PHP Error: Undefined offset error within foreach loop - php

Question

I have a csv file which I am trying to turn into a different structured array. First, I turn it into an array named all_data() constructed like this:
$data = file_get_contents($id . '.csv');
$data_array = explode("\n", $data);
foreach($data_array AS $data){
$all_data[] = explode("\t", $data);
}
results look like this:
array(5) {
[0]=>
array(2) {
[0]=>
string(10) "2012-11-14"
[1]=>
string(2) "10"
}
[1]=>
array(2) {
[0]=>
string(10) "2012-11-14"
[1]=>
string(2) "10"
}
[2]=>
array(2) {
[0]=>
string(10) "2012-11-14"
[1]=>
string(2) "10"
}
[3]=>
array(2) {
[0]=>
string(10) "2012-11-14"
[1]=>
string(2) "10"
}
[4]=>
array(1) {
[0]=>
string(0) ""
}
}
And then I turn it into im_arr() with the following code:
foreach($all_data as $key => $value){
$im_arr[$key][$value[0]] = $value[1];
}
The results:
array(5) {
[0]=>
array(1) {
["2012-11-14"]=>
string(2) "10"
}
[1]=>
array(1) {
["2012-11-14"]=>
string(2) "10"
}
[2]=>
array(1) {
["2012-11-14"]=>
string(2) "10"
}
[3]=>
array(1) {
["2012-11-14"]=>
string(2) "10"
}
[4]=>
array(1) {
[""]=>
NULL
}
}
And then, finally another foreach loop gives me the results I am looking for:
foreach ($im_arr as $val) {
foreach ($val as $key => $val2) {
$im_data[$key]=$val2;
}
}
With the result for im_data() being:
array(2) {
["2012-11-14"]=>
string(2) "10"
[""]=>
NULL
}
Which would be perfect, since the array im_data() is exactly what I would like to get out of all_data(). However, when I am trying to put this code in another part of the program it doesn't work, and I am thinking it might be because of the warnings I receive:
"PHP Notice: Undefined offset: 1 in ... on line 93"
Line 93 corresponds to this line:
$im_arr[$key][$value[0]] = $value[1];
Here is the complete part of the code:
$all_data = array();
$im_arr=array();
$data = file_get_contents($id . '.csv');
$data_array = explode("\n", $data);
foreach($data_array AS $data){
$all_data[] = explode("\t", $data);
}
foreach($all_data as $key => $value){
$im_arr[$key][$value[0]] = $value[1]; //the line for the error
}
$im_data=array();
foreach ($im_arr as $val) {
foreach ($val as $key => $val2) {
$im_data[$key]=$val2;
}
}
var_dump($im_data);
I know there are many many questions posted for this same error, but I couldn't figure out the problem with this particular piece of code.

Answer 1

This is the problem:
[4]=>
array(1) {
[0]=>
string(0) ""
}
Just check that the data is set, and isn't empty before adding them to $im_arr:
foreach ($all_data as $key => $value) {
if (isset($value[0]) && isset($value[1]) && !empty($value[0]) && !empty($value[1])) {
$im_arr[$key][$value[0]] = $value[1];
}
}

Answer 2

For every foreach i would pre-check if the first argument is an array
For instance ;
//Just add line below for every foreach (and add any required else statement if needed)
if(is_array($im_arr))
foreach ($im_arr as $val) {
if(is_array($val))
foreach ($val as $key => $val2) {
$im_data[$key]=$val2;
}
}