Help needed

[JohnCarter]

The idea I want to do based on this logarithm http://www.wolframalpha.com/input/?i...100+log%28x%29

 

Basically the idea is, have a linear progression of reps (+1 power per 100 reps you have), until that line intersects (around 640~), then it would follow the curve, which would reduce the progression of rep power.

 

My problem is translating that into php

[Muddy_Funster]

your link doesn't work, and your information is a little sparse.  Is this a php coding quertion or a php math question?

[JohnCarter]

your link doesn't work, and your information is a little sparse.  Is this a php coding quertion or a php math question?

Oh I'm sorry I fixed the link http://www.wolframalpha.com/input/?i=x+%3D+100+log%28x%29

 

My problem is translating that into php. there's a natural logarithm function built in http://us3.php.net/log still at a loss how to apply the curve.

[Muddy_Funster]

So does something like the following help?

for($i=1;$i<=700;$i++){
  $rawLog= log($i);
  $roundedLog = round($x, 2);
  $roundedLogOneHundred = $y * 100;
  if($roundedLogOneHundred == $i){
    echo $roundedLogOneHundred." - ".$i." <<<--- This one!!<br>";
  }
  else{
    echo $roundedLogOneHundred." - ".$i."<br>";
  }
}

[Psycho]

I'm not sure what X represents in your example: the reps or reps/100 (i.e. "+1 power per 100 reps you have"). I think it is the latter. So, the simplest solution would be something like this:

function getPower($reps)
{
    $divVal = $reps/100;
    $logVal = max(100 * log($divVal), 1); //Max is needed to prevent 0 being returned @ 100 reps
    return min($divVal, $logVal);
}

//Test loop
for($rep=1; $rep<800; $rep++)
{
    $reps = $rep * 100;
    $power = getPower($reps);
    echo "Reps: {$reps}, Power: {$power}<br>\n";
}

Here is the part of the output from the test loop where you can see the transition take place:

 

Reps: 64500, Power: 645
Reps: 64600, Power: 646
Reps: 64700, Power: 647
Reps: 64800, Power: 647.389069635
Reps: 64900, Power: 647.54327167
Reps: 65000, Power: 647.697236289

Edited July 23, 2013 by Psycho

[JohnCarter]

 

I'm not sure what X represents in your example: the reps or reps/100 (i.e. "+1 power per 100 reps you have"). I think it is the latter. So, the simplest solution would be something like this:

function getPower($reps)
{
    $divVal = $reps/100;
    $logVal = max(100 * log($divVal), 1); //Max is needed to prevent 0 being returned @ 100 reps
    return min($divVal, $logVal);
}

//Test loop
for($rep=1; $rep<800; $rep++)
{
    $reps = $rep * 100;
    $power = getPower($reps);
    echo "Reps: {$reps}, Power: {$power}<br>\n";
}

Here is the part of the output from the test loop where you can see the transition take place:

Reps: 64500, Power: 645
Reps: 64600, Power: 646
Reps: 64700, Power: 647
Reps: 64800, Power: 647.389069635
Reps: 64900, Power: 647.54327167
Reps: 65000, Power: 647.697236289

Thanks for this, I will test it out later.