Mathematical functions in PHP

Falcon · #1 (**permalink**) 04-15-2008, 12:37 AM

Hi Buddies,

Shall we discuss about mathematical functions. i want to know more about that for implementing in My site

Thanks
Falcon

Jeyaseelansarc · #2 (**permalink**) 04-15-2008, 12:52 AM

hi,
actually These math functions will only handle values within the range of the integer and float types on your computer.

The math functions are part of the PHP core. There is no installation needed to use these functions.

sureshbabu · #3 (**permalink**) 04-15-2008, 07:21 AM

abs
It returns absolute value
Description
number abs ( mixed $number )
Examples

<?php
$abs = abs(-4.2); // $abs = 4.2; (double/float)
$abs2 = abs(5); // $abs2 = 5; (integer)
$abs3 = abs(-5); // $abs3 = 5; (integer)
?>

Jeyaseelansarc · #4 (**permalink**) 04-16-2008, 02:15 AM

ceil() returns the next highest integer value by rounding up value if necessary. The return value of ceil() is still of type float as the value range of float is usually bigger than that of integer.

Example:

PHP Code:

  <?php

echo ceil(4.3);    // 5

echo ceil(9.999);  // 10

?>

Jeyaseelansarc · #5 (**permalink**) 04-16-2008, 02:16 AM

floor() returns the next lowest integer value by rounding down value if necessary. The return value of floor() is still of type float because the value range of float is usually bigger than that of integer.

example:

PHP Code:

  <?php

echo floor(4.3);   // 4

echo floor(9.999); // 9

?>

Jeyaseelansarc · #6 (**permalink**) 04-16-2008, 02:18 AM

round() returns the rounded value of val to specified precision (number of digits after the decimal point). precision can also be negative or zero (default).

Example:

PHP Code:

  <?php

echo round(3.4);         // 3

echo round(3.5);         // 4

echo round(3.6);         // 4

echo round(3.6, 0);      // 4

echo round(1.95583, 2);  // 1.96

echo round(1241757, -3); // 1242000

echo round(5.045, 2);    // 5.05

echo round(5.055, 2);    // 5.06

?>

senraj · #7 (**permalink**) 04-16-2008, 02:41 AM

Hi,

max() returns the numerically highest of the parameter values.If the first and only parameter is an array, max() returns the highest value in that array. If the first parameter is an integer, string or float, you need at least two parameters and max() returns the biggest of these values. You can compare an unlimited number of values.

senraj · #8 (**permalink**) 04-16-2008, 02:43 AM

Hi,

max() function example:

PHP Code:

  echo max(1, 3, 5, 6, 7); 

echo "</br>";

echo max(array(2, 4, 5));

 
output :

7

5

sureshbabu · #9 (**permalink**) 04-16-2008, 07:47 AM

cos()
The acos() function returns the arccosine of a number as a numeric value value between 0 and PI radians.

Syntax
acos(x)

Example
In this example we will get the arccosine of different numbers:

<?php
echo(acos(0.64) . " ");
echo(acos(0) . " ");
echo(acos(-1) . " ");
echo(acos(1) . " ");
echo(acos(2))
?>

sureshbabu · #10 (**permalink**) 04-16-2008, 07:48 AM

rad2deg()
The rad2deg() function converts a radian number to its degree.

Syntax
rad2deg(radian_number)
Example
<?php
$rad = M_PI;
$deg = rad2deg($rad);
echo "$rad radians is equal to $deg degrees";
?>

Jeyaseelansarc · #11 (**permalink**) 04-16-2008, 10:43 PM

exp() calculates the exponent of e (the Neperian or Natural logarithm base)

example:

PHP Code:

  <?php

echo exp(12) . "\n";

echo exp(5.7);

?>

The above example will output:

Code:

1.6275E+005
298.87

Jeyaseelansarc · #12 (**permalink**) 04-16-2008, 10:44 PM

pow() returns base raised to the power of exp. If possible, this function will return an integer.

If the power cannot be computed, a warning will be issued, and pow() will return FALSE. Since PHP 4.2.0 pow() doesn't issue any warning.

And PHP cannot handle negative bases

Example:

PHP Code:

  <?php

 
var_dump(pow(2, 8)); // int(256)

echo pow(-1, 20); // 1

echo pow(0, 0); // 1

 
echo pow(-1, 5.5); // error

 
?>

Jeyaseelansarc · #13 (**permalink**) 04-16-2008, 10:46 PM

sqrt() returns the square root of arg.

example:

PHP Code:

  <?php

// Precision depends on your precision directive

echo sqrt(9); // 3

echo sqrt(10); // 3.16227766 ...

?>

Falcon · #14 (**permalink**) 04-17-2008, 02:48 AM

Hi

is_finite()
The is_finite() function returns true if the specified value is a finite number, otherwise it returns nothing.

PHP Code:

  <?php

echo is_finite(2) . "<br />";

echo is_finite(log(0)) . "<br />";

echo is_finite(2000);

?>

Regards
Falcon

Falcon · #15 (**permalink**) 04-17-2008, 02:50 AM

Hi

acos()
The acos() function returns the arccosine of a number as a numeric value value between 0 and PI radians

PHP Code:

  <?php

echo(acos(0.64) . "<br />");

echo(acos(0) . "<br />");

echo(acos(-1) . "<br />");

echo(acos(1) . "<br />");

echo(acos(2))

?>

Regards
Falcon

Falcon · #16 (**permalink**) 04-17-2008, 02:54 AM

Hi

cos()
The cos() returns the cosine of a number.

PHP Code:

  <?php
echo(cos(3) . "<br />");
echo(cos(-3) . "<br />");
echo(cos(0) . "<br />");
echo(cos(M_PI) . "<br />");
echo(cos(2*M_PI))
?>

OutPut will be

Code:

-0.9899924966004454
-0.9899924966004454
1
-1
1

Regards
Falcon

Falcon · #17 (**permalink**) 04-17-2008, 03:00 AM

hi

cosh()
The cosh() function returns the hyperbolic cosine of a number (equivalent to (exp(x) + exp(-x)) / 2).

PHP Code:

  <?php

echo(cosh(3) . "<br />");

echo(cosh(-3) . "<br />");

echo(cosh(0) . "<br />");

echo(cosh(M_PI) . "<br />");

echo(cosh(2*M_PI))

?>

OutPut wiil be

Code:

10.0676619958
10.0676619958
1
11.5919532755
267.746761484

Regards
Falcon

saravanan · #18 (**permalink**) 04-17-2008, 07:00 AM

<?php
echo(rand() . " ");17757
echo(rand() . " ");3794
echo(rand(10,100)) ;97 it generate rand number between 1-100

?>

saravanan · #19 (**permalink**) 04-17-2008, 07:04 AM

<?php
echo is_nan(200) . " ";
echo is_nan(acos(1.01));
?>

The is_nan() function returns true if the specified value is "not a number", otherwise it returns nothing.
answer for above code
1.nothing
2.true ,its means it not a number

saravanan · #20 (**permalink**) 04-17-2008, 07:07 AM

<?php
echo decbin("3") . " ";
echo decbin("1") . " ";
echo decbin("1587") . " ";
echo decbin("7");
?>

this function to convert the decimal number into binary number
Answer for above code
11
1
11000110011
111