php实现将任意进制数转换成10进制的方法_PHP教程

php实现将任意进制数转换成10进制的方法

2020-09-20 14:42PHP教程网 PHP教程

这篇文章主要介绍了php实现将任意进制数转换成10进制的方法,涉及php数制转换的相关技巧,非常具有实用价值,需要的朋友可以参考下

本文实例讲述了php实现将任意进制数转换成10进制的方法。分享给大家供大家参考。具体如下：

php将任意进制的数转换成10进制，例如8进制转换成10进制，16进制转换成10进制

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									<?php

									# Show the steps involved in converting a number 

									# from any base (like octal or hex) to base 10

									# See below for examples, instructions and copyright

									function show_convert_to_base_10 ($number, $base)

									{

									 // If the number contains a decimal component

									 if (strstr ($number, '.'))

									 {

									  // Get the integer and decimal components

									  list ($integer, $decimal) = explode ('.', $number);

									 }

									 else

									 {

									  // The number is an integer

									  $integer = $number;

									 }

									  print "<b>Convert the base $base number $number to a

									  base 10 number:</b><blockquote>";

									  print "Convert the integer component ($integer) of the

									   number:<blockquote>";

									 // Compute the value of the integer component

									 // Loop through the integer digit by digit

									 // Reverse the number for easier handling

									 $integer = strrev ($integer);

									 $length = strlen ($integer);

									 for ($pos = 0; $pos < $length; ++$pos)

									 {

									  /*

									   PHP lets you treat strings and numbers like arrays

									   Specify an offset and get the character at that

									   position

									  */

									   $digit = $integer[$pos];

									  // Handle character values for digits

									  // (for bases greater than 10)

									  if (eregi ('[a-z]', $digit))

									  {

									   $digit_value =

									     (ord (strtolower ($digit))

									     - ord ('a')) + 10;

									    $digit = "$digit ($digit_value)";

									  }

									  else

									  {

									   $digit_value = $digit;

									  }

									  // Multiply the current digit by the radix

									  // raised to the power of the current position

									  $result = $digit_value * pow ($base, $pos);

									   print "Multiply the value of the digit at position

									    $pos by the value of the radix ($base) raised

									    to the power of the position ($pos):<br/>";

									   print "$digit * $base<sup>$pos</sup> = $result

									    <br/><br/>";

									   $sums[] = $result;

									 }

									 print '</blockquote>';

									 if (isset ($decimal))

									 {

									   print "Convert the decimal component (0.$decimal)

									   of the number:<blockquote>";

									  // Pad the number with a leading 0 so that we can

									  // start at position 1

									  $decimal = '0'.$decimal;

									  $length = strlen ($decimal);

									   for ($pos = 1; $pos < $length; ++$pos) {

									   $digit = $decimal[$pos];

									   // Handle character values for digits

									   // (for bases greater than 10)

									   if (eregi ('[a-z]', $digit))

									   {

									     $digit_value =

									     (ord (strtolower ($digit))

									     - ord ('a')) + 10;

									      $digit = "$digit ($digit_value)";

									   }

									   else

									   {

									     $digit_value = $digit;

									   }

									   // Multiply the current digit by the radix

									   // raised to the power of the current position

									   $result = $digit_value * pow (1/$base, $pos);

									    print "Multiply the value of the digit at

									    position $pos by the value of the 1/radix

									    ($base) raised to the power of the position

									    ($pos):<br/>";

									    print "$digit * 1/$base<sup>$pos</sup> =

									    $result<br/><br/>";

									    $sums[] = $result;

									  }

									  print '</blockquote>';

									 }

									 $sums = implode (' + ', $sums);

									 eval ("\$base_10_value = $sums;");

									  print "</blockquote>The value of the base $base number

									  $number in base 10 is $base_10_value. <br/>";

									  print "This number is derived from the sum of the values

									  of the previous operations ($sums). <br/> <br/>";

									}