i . ' => ' . $t2 . '%<br />'; break 2; } } } // Set picked $amount $pa = $a; // Set picked $value $pv = $value; echo $a . ' => ' . $value . '%<br />'; }

This is what I have as part of the method to find the $key that does not exist. Any way this can be improved? It seems a bit more long winded than your example jskywalker. // $amount is the $key of the array $amount = 40; $scalePercents = array(); $scalePercents[5] = 90; $scalePercents[10] = 85; $scalePercents[20] = 70; $scalePercents[30] = 60; $scalePercents[50] = 50; $scalePercents[100] = 30; $scalePercents[200] = 20; $scalePercents[400] = 10; $scalePercents[1000] = 5; if (!array_key_exists($amount, $scalePercents)) { echo '<hr />Amount Does not exist <br />'; $percentKeys = array_keys($scalePercents); // $scaleRangeMin Value $amount = 1 or defaults to 100 $scaleRangeMin = ($scalePercents[1]) ? $scalePercents[1] : 100; // $scaleRangeMax Value $amount = $maxAmount or defaults to 100 $maxAmount = end($percentKeys); $scaleRangeMax = ($scalePercents[$maxAmount]) ? $scalePercents[$maxAmount] : 100; // Loop from $amount until 1 for ($iMin = $amount; $iMin > 1; $iMin--) { if (array_key_exists($iMin, $scalePercents)) { $scaleRangeMin = $scalePercents[$iMin]; break; } } // Loop from $amount until $maxAmount for ($iMax = $amount; $iMax < $maxAmount; $iMax++) { if (array_key_exists($iMax, $scalePercents)) { $scaleRangeMax = $scalePercents[$iMax]; break; } } echo 'Min Discount is: ' . $scaleRangeMin . '% of Price <br />'; echo 'Max Discount is: ' . $scaleRangeMax . '% of Price based on Quantity: ' . $amount . '<hr />'; // Calculate further $difference = $iMax - $iMin; $percentToScale = $scaleRangeMin - $scaleRangeMax; $eachPercent = ($difference > 0) ? $percentToScale / $difference : 1; $percentToSubtract = $amount - $iMin; $finalPercent = $scaleRangeMin - $eachPercent * $percentToSubtract; echo 'Difference: ' . $difference . '<br />Percent to Scale: ' . $percentToScale . '%'; echo '<br />Each Percent: ' . $eachPercent . '%<br />Quantity of: ' . $amount . ' is ' . $finalPercent . '%<hr />'; // Create $amount => $percent to calculate Price $scalePercents[$amount] = $finalPercent; } ------------------------------------------------------------------------------------------------------------------------------------------------------ Amount Does not exist Min Discount is: 60% of Price Max Discount is: 50% of Price based on Quantity: 40 ------------------------------------------------------------------------------------------------------------------------------------------------------ Difference: 20 Percent to Scale: 10% Each Percent: 0.5% Quantity of: 40 is 55% ------------------------------------------------------------------------------------------------------------------------------------------------------

Hey thank you for answering the question in my thread, I'm just wondering - How might you do this so rather than having a lot of calculations to populate the entire array (sometimes 1000+) how might you go about it to just calculate the one value? Eg: getValue($key); and have it return the value without having to loop and populate the entire thing?

Ok and rather than actually populating the whole array is there a way just to pull the one value please? Remembering that the "scale" changes between each populated min / max

How do you calculate that 4 will be 94, and 1000 will be 5? Is there a way to calculate it? That's the problem. I don't see a pattern. Sorry perhaps I haven't explained the problem as much. The array above is pre-populated by a user. Basically $key is a quantity and $value is a percent. So as the $key gets higher the $value gets lower. The user decides for x quantity will have x value and knows that as the quantity goes up the value will go down. What I need is based on the user's predefined array is to calculate what the missing $key would be based on what is present. So I calculated a return value of 97 based on the min / max and the difference of the $key 4. Eg: The process would calculate based on the Min being 1 (value of 100) and the Max being 11 (value of 90) therefore on a scale below: 1 2 3 |4| 5 6 7 8 9 10 11 100 99 98 |97| 96 95 94 93 92 94 90 If a user used a $key of say 116 then it would have to calcule based on a Min of 100 (value of 30) and a Max of 200 (value of 20)

So you're saying even if I know the min / max values (neighbors that exist) for a given $key and therefore knowing how many missing keys there are in between those min / max I can't calculate it?

Hi, Consider this array: Array ( [1] => 100 [11] => 90 [100] => 30 [200] => 20 [400] => 10 [1000] => 5 ) What I need help with is to write a function so that for example I could getValue($key) where $key = 4 and the function will first try to find a $key of 4, if found return the value. If it cannot find the $key = 4 then it will calculate what 4's value would have been based on scale. So in this case $key = 4 would return 97 Any ideas? It's a bit tricky to do without a lot of loops especially when they keys are not your usual index. Basically it needs to return a calculated value for a given $key based on the scale of it's upper / minimum neighbors.