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A large summary of PHP mathematical operation functions (classics worth collecting), PHP is worth collecting
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A large summary of PHP mathematical operation functions (classics worth collecting), PHP worth collecting_PHP tutorial

Jul 12, 2016 am 08:55 AM
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A large summary of PHP mathematical operation functions (classics worth collecting), PHP is worth collecting

This article summarizes and analyzes PHP mathematical operation functions. Share it with everyone for your reference, the details are as follows:

1. Description of commonly used functions:

Abs: Get the absolute value.

Acos: Get the arc cosine value.

Asin: Get the arcsine value.

Atan: Get the arctangent value.

Atan2: Calculate the arc tangent of a two number.

base_convert: The carry method for converting numbers.

BinDec: Convert binary to decimal.

Ceil: Calculate the smallest integer greater than the specified number.

Cos: Cosine calculation.

DecBin: Convert decimal to binary.

DecHex: Convert decimal to hexadecimal.

DecOct: Convert decimal to octal.

Exp: The power of the natural logarithm e.

Floor: Calculate the largest integer less than the specified number.

getrandmax: the maximum value of random numbers.

HexDec: Convert hexadecimal to decimal.

Log: Natural logarithm value.

Log10: Log value of 10 base.

max: Get the maximum value.

min: Get the minimum value.

mt_rand: Get a random value.

mt_srand: Configure random number seed.

mt_getrandmax: The maximum value of random number.

number_format: Format number string.

OctDec: Convert octal to decimal.

pi: Pi.

pow: power.

rand: Get a random value.

round: Rounded.

Sin: Sine calculation.

Sqrt: Square root.

srand: configure random number seed.

Tan: Tangent calculation.

2. Function analysis is as follows:

Abs
Get the absolute value.
Syntax: mixed abs(mixed number);
Return value: Mixed type data
Function type: Mathematical operation
Content description: Returns the absolute value of parameter number. If number is a multiple-precision floating-point number, the return value is also a multiple-precision floating-point number; for other types, the return type is an integer.

Acos
Get the arc cosine value.
Syntax: float acos(float arg);
Return value: floating point number
Function type: Mathematical operation
Content description: Returns the arc cosine of parameter arg.
Reference: asin() atan()

Asin
Get the arcsine value.
Syntax: float asin(float arg);
Return value: floating point number
Function type: Mathematical operation
Content description: Returns the arc sine value (arc sine) of parameter arg.
Reference: acos() atan()

Atan
Get the arctangent value.
Syntax: float atan(float arg);
Return value: floating point number
Function type: Mathematical operation
Content description: Returns the arc tangent of parameter arg (arc tangent).
Reference: acos() asin()

Atan2
Calculate the arctangent of a two number.
Syntax: float atan2(float y, float x);
Return value: floating point number
Function type: Mathematical operation
Content description: This function is used to calculate the arc tangent of two numbers y and x. The calculation result is similar to atan()'s calculation of y/x, but this function will affect the result due to the positive and negative signs of x and y. The return value of this function must fall between positive and negative pi (-PI <= (value) ≶= PI)
Reference acos() atan() asin()

base_convert
Convert the carry method of numbers.
Syntax: string base_convert(string number, int frombase, int tobase);
Return value: string
Function type: Mathematical operation
Content Description: This function converts the numeric string number from carry from base to carry from tobase. This formula can handle carry modes from binary to hexadecimal. Before the decimal place, it is represented by numbers, and after the decimal place is exceeded, it is represented by English letters. For example, the sequence of hexadecimal single digits is 123456789abcdef, and the sequence of 10 is the seventeenth, and then one digit is carried forward. In hexadecimal a is the tenth, b is the eleventh, z is the thirty-sixth, and 10 is the thirty-seventh, then the carry is carried out.

Usage Example

This example converts a hexadecimal string into a binary string

<&#63;php
$binary = base_convert($hexadecimal, 16, 2);
echo "十六進(jìn)位字符串"$hexadecimal"轉(zhuǎn)成二進(jìn)位為"$binary"。";
&#63;>

BinDec
Convert binary to decimal.
Syntax: int bindec(string binary_string);
Return value: integer
Function type: Mathematical operation
Content description: This function converts a binary digit string into a decimal integer. Since PHP uses 32-bit signed integers for calculations, the maximum decimal number it can handle is 2147483647, which is 1111111111111111111111111111111 (31 ones) in binary.
Reference: DecBin()

Ceil
Computes the smallest integer greater than the specified number.
Syntax: int ceil(float number);
Return value: integer
Function type: Mathematical operation
Content description: This function is used to calculate the smallest integer larger than the floating point parameter number.

Usage Example

The return value in this example is 4.

<&#63;php
$nextint=ceil(3.14);
echo $nextint;
&#63;> 

Reference: Floor() round()

Cos
余弦計(jì)算。
語法: float cos(float arg);
返回值: 浮點(diǎn)數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算參數(shù) arg 的余弦值 (cosine)。
參考: Sin() Tan()

DecBin
十進(jìn)位轉(zhuǎn)二進(jìn)位。
語法: string decbin(int number);
返回值: 字符串
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)將十進(jìn)位數(shù)字轉(zhuǎn)成二進(jìn)位字符串。由于 PHP 使用 32 位有正負(fù)號整數(shù)計(jì)算,能處理的最大十進(jìn)位數(shù)字為 2147483647,也就是二進(jìn)位數(shù)字的 1111111111111111111111111111111 (31 個(gè) 1)。
參考: BinDec()

DecHex
十進(jìn)位轉(zhuǎn)十六進(jìn)位。
語法: string dechex(int number);
返回值: 字符串
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)將十進(jìn)位數(shù)字轉(zhuǎn)成十六進(jìn)位字符串。由于 PHP 使用 32 位有正負(fù)號整數(shù)計(jì)算,能處理的最大十進(jìn)位數(shù)字為 2147483647,也就是十六進(jìn)位數(shù)字 7fffffff。
參考: HexDec()

DecOct
十進(jìn)位轉(zhuǎn)八進(jìn)位。
語法: string decoct(int number);
返回值: 字符串
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)將十進(jìn)位數(shù)字轉(zhuǎn)成八進(jìn)位字符串。由于 PHP 使用 32 位有正負(fù)號整數(shù)計(jì)算,能處理的最大十進(jìn)位數(shù)字為 2147483647,也就是八進(jìn)位數(shù)字 17777777777。
參考: OctDec()

Exp
自然對數(shù) e 的次方值。
語法: float exp(float arg);
返回值: 浮點(diǎn)數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算自然對數(shù) (natural logarithm) 的 arg 次方值。
參考: pow() Log()

Floor
計(jì)算小于指定數(shù)的最大整數(shù)。
語法: int floor(float number);
返回值: 整數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)用來計(jì)算比浮點(diǎn)參數(shù) number 小的最大整數(shù)。

使用范例

本例返回值為 3。

<&#63;php
$lastint=floor(3.14);
echo $lastint;
&#63;> 

參考: Ceil() round()

getrandmax
亂數(shù)的最大值。
語法: int getrandmax(void);
返回值: 整數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算亂數(shù)函數(shù) rand() 可能取得的取得的最大亂數(shù)值。本函數(shù)不需參數(shù)。
參考: rand() srand() mt_rand() mt_srand() mt_getrandmax()

HexDec
十六進(jìn)位轉(zhuǎn)十進(jìn)位。
語法: int hexdec(string hex_string);
返回值: 整數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)將十六進(jìn)位字符串轉(zhuǎn)成十進(jìn)位數(shù)字。由于 PHP 使用 32 位有正負(fù)號整數(shù)計(jì)算,能處理的最大十六進(jìn)位數(shù)字為 7fffffff,也就是十進(jìn)位數(shù)字的 2147483647。
參考: DecHex()

Log
自然對數(shù)值。
語法: float log(float arg);
返回值: 浮點(diǎn)數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算參數(shù) arg 的自然對數(shù) (natural logarithm) 值。

Log10
10 基底的對數(shù)值。
語法: float log10(float arg);
返回值: 浮點(diǎn)數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算參數(shù) arg 的 10 基底對數(shù)值。

max
取得最大值。
語法: mixed max(mixed arg1, mixed arg2 .... mixed argn);
返回值: 混合類型資料
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算參數(shù)間的最大值。若第一個(gè)參數(shù)是數(shù)字?jǐn)?shù)組,則會(huì)找出該數(shù)組的最大數(shù)字。若第一個(gè)參數(shù)非數(shù)組,則需二個(gè)以上的參數(shù)。這些數(shù)字可以是整數(shù)、倍精確數(shù)或數(shù)字字符串的類型。參數(shù)的數(shù)目不限,視用戶的需求而定。在計(jì)算時(shí),只要有一個(gè)參數(shù)是倍精確數(shù),本函數(shù)會(huì)將所有的參數(shù)都轉(zhuǎn)成倍精確數(shù),并返回倍精確數(shù)。若參數(shù)只有整數(shù)及數(shù)字字符串,則會(huì)將所有的參數(shù)轉(zhuǎn)換成整數(shù),并返回整數(shù)。
參考: min()

min
取得最小值。
語法: mixed min(mixed arg1, mixed arg2 .... mixed argn);
返回值: 混合類型資料
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算參數(shù)間的最小值。若第一個(gè)參數(shù)是數(shù)字?jǐn)?shù)組,則會(huì)找出該數(shù)組的最小數(shù)字。若第一個(gè)參數(shù)非數(shù)組,則需二個(gè)以上的參數(shù)。這些數(shù)字可以是整數(shù)、倍精確數(shù)或數(shù)字字符串的類型。參數(shù)的數(shù)目不限,視用戶的需求而定。在計(jì)算時(shí),只要有一個(gè)參數(shù)是倍精確數(shù),本函數(shù)會(huì)將所有的參數(shù)都轉(zhuǎn)成倍精確數(shù),并返回倍精確數(shù)。若參數(shù)只有整數(shù)及數(shù)字字符串,則會(huì)將所有的參數(shù)轉(zhuǎn)換成整數(shù),并返回整數(shù)。
參考: max()

mt_rand
取得亂數(shù)值。
語法: int mt_rand([int min], [int max]);
返回值: 整數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)不使用一般常用的 libc 來計(jì)算亂數(shù)值,而是使用計(jì)算速度至少快四倍的馬其賽特旋轉(zhuǎn) (Mersenne Twister) 演算法來計(jì)算亂數(shù)值。有關(guān)馬特賽特旋轉(zhuǎn)演算法可在松本真的 http://www.math.keio.ac.jp/~matumoto/emt.html 找到更多的相關(guān)信息,最佳化的原始程序則在 http://www.scp.syr.edu/~marc/hawk/twister.html。若沒有指定亂數(shù)的最大及最小范圍,本函數(shù)會(huì)自動(dòng)的從 0 到 RAND_MAX 中取一個(gè)亂數(shù)。若有指定 min 及 max 的參數(shù),則從指定參數(shù)中取一個(gè)數(shù)字,例如 mt_rand(38, 49) 則會(huì)從 38 到 49 之間取一個(gè)亂數(shù)值。值得注意的是為使亂數(shù)的亂度最大,每次在取亂數(shù)之前最好使用 mt_srand() 以配置新的亂數(shù)種子。
參考: rand() srand() getrandmax() mt_srand() mt_getrandmax()

mt_srand
配置亂數(shù)種子。
語法: void mt_srand(int seed);
返回值: 無
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)傳入?yún)?shù) seed 后,配置亂數(shù)的種子。值得注意的是參數(shù) seed 值最好也是隨機(jī)出現(xiàn)的數(shù)字,例如利用加入時(shí)間做為變量的來源就是不錯(cuò)的方法,或者開發(fā)其它的硬體周邊界面可取得更好的亂數(shù)。

使用范例

本例加入時(shí)間的因素,以執(zhí)行時(shí)的百萬分之一秒當(dāng)亂數(shù)種子

<&#63;php
mt_srand((double)microtime()*1000000);
$randval = mt_rand();
echo $randval;
&#63;> 

參考: rand() srand() getrandmax() mt_rand() mt_getrandmax()

mt_getrandmax
亂數(shù)的最大值。
語法: int mt_getrandmax(void);
返回值: 整數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算亂數(shù)函數(shù) mt_rand() 可能取得的取得的最大亂數(shù)值。本函數(shù)不需參數(shù)。
參考: rand() srand() getrandmax() mt_srand() mt_rand()

number_format
格式化數(shù)字字符串。
語法: string number_format(float number, int [decimals], string [dec_point], string [thousands_sep]);
返回值: 字符串
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)用來將浮點(diǎn)參數(shù) number 格式化。若沒加參數(shù) decimals 則返回的字符串只要整數(shù)部份,加了此參數(shù)才依參數(shù)指定的小數(shù)點(diǎn)位數(shù)返回。參數(shù) dec_point 表示小數(shù)點(diǎn)的表示方式方法,默認(rèn)值是 ".",若需要轉(zhuǎn)換成其它的小數(shù)點(diǎn)就可以在這個(gè)參數(shù)改掉。參數(shù) thousands_sep 為整數(shù)部份每三位的分隔符號,默認(rèn)值是 ","。本函數(shù)最特別的地方就是參數(shù)數(shù)目,最少要有一個(gè),也就是欲格式化的字符串;也可以有二個(gè)或者四個(gè)參數(shù),但不能用三個(gè)參數(shù)。值得注意的是指定小數(shù)點(diǎn)的位數(shù)之后的數(shù)字直接舍棄,沒有四舍五入的情形。

使用范例

<&#63;php
$short_pi = "3.14159";
$my_pi = number_format($short_pi, 2);
echo $my_pi."n"; // 3.14
$foo = 850017.9021;
$new_foo = number_format($foo, 3, ".", " ");
echo $new_foo."n"; // 850 017.902
&#63;>

OctDec
八進(jìn)位轉(zhuǎn)十進(jìn)位。
語法: string decoct(int number);
返回值: 字符串
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)將八進(jìn)位字符串轉(zhuǎn)成十進(jìn)位數(shù)字。由于 PHP 使用 32 位有正負(fù)號整數(shù)計(jì)算,能處理最大的八進(jìn)位數(shù)字為 17777777777,也就是十進(jìn)位數(shù)字的 2147483647。
參考: DecOct()

pi
圓周率。
語法: double pi(void);
返回值: 倍精確數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)返回圓周率。不需輸入?yún)?shù)。

pow
次方。
語法: float pow(float base, float exp);
返回值: 浮點(diǎn)數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算次方值。參數(shù) base 為基底,exp 為冪數(shù)。

使用范例

<&#63;php
print(pow(2,3)); // 8
print(pow(5,4)); // 625
&#63;> 

參考: Log10() Exp()

rand
取得隨機(jī)數(shù)值。
語法: int rand([int min], [int max]);
返回值: 整數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)用來取得隨機(jī)數(shù)值。若沒有指定隨機(jī)數(shù)的最大及最小范圍,本函數(shù)會(huì)自動(dòng)的從 0 到 RAND_MAX 中取一個(gè)隨機(jī)數(shù)。若有指定 min 及 max 的參數(shù),則從指定參數(shù)中取一個(gè)數(shù)字。例如 rand(38, 49) 則會(huì)從 38 到 49 之間取一個(gè)隨機(jī)數(shù)值,UNIX 系統(tǒng)包含 49、Win32 系統(tǒng)不包含 49 ([email=zkimmel@earthlink.net]zkimmel@earthlink.net[/email] 10-May-1999)。值得注意的是為使隨機(jī)數(shù)的亂度最大,每次在取隨機(jī)數(shù)之前最好使用 srand() 以配置新的隨機(jī)數(shù)種子。
參考: srand() getrandmax() mt_rand() mt_srand() mt_getrandmax()

round
四舍五入。
語法: double round(double val);
返回值: 倍精確數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)用來將數(shù)字小數(shù)點(diǎn)后四舍五入。

使用范例

<&#63;php
$foo1 = round(3.4);
$foo2 = round(3.5);
$foo3 = round(3.6);
echo "round(3.4): ".$foo1."<br>n";
echo "round(3.5): ".$foo2."<br>n";
echo "round(3.6): ".$foo3;
&#63;>

參考: Ceil() Floor()

Sin
正弦計(jì)算。
語法: float sin(float arg);
返回值: 浮點(diǎn)數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算參數(shù) arg 的正弦值 (sine)。
參考: Cos() Tan()

Sqrt
開平方根。
語法: float sqrt(float arg);
返回值: 浮點(diǎn)數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)將參數(shù) arg 開平方根。

srand
配置隨機(jī)數(shù)種子。
語法: void srand(int seed);
返回值: 無
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)傳入?yún)?shù) seed 后,配置隨機(jī)數(shù)的種子。值得注意的是參數(shù) seed 值最好也是隨機(jī)出現(xiàn)的數(shù)字,例如利用加入時(shí)間做為變量的來源就是不錯(cuò)的方法,或者開發(fā)其它的硬體周邊界面可取得更好的隨機(jī)數(shù)。

使用范例

本例加入時(shí)間的因素,以執(zhí)行時(shí)的百萬分之一秒當(dāng)隨機(jī)數(shù)種子

<&#63;php
srand((double)microtime()*1000000);
$randval = rand();
echo $randval;
&#63;> 

參考: rand() getrandmax() mt_srand() mt_rand() mt_getrandmax()

Tan
正切計(jì)算。
語法: float tan(float arg);
返回值: 浮點(diǎn)數(shù)
函數(shù)種類: 數(shù)學(xué)運(yùn)算
內(nèi)容說明: 本函數(shù)計(jì)算參數(shù) arg 的正切值 (tangent)。
參考: Sin() Cos()

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www.bkjia.comtruehttp://www.bkjia.com/PHPjc/1117049.htmlTechArticlePHP數(shù)學(xué)運(yùn)算函數(shù)大匯總(經(jīng)典值得收藏),php值得收藏 本文匯總分析了PHP數(shù)學(xué)運(yùn)算函數(shù)。分享給大家供大家參考,具體如下: 一、常用函數(shù)說...
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