php - get specific column from txt file - columns separated irregularly - php

Question

I'm trying to read data to php from a txt file, I already was able to do this, but now it's kind of different.
the data file consists of rows looking like this:
10.09.16 0:05 16.7 16.8 16.7 70 11.2 3.2 ENE 0.27 6.4 ENE 16.7 16.4 16.4 --- 946.9 0.00 0.0 0 0.00 0 0.0 0.00 0.0 0.006 0.000 19.8 44 7.2 18.7 8.35 1.1146 15.6 0.00 112 2 100.0 5
10.09.16 0:10 16.7 16.8 16.7 70 11.2 4.8 E 0.40 6.4 E 16.7 16.4 16.4 --- 946.8 0.00 0.0 0 0.00 0 0.0 0.00 0.0 0.006 0.000 19.7 43 6.8 18.6 8.25 1.1151 15.6 0.00 115 2 100.0 5
as you see, the sepparation between the columns is not always the same, not for every column, and not even between rows.
now I have to get data from some specific columns.
can someone help me with this?
thanks!

Answer 1

You can read the file line by line, and then replace all the space by just one space (or other separator).
Then explode the line with the separator to get an array with each column.
Resource you could use:
Read file: check this answer
Replace space using str-replace
Explode in array using explode
Also, you could replace the space by some ; and use fgetcsv

Answer 2

Regular expressions are very powerful when it comes to matching and separating text sequences:
Simple approach if you don't know the number of columns in advance:
<?php
$input = <<<EOT
10.09.16 0:05 16.7 16.8 16.7 70 11.2 3.2 ENE 0.27 6.4 ENE 16.7 16.4 16.4 --- 946.9 0.00 0.0 0 0.00 0 0.0 0.00 0.0 0.006 0.000
10.09.16 0:10 16.7 16.8 16.7 70 11.2 4.8 E 0.40 6.4 E 16.7 16.4 16.4 --- 946.8 0.00 0.0 0 0.00 0 0.0 0.00 0.0 0.006 0.000
EOT;
$output = [];
foreach(explode("\n", $input) as $subject) {
if (trim($subject)) {
preg_match_all('/(?:([^\s]+)\s+)+/uU', $subject, $tokens);
$output[] = $tokens[1];
}
}
var_dump($output);
Much more elegant approach if you do know the number of columns in advance:
<?php
$input = <<<EOT
10.09.16 0:05 16.7 16.8 16.7 70 11.2 3.2 ENE 0.27 6.4 ENE 16.7 16.4 16.4 --- 946.9 0.00 0.0 0 0.00 0 0.0 0.00 0.0 0.006 0.000
10.09.16 0:10 16.7 16.8 16.7 70 11.2 4.8 E 0.40 6.4 E 16.7 16.4 16.4 --- 946.8 0.00 0.0 0 0.00 0 0.0 0.00 0.0 0.006 0.000
EOT;
preg_match_all('/(?:([^\s]+)\s+)+/uUm', $input, $output);
$output = array_chunk($output[1], 39);
var_dump($output);
I declared the input text inline to reduce complexity, you can read it from a file instead.
Both approaches will produce an identical output alone these lines:
array(2) {
[0] =>
array(39) {
[0] =>
string(8) "10.09.16"
[1] =>
string(4) "0:05"
[2] =>
...
[37] =>
string(5) "100.0"
[38] =>
string(1) "5"
}
[1] =>
array(39) {
[0] =>
string(8) "10.09.16"
[1] =>
string(4) "0:10"
[2] =>
...
[37] =>
string(5) "100.0"
[38] =>
string(1) "5"
}
}