pxt-calliope/docs/reference/led/plot.md
2016-04-13 08:27:45 -07:00

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# Plot
Turn on a LED light on the [LED screen](/device/screen). Specify which LED using x, y coordinates. Use [unplot](/reference/led/unplot) to turn a LED off.
```sig
led.plot(0,0);
```
### Parameters
* x - [Number](/reference/types/number); the *x coordinate* or horizontal position (0, 1, 2, 3, 4)
* y - [Number](/reference/types/number); the *y coordinate* or vertical position (0, 1, 2, 3, 4)
If a parameter is [out of bounds](/reference/out-of-bounds) (a value other than 0-4), then this function will do nothing.
### x, y coordinates?
The LED screen is made up of 25 LEDs arranged in a 5x5 grid. To figure out the ``x``, ``y`` coordinates, see [LED screen](/device/screen).
This code turns on the centre LED:
```blocks
led.plot(2, 2)
```
### Get the LED on/off state
Use the [point](/reference/led/point) function to find out if a LED is on or off.
### Example: a square
The following example uses a [for loop](/reference/loops/for) and the `plot` function to turn on the LED lights along the edge of the screen, making a square:
```blocks
for (let i = 0; i < 5; i++) {
led.plot(0, i)
led.plot(4, i)
led.plot(i, 0)
led.plot(i, 4)
basic.pause(500)
}
```
### Lessons
[blink](/lessons/blink), [beautiful image](/lessons/beautiful-image), [strobe light](/lessons/strobe-light)
### See also
[unplot](/reference/led/unplot), [point](/reference/led/point), [LED screen](/device/screen)