Math Functions
In addition to the math operators such as +, _ and *, ActionScript3 has functions to find square root; trigonometric functions such as sin and cosine, and many others. You can see a list of the functions by typing the following: trace(Math. As soon as you type the dot you will see a drop down list with all of the functions:
Finish typing the line as:
trace(Math.sqrt(16);
When you run the movie, this will display 4 in the output window. Functions receive values and return a result. In the example above Math.sqrt receives 16 and returns 4. That value is then displayed by the trace function. Try a few other functions that you are familiar with.
A few other functions that are useful are shown below. Use these with trace to test:
| Function | Purpose | Example | Return Value |
|---|---|---|---|
| abs | absolute | Math.abs(-5) | 5 |
| ceil | ceiling: rounds up by moving right on timeline to a whole number | Math.ceil(3.8) | 4 |
| Math.ceil(-3.8) | -3 | ||
| floor | floor: rounds down by moving left on timeline to a whole number | Math.floor(3.8) | 3 |
| Math.floor(-3.8) | -4 | ||
| round | rounds to the nearest integer | Math.round(3.8) | 4 |
| Math.round(3.2) | 3 | ||
| max | returns the largest of two integers | Math.max(8,3) | 8 |
| min | returns the smallest of two integers | Math.min(8,3) | 3 |
| PI | returns pi: | Math.PI | 3.141592653589793 |
| random | returns a random value >=0 and <1 | Math.random() | 0.9147554710507393 |
| pow | raises a number to a power | Math.pow(2,3) | 8 (2 to the 3rd power or 2*2*2) |
There are also a number of trigonometry functions: acos (arc cosine), asin (arc sine), atan (arc tangent), atan2 (angle from x axis to a point), cos (cosine), sin (sine), tan (tangent).
INDEX, Math functions, Arrow follows cursor, A Yo-yo with sin function, Eyes follow the cursor
Next lesson: Random Numbers: Math.Random()
