Save a value inside several lines to an array - php

Question

I'm doing a little php script and i have a form that saves several things on a txt.
I need to read all the lines and take the last value of each and put them all inside an array
I was thinking that i could do that with the explode function but i don't know how to implement it several times to sum all the values and get the average.
$nombre=$_POST['nombre'];
$edad=$_POST['edad'];
$email=$_POST['email'];
$importe=$_POST['importe'];
$nombre=$_POST['nombre'];
//this part writes each value of the form to a txt file separated by an " | "
// this is where I need help. I have to show the sum of all the $importe values in all of the lines in the txt
//
$miarchivo=fopen("resultados.txt","a");
if(!($miarchivo))
{
print("Imposible abrir archivo");
exit;
}
fputs($miarchivo," $nombre | $edad | $email | $importe \n" .PHP_EOL);
fclose($miarchivo);
//echo "<script>location.href='forma.php'</script>";
//This part only shows the values of the txt after the script ends
$miarchivo=fopen("resultados.txt","r");
if
(! ($miarchivo))
{
print("no hay resultados");
exit;
}
while(!feof($miarchivo)){
$linea=fgets($miarchivo,255);
print"$linea<BR>";
}
fclose($miarchivo);
I expect to get an array like:
tab [0] $importe //from line 0
tab [1] $importe //from line 2
tab [2] $importe //from line 3
tab [3] $importe //from line 4
So i can sum all of them and get the average in other variable

Answer 1

Export to array then take last value and store in array. Finally add the array and get the average result. Here is your code
while(!feof($miarchivo)){
$linea=fgets($miarchivo,255);
$quantityArray[] = end(explode('|',$linea));
}
$averageResult = array_sum($quantityArray)/count($quantityArray);

Answer 2

You need to make $linea[] an array by adding brackets like this.
while(!feof($miarchivo)){
$linea[]=fgets($miarchivo,255);
}
Then you can access each line like this...
$linea[0] = "line 1"
$linea[1] = "line 2"
if you need to print the current line, like you do in your while loop, you can add another temporary variable and print that like this...
$linea[] = $currentLine = fgets($miarchivo,255);
print($currentLine);

Answer 3

You don't need to store the values in an array to get an average. Unless you need to do something else with that array, it's just a waste of memory. You can sum and count the $importe values as you read the lines, and then calculate the average from those values at the end.
$count = $sum = 0;
while (($linea = fgetcsv($miarchivo, 0, '|')) !== false) {
$importe = trim($linea[3]);
$count++;
$sum += $importe;
}
if ($count) { // check count to prevent division by zero
$average = $sum / $count;
}