SunshinePHP Developer Conference 2015

Mathematical Functions

  • Introducere
  • Instalarea / configurarea
  • Constante predefinite
  • Funcții matematice
    • abs — Absolute value
    • acos — Arc cosine
    • acosh — Inverse hyperbolic cosine
    • asin — Arc sine
    • asinh — Inverse hyperbolic sine
    • atan2 — Arc tangent of two variables
    • atan — Arc tangent
    • atanh — Inverse hyperbolic tangent
    • base_convert — Convert a number between arbitrary bases
    • bindec — Binary to decimal
    • ceil — Round fractions up
    • cos — Cosine
    • cosh — Hyperbolic cosine
    • decbin — Decimal to binary
    • dechex — Decimal to hexadecimal
    • decoct — Decimal to octal
    • deg2rad — Converts the number in degrees to the radian equivalent
    • exp — Calculates the exponent of e
    • expm1 — Returns exp(number) - 1, computed in a way that is accurate even when the value of number is close to zero
    • floor — Round fractions down
    • fmod — Returns the floating point remainder (modulo) of the division of the arguments
    • getrandmax — Show largest possible random value
    • hexdec — Hexadecimal to decimal
    • hypot — Calculate the length of the hypotenuse of a right-angle triangle
    • is_finite — Finds whether a value is a legal finite number
    • is_infinite — Finds whether a value is infinite
    • is_nan — Finds whether a value is not a number
    • lcg_value — Combined linear congruential generator
    • log10 — Base-10 logarithm
    • log1p — Returns log(1 + number), computed in a way that is accurate even when the value of number is close to zero
    • log — Natural logarithm
    • max — Find highest value
    • min — Find lowest value
    • mt_getrandmax — Show largest possible random value
    • mt_rand — Generate a better random value
    • mt_srand — Seed the better random number generator
    • octdec — Octal to decimal
    • pi — Get value of pi
    • pow — Exponential expression
    • rad2deg — Converts the radian number to the equivalent number in degrees
    • rand — Generate a random integer
    • round — Rounds a float
    • sin — Sine
    • sinh — Hyperbolic sine
    • sqrt — Square root
    • srand — Seed the random number generator
    • tan — Tangent
    • tanh — Hyperbolic tangent
add a note add a note

User Contributed Notes 1 note

up
-20
Hayley Watson
1 year ago
Provides a function to rescale numbers so that the range [a,b] fits into the range [c,d].

<?php
function rescale($ab, $cd)
{
    list(
$a, $b) = $ab;
    list(
$c, $d) = $cd;
    if(
$a == $b)
    {
       
trigger_error("Invalid scale", E_USER_WARNING);
        return
false;
    }
   
$o = ($b * $c - $a * $d) / ($b - $a);
   
$s = ($d - $c) / ($b - $a);
    return function(
$x)use($o, $s)
    {
        return
$s * $x + $o;
    };
}

$fahr2celsius = rescale([32, 212], [0, 100]);
echo 
$fahr2celsius(98.6); // 37°C

?>
To Top