Php-mysql Course

PHP has both integer and float (decimal) number types. These two types can be classified under the generic title numbers.
Valid numbers can be anything like:   8,   258,   -37,   89.25,   -3.5785,   5.5e2
- Number-type values are never quoted. The numbers added within quotes are strings with numeric values.
PHP supports a maximum integer of around two billion on most platforms (UNIX and Windows). With numbers larger than that, PHP will automatically use a floating-point type.

1. Numbers and Operator

The mathematical operators are specific symbols that performs mathematical calculations.
Operators act on the variables and numbers presented in PHP instructions.

The standard mathematical (Arithmetic) operators


Assignment Operators


The mathematical calculations in PHP, as in arithmetic, are taken into account the operators precedence (the order in which complex calculations are made). If you want to force the execution order, you must group clauses in parentheses. Check the fallowing example:
<?php
$x = 8 + 3 * 5 -2;
echo $x;                  // 21 (first 3*5 [15], then adds 8 and substract 2 )

$x = (8+3) * (5-2);
echo '<br />'. $x;        // 33  (first 8+3  [11], then  5-2 [3], then makes the multiplication  11*3 [33] )
?>

2. PHP mathematical functions

Along with the arithmetic operators you can use PHP mathematical functions for more complex operations.
Here are some examples of functions:

Daily Test with Code Example

HTML
CSS
JavaScript
PHP-MySQL
Which type of <input> creates input fields that should contain a numeric value?
type="text" type="number" type="date"
<input type="number" name="points" min="5" max="80" />
Which CSS property allows to change the transparency of an element?
font-style opacity color
#id {
  filter:alpha(opacity=40);    /* for IE */
  opacity:0.4;
}
Click on the function that formats a number to specified number of characters.
toPrecision() exp() toFixed()
var num = 12.34567;
alert( num.toPrecision(3) );       // 12.3
Which function randomizes the order of the elements into an array?
natsort() shuffle() sort()
$lang =[10=>"PHP", 20=>"JavaScript", "site"=>"coursesweb.net");
shuffle($lang);
var_export($lang);     // array (0=>"coursesweb.net", 1=>"PHP", 2=>"JavaScript")
Numbers and mathematical 0perators

Last accessed pages

  1. Get the value of the selected /checked checkboxes in a form (43247)
  2. $_GET, $_POST and $_REQUEST Variables (30421)
  3. Making DIV Contents Scroll Horizontally, with multiple Div`s inside (56581)
  4. Add text between two DIV tags (1982)
  5. Brush and Eraser (2551)

Popular pages this month

  1. Courses Web: PHP-MySQL JavaScript Node.js Ajax HTML CSS (233)
  2. PHP-MySQL free course, online tutorials PHP MySQL code (158)
  3. Read Excel file data in PHP - PhpExcelReader (147)
  4. querySelector and querySelectorAll (105)
  5. Wake Up! (101)