


Description of decimal system conversion function, decimalsystem_PHP tutorial
Decimal system conversion function description, decimalsystem
1, decimal system conversion function description
1, decimal to binary decbin () function, the following example
echo decbin(12); //Output 1100
echo decbin(26); //Output 11010
decbin
(PHP 3, PHP 4, PHP 5)
decbin -- Convert decimal to binary
Description
string decbin ( int number )
Returns a string containing the binary representation of the given number parameter. The maximum value that can be converted is 4294967295 in decimal, which results in a string of 32 ones.
2, decimal to octal decoct() function
echo decoct(15); //Output 17
echo decoct(264); //Output 410
decoct
(PHP 3, PHP 4, PHP 5)
decoct -- Convert decimal to octal
Description
string decoct (int number)
Returns a string containing the octal value of the given number parameter express. The maximum value that can be converted is 4294967295 in decimal, which results in "37777777777".
3, decimal to hexadecimal dechex() function
echo dechex(10); //Output a
echo dechex(47); //Output 2f
dechex
(PHP 3, PHP 4, PHP 5)
dechex -- Convert decimal to hexadecimal
Description
string dechex (int number)
Returns a string containing The hexadecimal representation of the given number argument. The maximum value that can be converted is 4294967295 in decimal, which results in "ffffffff".
2. Description of binary system conversion function
1. Bin2hex() function from binary to hexadecimal system
$binary = "11111001";
$hex = dechex(bindec($binary));
echo $hex;//Output f9
bin2hex
(PHP 3 >= 3.0.9, PHP 4, PHP 5)
bin2hex -- Convert binary data to hexadecimal representation
Description
string bin2hex ( string str )
Returns an ASCII string, which is the hexadecimal representation of the parameter str. Conversion uses byte mode, with the high nibble taking precedence.
2, binary to decimal conversion bindec() function
echo bindec('110011'); //Output 51
echo bindec('000110011' ); //Output 51
echo bindec('111'); //Output 7
bindec
(PHP 3, PHP 4, PHP 5)
bindec -- Binary to decimal conversion
Description
number bindec (string binary_string)
Returns the decimal equivalent of the binary number represented by the binary_string parameter.
bindec() converts a binary number into an integer. The largest number that can be converted is 31 digits, or 2147483647 in decimal. Starting with PHP 4.1.0, this function can handle large values, in which case it returns a float type.
Three, octal system conversion function description
Octal to decimal octdec() function
echo octdec('77'); //Output 63
echo octdec(decoct(45)); //Output 45
octdec
(PHP 3, PHP 4, PHP 5)
octdec -- Convert octal to decimal
Instructions
number octdec (string octal_string)
Returns the decimal equivalent of the octal number represented by the octal_string parameter. The largest value that can be converted is 17777777777 or 2147483647 in decimal. Starting with PHP 4.1.0, this function can handle large numbers, in which case it returns a float type.
4. Description of hexadecimal conversion function
Hexadecimal to decimal hexdec() function
var_dump(hexdec("See" ));
var_dump(hexdec("ee"));
// both print "int(238)"
var_dump(hexdec("that")); // print "int (10)"
var_dump(hexdec("a0")); // print "int(160)"
hexdec
(PHP 3, PHP 4, PHP 5)
hexdec -- ten Convert hexadecimal to decimal
Description
number hexdec ( string hex_string )
Returns the decimal number equivalent to the hexadecimal number represented by the hex_string parameter. hexdec() Converts a hexadecimal string to a decimal number. The maximum value that can be converted is 7ffffffff, which is 2147483647 in decimal. Starting with PHP 4.1.0, this function can handle large numbers, in which case it returns a float type.
hexdec() Replaces all non-hexadecimal characters encountered with 0. This way, all zeros on the left are ignored, but zeros on the right are included in the value.
Five, arbitrary base_convert() function
$hexadecimal = 'A37334';
echo base_convert($hexadecimal, 16, 2);/ /Output 101000110111001100110100
base_convert
(PHP 3 >= 3.0.6, PHP 4, PHP 5)
base_convert -- Convert numbers between any bases
Description
string base_convert (string number, int frombase, int tobase)
Returns a string containing the representation of number in tobase base. The base of number itself is specified by frombase. Both frombase and tobase can only be between 2 and 36 (inclusive). Numbers above decimal are represented by the letters a-z, such as a for 10, b for 11, and z for 35.
Here we mainly organize PHP hexadecimal conversion functions to facilitate development and search. Please refer to the PHP manual for relevant specific function descriptions. Please pay attention to the next issue of the Chinese character encoding research series.
The JS decimal to other base code is as follows var m = 10;document.write(m.toString(2) + "
"); // Displayed as 1010 binary document.write(m.toString(8) + "
"); // Displayed as 12 octal document.write(m.toString(10) + "
"); // Displayed as 10 decimal document.write(m.toString(16) + "
"); // Displayed as a, the hexadecimal PHP conversion function is as follows: bindec() — Convert binary to decimal
decbin() — Convert decimal to binary
dechex() — Convert decimal to hexadecimal
decoct() — Convert decimal to octal
hexdec() — Convert hexadecimal to decimal
octdec() — Convert octal to decimal
base_convert()– Instructions for converting numbers between arbitrary systems are as follows: 1. Description of the decimal system conversion function
1. The decimal to binary decbin() function, the following example echo decbin(12); //Output 1100
echo decbin(26); //Output 11010
decbin
(PHP 3, PHP 4, PHP 5)
decbin -- Convert decimal to binary
Instructions
string decbin ( int number )
Returns a string containing the binary representation of the given number parameter. The maximum value that can be converted is 4294967295 in decimal, which results in a string of 32 ones. 2. Convert decimal to octal decoct() function echo decoct(15); //Output 17
echo decoct(264); //Output 410
decoct
(PHP 3, PHP 4, PHP 5)
decoct -- Convert decimal to octal
Description
string decoct ( int number )
Returns a string containing the octal representation of the given number parameter. The maximum value that can be converted is 4294967295 in decimal, which results in "37777777777". 3. Convert decimal to hexadecimal dechex() function echo dechex(10); //Output a
echo dechex(47); //Output 2f
dechex
(PHP 3, PHP 4, PHP 5)
dechex -- Convert decimal to hexadecimal
Description
string dechex ( int number )
Returns a string containing the hexadecimal representation of the given number parameter. The maximum value that can be converted is 4294967295 in decimal, which results in "ffffffff". 2. Description of binary system conversion function
1, binary to hexadecimal conversion bin2hex() function $binary = "11111001";
$hex = dechex(bindec($binary));
echo $hex;//Output f9
bin2hex
(PHP 3 >= 3.0.9, PHP 4, PHP 5)
bin2hex -- will...the rest of the text>>
package com.test.numsys;
import java.util.*;
/**
* Numeric conversion decimal binary octal hexadecimal
*/
public class NumSys {
public static void main(String[] args) {
NumSys ns = new NumSys();
System.out.println("decimal 100 Convert to binary: " + ns.decimalToBinary(100));//1100100
System.out.println("Convert binary 1100100 to octal: " + ns.binaryToOctal(1100100));// 144
System.out.println("Binary 10110000011101 is converted to hexadecimal: " + ns.binaryToHex("10110000011101")); //2C1D
System.out.println ("Decimal 100 is converted to octal: " + ns.DecimalToOctal(100));
System.out.println("Decimal 15400 is converted to hexadecimal: " + ns.DecimalToHex(15400));
}
//The conversion of decimal to binary is not implemented
public long decimalToBinary(int a) {
long binary = 0L;
int[] binaryArr = new int[64];
int i = 0;
do {
binaryArr[i] = a%2;
a = a/2;
i ++;
} while(a != 0);
String s = "";
for(int j = binaryArr.length-1; j>=0; j--) {
s+=binaryArr[j] + "";
}
binary = Integer.parseInt(s);
return binary;
}
// Binary to octal conversion
public String binaryToOctal(long a) {
String octal = "";
String s = a +"";
char [] c_temp = (a+"").toCharArray ();
int temp = 3 - c_temp.length%3;
for(int i = 0; i
}
char[] c2 = s.toCharArray();
List
for(int i = 0 ; i String stemp = c...The rest of the text>>

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