Im working on a browser game where i need to handle energy. The user spends and gets energy but i have come across an issue that i have tried to fix, When a user has for example 20 Energy and he does something that spends 30 energy it's going through and ofcourse i understand because i am checking the value to not go below 0 like this
if ( 0 < $resultenergy[0]['energy'])
This means that unless the users energy is at 0 he can spend whatever he want. What would be a better way to check the data so it alerts when "trying" to go under 0 ? I appreciate all help and if you have an idea of a different approach im all ears.
Do the calculation once.
$remaining_energy = $current_energy - $energy_cost;
Then check the result, and act accordingly.
if ($remaining_energy >= 0) {
$current_energy = $remaining_energy;
// do whatever required the energy
// send the client a succes indicator
} else {
// don't change current energy
// send the client an error indicator
}
You could subtract and then evaluate. e.g.
if ( 0 < $resultenergy[0]['energy'] - $energyCost) {
$resultenergy[0]['energy'] = $resultenergy[0]['energy'] - $energyCost;
return true
} else {
return false;
}
$energyCost is the cost of whatever action they're trying to do.
Related
I have a trivial question for you but I can not deal with the matches myself.
more precisely - I have a problem with writing a condition that will only be fulfilled when specific parameters occur.
say, I have three thresholds: 2000, 15325, 500000
each of them has an appropriate level
user points are, for example: 16,000
I want it to search for the appropriate level and assign it to the user after reaching the threshold
I unfortunately have a problem with the condition of fulfilling the activity, because the condition
user points> = point threshold
shows me all levels, but
user points <= point threshold
it does not show anything, it does not fulfill the assumption of the script
function chooseLevel($dbh) {
$userPoints = getPoints($dbh, 3);
$levels = getLevels($dbh);
foreach($levels as $required) {
if($userPoints >= $required["points"]) {
$level = $required["level"];
}
}
return $level;
}
I'm having a small problem. In a class called reservation that has an attribute called reserve , which in the database is a tinyint(4), and an attribute kamp, which is int(10). I'm trying to do this:
if ($this->kamp == 387 || $this->kamp == 388 || $this->kamp == 389) {
$this->reserve = 0;
} else {
$this->reserve = 1;
}
Now my problem is, the code ALWAYS jumps straight to the else bracket. Even when I'm 100% sure $this->kamp is 387, 388 or 389.
Does this have anything to do with datatypes or am I missing something? I think the problem lies within this piece of code, since in my database there are objects showing up where reserve = 1 and the kamp is one of the three numbers I mentioned.
Thanks!
i think this will work for you.
$val = intval($this->kamp);
and then print or echo for result it will giving you value or not ?
let me know if i can help you more.
I have a golf league of 40 individuals. We all throw money in a pot and pay out the first 6 places based on final score.
If there were no ties the pay out would be simple but often we have, for example, 2 people tied for first place, 3 people tied for second, 1 person alone in third, etc. The variations seem endless.
I've been trying to automate the calculated payouts for each place using PHP but have not been successful. Any suggestions, help, or pointing in the right direction would be much appreciated. I noticed that someone else tried to ask a similar question on this site but was not successful in framing the question. I'll try to do a better job.
Here is some data I've been playing around with:
$playerNumber=40;
$totalPoints=100;
Payouts:
$pointsFirst=0.6*$totalPoints;
$pointsSecond=0.2*$totalPoints;
$pointsThird=0.15*$totalPoints;
$pointsFourth=0.03*$totalPoints;
$pointsFifth=0.02*$totalPoints;
$pointsSixth=0.01*$totalPoints;
For the example given above and to pay out six places, we would calculate the payouts as follows:
If two people are tied for first place, we add first and second place points and divide by two.
If three people are tied for second place, we add third, fourth and fifth place points and divide by three.
If one person is alone in third, this person would win sixth place points.
I can count the number of players who are in or tied for a certain place.
$countFirst=2;
$countSecond=3;
$countThird=1;
$countFourth=2;
$countFifth=1;
$countSixth=2;
In this example the player scores would be 72, 72, 73, 73, 73, 74, 75, 75, 76, 77, 77.
At first I thought this was an application for nested arrays. Then I thought perhaps using arrays, array slice, etc, may be a way to go. Each time I end up in the woods. I'm not seeing the logic.
I have used conditional statements for paying out three places but to pay out six places with this method puts me deep in the woods.
Example of payout to three places using conditional statements:
$pointsFirst=0.5*$totalPoints;
$pointsSecond=0.3*$totalPoints;
$pointsThird=0.2*$totalPoints;
if($countFirst>2) {
$ptsA=round($totalPoints/$countFirst,2);
}
elseif($countFirst==2) {
$ptsA=round(($pointsFirst+$pointsSecond)/2,2);
if($countSecond>1) {
$ptsB=round($pointsThird/$countSecond,2);
}
elseif($countSecond==1) {
$ptsB=round($pointsThird,2);
}
}
elseif($countFirst==1) {
$ptsA=round($pointsFirst,2);
if($countSecond>1) {
$ptsB=round(($pointsSecond+$pointsThird)/2,2);
}
elseif($countSecond==1) {
$ptsB=round($pointsSecond,2);
if($countThird>1) {
$ptsC=round($pointsThird/$countThird,2);
}
elseif($countThird==1) {
$ptsC=round($pointsThird,2);
}
}
}
I hope I have been clear in my request. I'll be glad to clarify anything. If anyone has any ideas on how to efficiently automate a payout calculation to six places I will be eternally grateful. Thank-you! Mike
Per request:
$scores=array();
$scores[0]=72;
$scores[1]=72;
$scores[2]=73;
$scores[3]=73;
$scores[4]=73;
$scores[5]=74;
$scores[6]=75;
$scores[7]=75;
$scores[8]=76;
$scores[9]=77;
$scores[10]=77;
$payout=array();
$payout[0]=0.6*$totalPoints;
$payout[1]=0.2*$totalPoints;
$payout[2]=0.15*$totalPoints;
$payout[3]=0.03*$totalPoints;
$payout[4]=0.02*$totalPoints;
$payout[5]=0.01*$totalPoints;
$countScores=array();
$countScores[0]=$countFirst;
$countScores[1]=$countSecond;
$countScores[2]=$countThird;
$countScores[3]=$countFourth;
$countScores[4]=$countFifth;
$countScores[5]=$countSixth;
First, there is a problem with your Payouts. If you add them up you get 1.01 not 1
0.6 (1st) + 0.2 (2nd ) + 0.15 (3rd) + 0.03 (4th) + 0.02 (5th) + 0.01 (6th) = 1.01
Second, it is easier if you make your Payouts and Counts into arrays -
change these -
$pointsFirst=0.6*$totalPoints;
$pointsSecond=0.2*$totalPoints;
$pointsThird=0.15*$totalPoints;
$pointsFourth=0.03*$totalPoints;
$pointsFifth=0.02*$totalPoints;
$pointsSixth=0.01*$totalPoints;
$countFirst=2;
$countSecond=3;
$countThird=1;
$countFourth=2;
$countFifth=1;
$countSixth=2;
to these
$payout=array();
$payout[0]=0.6*$totalPoints;
$payout[1]=0.2*$totalPoints;
$payout[2]=0.15*$totalPoints;
$payout[3]=0.03*$totalPoints;
$payout[4]=0.02*$totalPoints;
$payout[5]=0.01*$totalPoints;
$count=array();
$count[0]=2;
$count[1]=3;
$count[2]=1;
$count[3]=2;
$count[4]=1;
$count[5]=2;
Here is the start of one way to do it. Although I would eventually change this into a function so that I can use it again with different payouts, and number of places (see phpfiddle examples below)
I see this in 4 steps-
Step 1
// Add together the payments if there are ties - ie. 2 tied for first $payout[0]+$payout[1], etc
$payout_groups = array(); // start a payout array
$payout_groups_key = 0; // array key count
$payout_groups_count = 0; // array counter, use to match the $count array values
for($w=0;$w<count($payout);$w++){ //
if(array_key_exists($payout_groups_key,$payout_groups)){
$payout_groups[$payout_groups_key] += $payout[$w]; // if there are ties, add them together
}
else{
$payout_groups[$payout_groups_key] = $payout[$w]; // else set a new payout level
}
$payout_groups_count++; // increase the counter
if($payout_groups_count == $count[$payout_groups_key]){ // if we merged all the ties, set a new array key and restart the counter
$payout_groups_key++;
$payout_groups_count = 0;
}
}
Step 2
// basic counter to get how many placers/winners. This makes it possible to have ties for 6th (last) place
$x = 0;
$y = 0;
while($y < count($payout)){
$y += $count[$x]; // the $count array values until we reach the amount of places/payouts
$x++;
}
Step 3
// Create array for winnings per placing
$winnings = array(); // start an array
$placings_count = 0; //
$placings_counter = 0;
for($z=0;$z<$y;$z++){
$winnings[$z] = $payout_groups[$placings_count]/$count[$placings_count];
$placings_counter++;
if($placings_counter == $count[$placings_count]){
$placings_count++;
$placings_counter = 0;
}
}
Step 4
// Assign winnings to scorecard
$scoreboard = array();
for($t=0;$t<count($winnings);$t++){
$scoreboard[$t]['score'] = $scores[$t];
$scoreboard[$t]['payout'] = $winnings[$t];
}
You can see this using your defined values at - http://phpfiddle.org/main/code/a1g-qu0
Using the same code above, I changed the payout amounts, and increased it to 7th places - http://phpfiddle.org/main/code/uxi-qgt
I need to go through an array containing points in a map and check their distance from one another. I need to count how many nodes are within 200m and 50m of each one. It works fine for smaller amounts of values. However when I tried to run more values through it (around 4000 for scalability testing) an error occurs saying that I have reached the maximum execution time of 300 seconds. It needs to be able to handle at least this much within 300 seconds if possible.
I have read around and found out that there is a way to disable/change this limit, but I would like to know if there is a simpler way of executing the following code so that the time it takes to run it will decrease.
for($i=0;$i<=count($data)-1;$i++)
{
$amount200a=0;
$amount200p=0;
$amount50a=0;
$amount50p=0;
$distance;
for($_i=0;$_i<=count($data)-1;$_i++)
{
$distance=0;
if($data[$i][0]===$data[$_i][0])
{
}
else
{
//echo "Comparing ".$data[$i][0]." and ".$data[$_i][0]." ";
$lat_a = $data[$i][1] * PI()/180;
$lat_b = $data[$_i][1] * PI()/180;
$long_a = $data[$i][2] * PI()/180;
$long_b = $data[$_i][2] * PI()/180;
$distance =
acos(
sin($lat_a ) * sin($lat_b) +
cos($lat_a) * cos($lat_b) * cos($long_b - $long_a)
) * 6371;
$distance*=1000;
if ($distance<=50)
{
$amount50a++;
$amount200a++;
}
else if ($distance<=200)
{
$amount200a++;
}
}
}
$amount200p=100*number_format($amount200a/count($data),2,'.','');
$amount50p=100*number_format($amount50a/count($data),2,'.','');
/*
$dist[$i][0]=$data[$i][0];
$dist[$i][1]=$amount200a;
$dist[$i][2]=$amount200p;
$dist[$i][3]=$amount50a;
$dist[$i][4]=$amount50p;
//*/
$dist.=$data[$i][0]."&&".$amount200a."&&".$amount200p."&&".$amount50a."&&".$amount50p."%%";
}
Index 0 contains the unique ID of each node, 1 contains the latitude of each node and
index 2 contains the longitude of each node.
The error occurs at the second for loop inside the first loop. This loop is the one comparing the selected map node to other nodes. I am also using the Haversine Formula.
first of all, you are performing in big O notation: O(data^2), which is gonna be slow as hell , and really, either there are 2 possible solutions. Find a proven algorithm that solves the same problem in a better time. Or if you cant, start moving stuff out of the innner for loop, and mathmatically prove if you can convert the inner for loop to mostly simple calculations, which is often something you can do.
after some rewriting, I see some possiblities:
If $data is not a SPLFixedArray (which has a FAR Better access time, ) then make it. since you are accessing that data so many times (4000^2)*2.
secound, write cleaner code. although the optizmier will do its best, if you dont try either to minize the code (which only makes it more readable), then it might not be able to do it as well as possible.
and move intermediate results out of the loops, also something like the size of the array.
Currently you're checking all points against all other points, where in fact you only need to check the current point against all remaining points. The distance from A to B is the same as the distance from B to A, so why calculate it twice?
I would probably make an adjacent array that counts how many nodes are within range of each other, and increment pairs of entries in that array after I've calculated that two nodes are within range of each other.
You should probably come up with a very fast approximation of the distance that can be used to disregard as many nodes as possible before calculating the real distance (which is never going to be super fast).
Generally speaking, beyond algorithmic optimisations, the basic rules of optimisation are:
Don't any processing that you don't have to do: Like not multiplying $distance by 1000. Just change the values you're testing against from 20 and 50 to 0.02 and 0.05, respectively.
Don't call any function more often than you have to: You only need to call count($data) once before any processing starts.
Don't calculate constant values more than once: PI()/180, for example.
Move all possible processing outside of loops. I.e. precalculate as much as possible.
Another minor point which will make your code a little easier to read:
for( $i = 0; $i <= count( $data ) - 1; $i++ ) is the same as:
for( $i = 0; $i < count( $data ); $i++ )
Try this:
$max = count($data);
$CONST_PI = PI() / 180;
for($i=0;$i<$max;$i++)
{
$amount200a=0;
$amount50a=0;
$long_a = $data[$i][2] * $CONST_PI;
$lat_a = $data[$i][1] * $CONST_PI;
for($_i=0;$_i<=$max;$_i++)
//or use for($_i=($i+1);$_i<=$max;$_i++) if you did not need to calculate already calculated in other direction
{
$distance=0;
if($data[$i][0]===$data[$_i][0]) continue;
$lat_b = $data[$_i][1] * $CONST_PI;
$long_b = $data[$_i][2] * $CONST_PI;
$distance =
acos(
sin($lat_a ) * sin($lat_b) +
cos($lat_a) * cos($lat_b) * cos($long_b - $long_a)
) * 6371;
if ($distance<=0.2)
{
$amount200a++;
if ($distance<=0.05)
{
$amount50a++;
}
}
} // for %_i
$amount200p=100*number_format($amount200a/$max,2,'.','');
$amount50p=100*number_format($amount50a/$max,2,'.','');
$dist.=$data[$i][0]."&&".$amount200a."&&".$amount200p."&&".$amount50a."&&".$amount50p."%%";
} // for $i
It will be better to read I think and if you change the commented out line of the for $_i it will be faster at all :)
I am running subscriptions on my website.
I have a 1,3,6 and 12 months of subscription, and I would like the user to be able to change that subscription whenever they feel like.
However, I need to calculate the amount of money the user had to pay had he or she signed up for the shorter term, rather the relatively cheap,longer one.
I made this function optimized_subscription_total($active_sub_time,$arr_sub_values) so that it returns that sum of money exactly.
<?php
function optimized_subscription_total($active_sub_time,$arr_sub_values)
{
// This function takes a row from the DB where prices for each period of time usage is listed. there are prices for 1 month, 3 months,6 and 12 months.
// when the user has subscribed for 12 months, and the user asks for a refund, after they used 9 months and 6 days for example, the system treats the refund as if they subscribed for (in months) COST_6 + COST_3 + (COST_1/30)*6
// the result of the function is then subtracted from the amount they actually paid and is considered the refund.
// $arr_sub_values is the associative row from the DB, containing the prices
// $active_sub_time is measured in months and is a double
$result=0;
while(($active_sub_time-12)>=0)
{
$active_sub_time-=12;
$result+=($arr_subscription_values['COST_12']);
}
while(($active_sub_time-6)>=0)
{
$active_sub_time-=6;
$result+=($arr_subscription_values['COST_6']);
}
while(($active_sub_time-3)>=0)
{
$active_sub_time-=3;
$result+=($arr_subscription_values['COST_3']);
}
while(($active_sub_time-1)>=0)
{
$active_sub_time-=1;
$result+=($arr_subscription_values['COST_1']);
}
if($active_sub_time>0)
$result+=($active_sub_time)*($arr_subscription_values['COST_1']);
return $result;
}
$datetime1 = date_create('2009-12-11');
$datetime2 = date_create('2010-11-09');
$interval = date_diff($datetime1, $datetime2);
$num_of_months = ($interval->format('%y'))*12+($interval->format('%m'))+($interval->format('%a'))/30;
echo "<br />";
$v = array('COST_1'=>'3.99','COST_3'=>'9.99','COST_6'=>'15.99','COST_12'=>'25.99');
echo "OPT value for $num_of_months months=" . optimized_subscription_total($num_of_months, $v);
?>
Strangely I get the bug appearing only after 7 to 10 times after refreshing this code.
So I got:
OPT value for 10 months=M.97
as a result here. I think I need to get a float number, no ?
I was expecting the result of the function that should be "OPT value for 10 months=29.97", as it should take COST_6 + COST_3 + COST_1... but I get that weird M.97, and sometimes things like POKHHHG.97
I would change the logic to the following and see if error is still produced. I think this is a little bit more clear and easy to debug. It is the same as your though just explained differently.
while($active_sub_time>=12)
{
$active_sub_time-=12;
$result+=($arr_subscription_values['COST_12']);
}
while($active_sub_time>=6)
{
$active_sub_time-=6;
$result+=($arr_subscription_values['COST_6']);
}
while($active_sub_time>=3)
{
$active_sub_time-=3;
$result+=($arr_subscription_values['COST_3']);
}
while($active_sub_time>=1)
{
$active_sub_time-=1;
$result+=($arr_subscription_values['COST_1']);
}
What I would also do is added debug cod at the top inside function.
echo "<br>$active_sub_time" // debug code include at the top
This will give you an idea, if any garbage being is being sent to the function itself.
Also I would add this test function in all while blocks if the above does not resolve the issue.
if (!is_numeric($result))
{
echo"<br> Bug occurred";break; // print other values if necessary
}