Hello;
When I wrote a function to print out an array,
I could only print out the first two elements,( sometimes 8 out of 10 elements). What did I miss?
The problem seems to be the part
My understanding is (copied from stackoverflow): sizeof returns the size in memory of the passed element. By dividing the size of an array by a single element size, you get the elements count. On the other hand, when counting elements in an array: sizeof(a) / sizeof(a[0]) will still work as well. But my code does not! I saw this type online quite lot, but mine just does not work (Ubuntu 12.10, 64_bits kernel). Could anyone explain what is wrong with my code? Thanks a lot!
Hi all,
I am trying to create a function that return an array of integer based on the char parameter pass into the function. I.e.
func_a(char * str)
{
example str is equal to "1,2,3,4"
return an array of integers of 1,2,3,4
}
Please advise
regards
dwgi32 (2 Replies)
Hello. I'm working on a project that involves creating public/private keys server-side using openssl and using the public key in a Javascript application to encrypt sensitive data in form fields before transmission to the server. Using an SSL https server connection was not an option in this... (1 Reply)
I need to implement the following logic and need some expert help from UNIX community.
These are the steps in my Shell script.
1. Analyze a file.
2. Extract all the ID's in that file.
3. Use the ID's from #2 to run another filter on the file.
I've implemented # 1 and 2 using... (3 Replies)
Hi !
I'm looking for a way to transform certain floating point numbers in a one-line, variable length file to integers.
I can do this in a crude way with sed :
sed -e 's/0\.\(\):/\1:/g' -e 's/0\.0\(\):/\1:/g' -e 's/1\.000:/100:/g' myfile ... but this doesn't handle the rounding correctly.
... (3 Replies)
As Brendan O'Conner writes in this blog, mawk is near 8 times faster than gawk, so I am going to give mawk a go, but I got errors when trying to print the length of an array in mawk using length() function, is it not supported in mawk? or there's another way to get the length of an array in mawk?
... (3 Replies)
I would be grateful if someone could help me. I am trying to write a .sh script in UNIX.
I have the following code;
User=john
User=james
User=ian
User=martin
for x in ${User}
do
print ${#x}
done
This produces the following output;
4
5
3
6 (12 Replies)
Hello All,
I have this script that does stuff like "starting, stopping & restarting" a Daemon Process running on my machine...
My main question is why in part of my code (which you will see below) does the Array Length (i.e. ${#PIDS} )
return "1" when I know the Array is empty..?
Here is... (17 Replies)
Does anyone know how to find length of multi dimension array
of following type
A Afor simple array I is to do
for (i in A)n++ to find length of array but if it is multi dimension how to find the length ? (2 Replies)
Hi there,
I'm listing files and sorting them. When I try to get length of array variable in which these files are stored I get 1 as value. That's weird.
files_info="$(find $input_dir -name "*_CHR$i.info" | sort )"
printf ${#files_info}"\n" #print length
#--loop through... (6 Replies)
Discussion started by: genome
6 Replies
LEARN ABOUT PHP
array_map
ARRAY_MAP(3) 1 ARRAY_MAP(3)array_map - Applies the callback to the elements of the given arraysSYNOPSIS
array array_map (callable $callback, array $array1, [array $...])
DESCRIPTION array_map(3) returns an array containing all the elements of $array1 after applying the $callback function to each one. The number of
parameters that the $callback function accepts should match the number of arrays passed to the array_map(3)PARAMETERS
o $callback
- Callback function to run for each element in each array.
o $array1
- An array to run through the $callback function.
o $...
- Variable list of array arguments to run through the $callback function.
RETURN VALUES
Returns an array containing all the elements of $array1 after applying the $callback function to each one.
EXAMPLES
Example #1
array_map(3) example
<?php
function cube($n)
{
return($n * $n * $n);
}
$a = array(1, 2, 3, 4, 5);
$b = array_map("cube", $a);
print_r($b);
?>
This makes $b have:
Array
(
[0] => 1
[1] => 8
[2] => 27
[3] => 64
[4] => 125
)
Example #2
array_map(3) using a lambda function (as of PHP 5.3.0)
<?php
$func = function($value) {
return $value * 2;
};
print_r(array_map($func, range(1, 5)));
?>
Array
(
[0] => 2
[1] => 4
[2] => 6
[3] => 8
[4] => 10
)
Example #3
array_map(3) - using more arrays
<?php
function show_Spanish($n, $m)
{
return("The number $n is called $m in Spanish");
}
function map_Spanish($n, $m)
{
return(array($n => $m));
}
$a = array(1, 2, 3, 4, 5);
$b = array("uno", "dos", "tres", "cuatro", "cinco");
$c = array_map("show_Spanish", $a, $b);
print_r($c);
$d = array_map("map_Spanish", $a , $b);
print_r($d);
?>
The above example will output:
// printout of $c
Array
(
[0] => The number 1 is called uno in Spanish
[1] => The number 2 is called dos in Spanish
[2] => The number 3 is called tres in Spanish
[3] => The number 4 is called cuatro in Spanish
[4] => The number 5 is called cinco in Spanish
)
// printout of $d
Array
(
[0] => Array
(
[1] => uno
)
[1] => Array
(
[2] => dos
)
[2] => Array
(
[3] => tres
)
[3] => Array
(
[4] => cuatro
)
[4] => Array
(
[5] => cinco
)
)
Usually when using two or more arrays, they should be of equal length because the callback function is applied in parallel to the corre-
sponding elements. If the arrays are of unequal length, shorter ones will be extended with empty elements to match the length of the long-
est.
An interesting use of this function is to construct an array of arrays, which can be easily performed by using NULL as the name of the
callback function
Example #4
Creating an array of arrays
<?php
$a = array(1, 2, 3, 4, 5);
$b = array("one", "two", "three", "four", "five");
$c = array("uno", "dos", "tres", "cuatro", "cinco");
$d = array_map(null, $a, $b, $c);
print_r($d);
?>
The above example will output:
Array
(
[0] => Array
(
[0] => 1
[1] => one
[2] => uno
)
[1] => Array
(
[0] => 2
[1] => two
[2] => dos
)
[2] => Array
(
[0] => 3
[1] => three
[2] => tres
)
[3] => Array
(
[0] => 4
[1] => four
[2] => cuatro
)
[4] => Array
(
[0] => 5
[1] => five
[2] => cinco
)
)
If the array argument contains string keys then the returned array will contain string keys if and only if exactly one array is passed. If
more than one argument is passed then the returned array always has integer keys.
Example #5
array_map(3) - with string keys
<?php
$arr = array("stringkey" => "value");
function cb1($a) {
return array ($a);
}
function cb2($a, $b) {
return array ($a, $b);
}
var_dump(array_map("cb1", $arr));
var_dump(array_map("cb2", $arr, $arr));
var_dump(array_map(null, $arr));
var_dump(array_map(null, $arr, $arr));
?>
The above example will output:
array(1) {
["stringkey"]=>
array(1) {
[0]=>
string(5) "value"
}
}
array(1) {
[0]=>
array(2) {
[0]=>
string(5) "value"
[1]=>
string(5) "value"
}
}
array(1) {
["stringkey"]=>
string(5) "value"
}
array(1) {
[0]=>
array(2) {
[0]=>
string(5) "value"
[1]=>
string(5) "value"
}
}
SEE ALSO array_filter(3), array_reduce(3), array_walk(3), information about the callback type.
PHP Documentation Group ARRAY_MAP(3)