Question

在php中有一个增加

的功能

数组

中后续值的值两次（* 2）

列基于初始值？

$beta = array(
array('5', '1''1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1'),
array('5','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2'),
array('5','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2'),
array('5','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2'),
array('5','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2'),
array('5','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2'),
array('5','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2'),
array('5','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2'),
array('5','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2'),
array('5','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2','2')

);

/*Example: '5' will be '10' (5*2 =10 and output 10 to web)
         '2' will be '4'  (2*2 = 4 and output 4 to web)
The next '2' will be '16' (4*2 = 8 and output 8 to web)
The next '2' will be '32' (8*2 = 16 and output 16 to web)
And so forth? */

此外，还有一种更简单的方法来构建这个数组，因为我坚信存在，但不是在构造方面太复杂，以至于菜鸟不会理解它，再次感谢。

[免责声明：我花了3天时间试图理解阵列，我现在理解了它们;然而，我仍然是新手，我在尝试操纵我的数组中的值并将它们输出到网络时遇到了一些问题。我仍然非常确定我有很多东西需要阅读和学习，所以请不要浪费，我只是需要一些帮助，在这本C ++书中发现了这个问题：

[http://books.google.com/books?id=4Fn_P7tdOZgC&pg=PT424&lpg=PT424&dq=subsequent+++column+is+twice+the+value&source=bl&ots=gSvQ_LhxoI&sig=dG_Ilf1iLO86lqX936cT1PpkPc8&hl=en&ei=OEEBS_eODYyotgOFtJD3CQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CAgQ6AEwAA#v=onepage&q=subsequent%20%20%20column%20is%20twice%20the%20value&f=false][1]

Answer 1

您可以尝试array_map：

<?php
function increase($n) {
     return is_array($n) ? array_map('increase', $n) : $n * 2;
}

$new_beta = array_map("increase", $beta);

至于构建阵列，还有其他方法可以这样做，但我相信这是最实用和最干净的。

Answer 2

以下是本书该部分中每个问题的答案，享受！

<?php

// Declare an array alpha of 10 rows and 20 columns of type int
// Initialise the array alpha to 0
$alpha = array(array());
for($i = 0; $i < 10; $i++)
{
    for($j = 0; $j < 20; $j++)
    {
        $alpha[$i][$j] = 0;
    }
}

// Store 1 in the first row and 2 in the remaining rows
for($i = 0; $i < 10; $i++)
{
    for($j = 0; $j < 20; $j++)
    {
        if($i == 0)
        {
            $alpha[$i][$j] = 1;
        }
        else
        {
            $alpha[$i][$j] = 2;
        }
    }
}

// Store 5 in the first column, and make sure that the value in
// each subsequent column is twice the value in the previous column
// (Beware this doesn't build off the initial value of 5 in the first
// column but the previously set values above)
for($i = 0; $i < 10; $i++)
{
    for($j = 0; $j < 20; $j++)
    {
        if($j == 0)
        {
            $alpha[$i][$j] = 5;
        }
        else
        {
            if($j - 1 >= 1)
            {
                $alpha[$i][$j] = $alpha[$i][$j-1] * 2;
            }
        }
    }
}

// Print the array alpha one row per line
print "Printing the array alpha one row per line:<br/>";
for($i = 0; $i < 10; $i++)
{
    for($j = 0; $j < 20; $j++)
    {
        print "[". $alpha[$i][$j] ."] ";
    }

    print "<br/>";
}

print "<br/>";

// Print the array alpha one column per line
print "Printing the array alpha one column per line:<br/>";
for($j = 0; $j < 20; $j++)
{
    for($i = 0; $i < 10; $i++)
    {
        print "[". $alpha[$i][$j] ."] ";
    }

    print "<br/>";
}

?>

php数组输出问题

2 个答案: