# Methods

#### # static add(v1, v2, target)

##### Parameters:

Name | Type | Description
--- | --- | ---
`v1` | PVector | a PVector to add
`v2` | PVector | a PVector to add
`target` | PVector | the vector to receive the result

#### # static cross(v1, v2) → {Number}

Calculates the cross product of two vectors.

##### Parameters:

Name | Type | Description
--- | --- | ---
`v1` | PVector | the first PVector
`v2` | PVector | the second PVector

Returns:
the cross product
Type: Number

#### # static dist(v1, v2) → {Number}

Calculates the Euclidean distance between two points (considering a point as a vector object).

##### Parameters:

Name | Type | Description
--- | --- | ---
`v1` | PVector | the first PVector
`v2` | PVector | the second PVector

Returns:
the distance
Type: Number

#### # static div(v, n, target)

Divides a vector by a scalar and returns a new vector.

##### Parameters:

Name | Type | Description
--- | --- | ---
`v` | PVector | the vector to divide
`n` | Number |
`target` | PVector | if undefined a new vector will be created

#### # static dot(v1, v2) → {Number}

Calculates the dot product of two vectors.

##### Parameters:

Name | Type | Description
--- | --- | ---
`v1` | PVector | the first PVector
`v2` | PVector | the second PVector

Returns:
the dot product
Type: Number

#### # static fromAngle(angle, lengthopt) → {PVector}

Make a new 2D vector from an angle

##### Parameters:

Name | Type | Attributes | Description
--- | --- | --- | ---
`angle` | Number |  | the desired angle, in radians
`length` | Number | <optional> | the length of the new vector (defaults to 1)

Returns:
the new PVector object
Type: PVector

##### Example

    function draw() {
      background(200);

      // Create a variable, proportional to the mouseX,
      // varying from 0-360, to represent an angle in degrees.
      angleMode(DEGREES);
      let myDegrees = map(mouseX, 0, width, 0, 360);

      // Display that variable in an onscreen text.
      // (Note the nfc() function to truncate additional decimal places,
      // and the "\xB0" character for the degree symbol.)
      let readout = 'angle = ' + nfc(myDegrees, 1) + '\xB0';
      noStroke();
      fill(0);
      text(readout, 5, 15);

      // Create a PVector using the fromAngle function,
      // and extract its x and y components.
      let v = PVector.fromAngle(radians(myDegrees), 30);
      let vx = v.x;
      let vy = v.y;

      push();
      translate(width / 2, height / 2);
      noFill();
      stroke(150);
      line(0, 0, 30, 0);
      stroke(0);
      line(0, 0, vx, vy);
      pop();
    }

#### # static fromAngles(theta, phi, lengthopt) → {PVector}

Make a new 3D vector from a pair of ISO spherical angles

##### Parameters:

Name | Type | Attributes | Description
--- | --- | --- | ---
`theta` | Number |  | the polar angle, in radians (zero is up)
`phi` | Number |  | the azimuthal angle, in radians (zero is out of the screen)
`length` | Number | <optional> | the length of the new vector (defaults to 1)

Returns:
the new PVector object
Type: PVector

##### Example

    * function setup() {
      createCanvas(100, 100, WEBGL);
      fill(255);
      noStroke();
    }
    function draw() {
      background(255);

      let t = millis() / 1000;

      // add three point lights
      pointLight(color('#f00'), PVector.fromAngles(t * 1.0, t * 1.3, 100));
      pointLight(color('#0f0'), PVector.fromAngles(t * 1.1, t * 1.2, 100));
      pointLight(color('#00f'), PVector.fromAngles(t * 1.2, t * 1.1, 100));

      sphere(35);
    }

#### # static lerp(v1, v2, amt) → {Number}

Linear interpolate a vector to another vector and return the result as a new vector.

##### Parameters:

Name | Type | Description
--- | --- | ---
`v1` | PVector |
`v2` | PVector |
`amt` | Number |

Returns:
the lerped value
Type: Number

#### # static mag(vecT) → {Number}

##### Parameters:

Name | Type | Description
--- | --- | ---
`vecT` | PVector | the vector to return the magnitude of

Returns:
the magnitude of vecT
Type: Number

#### # static mult(v, n, target)

Multiplies a vector by a scalar and returns a new vector.

##### Parameters:

Name | Type | Description
--- | --- | ---
`v` | PVector | the vector to multiply
`n` | Number |
`target` | PVector | if undefined a new vector will be created

#### # static random2D() → {PVector}

Make a new 2D unit vector from a random angle

Returns:
the new PVector object
Type: PVector

##### Example

    let v = PVector.random2D();
    // May make v's attributes something like:
    // [0.61554617, -0.51195765, 0.0] or
    // [-0.4695841, -0.14366731, 0.0] or
    // [0.6091097, -0.22805278, 0.0]
    print(v);

    function setup() {
      frameRate(1);
    }

    function draw() {
      background(240);

      let v0 = createVector(50, 50);
      let v1 = PVector.random2D();
      drawArrow(v0, v1.mult(50), 'black');
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # static random3D() → {PVector}

Make a new random 3D unit vector.

Returns:
the new PVector object
Type: PVector

##### Example

    let v = PVector.random3D();
    // May make v's attributes something like:
    // [0.61554617, -0.51195765, 0.599168] or
    // [-0.4695841, -0.14366731, -0.8711202] or
    // [0.6091097, -0.22805278, -0.7595902]
    print(v);

#### # static sub(v1, v2, target)

Subtracts one PVector from another and returns a new one. The second vector (v2) is subtracted from the first (v1), resulting in v1-v2.

##### Parameters:

Name | Type | Description
--- | --- | ---
`v1` | PVector | a PVector to subtract from
`v2` | PVector | a PVector to subtract
`target` | PVector | if undefined a new vector will be created

#### # inner add(x, yopt, zopt)

Adds x, y, and z components to a vector, adds one vector to another, or adds two independent vectors together. The version of the method that adds two vectors together is a static method and returns a PVector, the others acts directly on the vector. See the examples for more context.

##### Parameters:

Name | Type | Attributes | Description
--- | --- | --- | ---
`x` | Number |  | the x component of the vector to be added
`y` | Number | <optional> | the y component of the vector to be added
`z` | Number | <optional> | the z component of the vector to be added

##### Example

    let v = createVector(1, 2, 3);
    v.add(4, 5, 6);
    // v's components are set to [5, 7, 9]
    // Static method
    let v1 = createVector(1, 2, 3);
    let v2 = createVector(2, 3, 4);

    let v3 = PVector.add(v1, v2);
    // v3 has components [3, 5, 7]
    print(v3);

    // red vector + blue vector = purple vector
    function draw() {
      background(240);

      let v0 = createVector(0, 0);
      let v1 = createVector(mouseX, mouseY);
      drawArrow(v0, v1, 'red');

      let v2 = createVector(-30, 20);
      drawArrow(v1, v2, 'blue');

      let v3 = PVector.add(v1, v2);
      drawArrow(v0, v3, 'purple');
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner angleBetween(the) → {Number}

Calculates and returns the angle (in radians) between two vectors.

##### Parameters:

Name | Type | Description
--- | --- | ---
`the` | PVector | x, y, and z components of a PVector

Returns:
the angle between (in radians)
Type: Number

##### Example

    let v1 = createVector(1, 0, 0);
    let v2 = createVector(0, 1, 0);

    let angle = v1.angleBetween(v2);
    // angle is PI/2
    print(angle);

    function draw() {
      background(240);
      let v0 = createVector(50, 50);

      let v1 = createVector(50, 0);
      drawArrow(v0, v1, 'red');

      let v2 = createVector(mouseX - 50, mouseY - 50);
      drawArrow(v0, v2, 'blue');

      let angleBetween = v1.angleBetween(v2);
      noStroke();
      text(
        'angle between: ' +
          angleBetween.toFixed(2) +
          ' radians or ' +
          degrees(angleBetween).toFixed(2) +
          ' degrees',
        10,
        50,
        90,
        50
      );
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner array() → {Array.<Number>}

Return a representation of this vector as a float array. This is only for temporary use. If used in any other fashion, the contents should be copied by using the PVector.copy() method to copy into your own array.

Returns:
an Array with the 3 values
Type: Array.<Number>

##### Example

    * function setup() {
      let v = createVector(20, 30);
      print(v.array()); // Prints : Array [20, 30, 0]
    }

    let v = createVector(10.0, 20.0, 30.0);
    let f = v.array();
    print(f[0]); // Prints "10.0"
    print(f[1]); // Prints "20.0"
    print(f[2]); // Prints "30.0"

#### # inner copy() → {PVector}

Gets a copy of the vector, returns a PVector object.

Returns:
the copy of the PVector object
Type: PVector

##### Example

    let v1 = createVector(1, 2, 3);
    let v2 = v1.copy();
    print(v1.x === v2.x && v1.y === v2.y && v1.z === v2.z);
    // Prints "true"

#### # inner cross(v) → {PVector}

Calculates and returns a vector composed of the cross product between two vectors. Both the static and non static methods return a new PVector. See the examples for more context.

##### Parameters:

Name | Type | Description
--- | --- | ---
`v` | PVector | PVector to be crossed

Returns:
PVector composed of cross product
Type: PVector

##### Example

    let v1 = createVector(1, 2, 3);
    let v2 = createVector(1, 2, 3);

    v1.cross(v2); // v's components are [0, 0, 0]

    // Static method
    let v1 = createVector(1, 0, 0);
    let v2 = createVector(0, 1, 0);

    let crossProduct = PVector.cross(v1, v2);
    // crossProduct has components [0, 0, 1]
    print(crossProduct);

#### # inner dist(v) → {Number}

Calculates the Euclidean distance between two points (considering a point as a vector object).

##### Parameters:

Name | Type | Description
--- | --- | ---
`v` | PVector | the x, y, and z coordinates of a PVector

Returns:
the distance
Type: Number

##### Example

    let v1 = createVector(1, 0, 0);
    let v2 = createVector(0, 1, 0);

    let distance = v1.dist(v2); // distance is 1.4142...
    print(distance);

    // Static method
    let v1 = createVector(1, 0, 0);
    let v2 = createVector(0, 1, 0);

    let distance = PVector.dist(v1, v2);
    // distance is 1.4142...
    print(distance);

    function draw() {
      background(240);

      let v0 = createVector(0, 0);

      let v1 = createVector(70, 50);
      drawArrow(v0, v1, 'red');

      let v2 = createVector(mouseX, mouseY);
      drawArrow(v0, v2, 'blue');

      noStroke();
      text('distance between vectors: ' + v2.dist(v1).toFixed(2), 5, 50, 95, 50);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner div(n)

Divide the vector by a scalar. The static version of this method creates a new PVector while the non static version acts on the vector directly. See the examples for more context.

##### Parameters:

Name | Type | Description
--- | --- | ---
`n` | number | the number to divide the vector by

##### Example

    let v = createVector(6, 4, 2);
    v.div(2); //v's components are set to [3, 2, 1]

    // Static method
    let v1 = createVector(6, 4, 2);
    let v2 = PVector.div(v1, 2);
    // v2 has components [3, 2, 1]
    print(v2);

    function draw() {
      background(240);

      let v0 = createVector(0, 100);
      let v1 = createVector(50, -50);
      drawArrow(v0, v1, 'red');

      let num = map(mouseX, 0, width, 10, 0.5, true);
      let v2 = PVector.div(v1, num);
      drawArrow(v0, v2, 'blue');

      noStroke();
      text('divided by ' + num.toFixed(2), 10, 90);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner dot(x, yopt, zopt) → {Number}

Calculates the dot product of two vectors. The version of the method that computes the dot product of two independent vectors is a static method. See the examples for more context.

##### Parameters:

Name | Type | Attributes | Description
--- | --- | --- | ---
`x` | Number |  | x component of the vector
`y` | Number | <optional> | y component of the vector
`z` | Number | <optional> | z component of the vector

Returns:
the dot product
Type: Number

##### Example

    let v1 = createVector(1, 2, 3);
    let v2 = createVector(2, 3, 4);

    print(v1.dot(v2)); // Prints "20"

    //Static method
    let v1 = createVector(1, 2, 3);
    let v2 = createVector(3, 2, 1);
    print(PVector.dot(v1, v2)); // Prints "10"

#### # inner dot(value) → {Number}

##### Parameters:

Name | Type | Description
--- | --- | ---
`value` | PVector | value component of the vector or a PVector

Returns:
Type: Number

#### # inner equals(xopt, yopt, zopt) → {Boolean}

Equality check against a PVector

##### Parameters:

Name | Type | Attributes | Description
--- | --- | --- | ---
`x` | Number | <optional> | the x component of the vector
`y` | Number | <optional> | the y component of the vector
`z` | Number | <optional> | the z component of the vector

Returns:
whether the vectors are equals
Type: Boolean

##### Example

    * let v1 = createVector(5, 10, 20);
    let v2 = createVector(5, 10, 20);
    let v3 = createVector(13, 10, 19);

    print(v1.equals(v2.x, v2.y, v2.z)); // true
    print(v1.equals(v3.x, v3.y, v3.z)); // false

    let v1 = createVector(10.0, 20.0, 30.0);
    let v2 = createVector(10.0, 20.0, 30.0);
    let v3 = createVector(0.0, 0.0, 0.0);
    print(v1.equals(v2)); // true
    print(v1.equals(v3)); // false

#### # inner equals(value) → {Boolean}

##### Parameters:

Name | Type | Description
--- | --- | ---
`value` | PVector | Array | the vector to compare

Returns:
Type: Boolean

#### # inner heading() → {Number}

Calculate the angle of rotation for this vector (only 2D vectors)

Returns:
the angle of rotation
Type: Number

##### Example

    * function setup() {
      let v1 = createVector(30, 50);
      print(v1.heading()); // 1.0303768265243125

      v1 = createVector(40, 50);
      print(v1.heading()); // 0.8960553845713439

      v1 = createVector(30, 70);
      print(v1.heading()); // 1.1659045405098132
    }

    function draw() {
      background(240);

      let v0 = createVector(50, 50);
      let v1 = createVector(mouseX - 50, mouseY - 50);

      drawArrow(v0, v1, 'black');

      let myHeading = v1.heading();
      noStroke();
      text(
        'vector heading: ' +
          myHeading.toFixed(2) +
          ' radians or ' +
          degrees(myHeading).toFixed(2) +
          ' degrees',
        10,
        50,
        90,
        50
      );
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner lerp(x, y, z, amt)

Linear interpolate the vector to another vector

##### Parameters:

Name | Type | Description
--- | --- | ---
`x` | Number | the x component
`y` | Number | the y component
`z` | Number | the z component
`amt` | Number | the amount of interpolation; some value between 0.0 (old vector) and 1.0 (new vector). 0.9 is very near the new vector. 0.5 is halfway in between.

##### Example

    let v = createVector(1, 1, 0);

    v.lerp(3, 3, 0, 0.5); // v now has components [2,2,0]

    let v1 = createVector(0, 0, 0);
    let v2 = createVector(100, 100, 0);

    let v3 = PVector.lerp(v1, v2, 0.5);
    // v3 has components [50,50,0]
    print(v3);

    let step = 0.01;
    let amount = 0;

    function draw() {
      background(240);
      let v0 = createVector(0, 0);

      let v1 = createVector(mouseX, mouseY);
      drawArrow(v0, v1, 'red');

      let v2 = createVector(90, 90);
      drawArrow(v0, v2, 'blue');

      if (amount > 1 || amount < 0) {
        step *= -1;
      }
      amount += step;
      let v3 = PVector.lerp(v1, v2, amount);

      drawArrow(v0, v3, 'purple');
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner limit(max)

Limit the magnitude of this vector to the value used for the max parameter.

##### Parameters:

Name | Type | Description
--- | --- | ---
`max` | Number | the maximum magnitude for the vector

##### Example

    let v = createVector(10, 20, 2);
    // v has components [10.0, 20.0, 2.0]
    v.limit(5);
    // v's components are set to
    // [2.2271771, 4.4543543, 0.4454354]
    * * function draw() {
      background(240);

      let v0 = createVector(50, 50);
      let v1 = createVector(mouseX - 50, mouseY - 50);

      drawArrow(v0, v1, 'red');
      drawArrow(v0, v1.limit(35), 'blue');

      noFill();
      ellipse(50, 50, 35 * 2);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner mag() → {Number}

Calculates the magnitude (length) of the vector and returns the result as a float (this is simply the equation sqrt(x*x + y*y + z*z).)

Returns:
magnitude of the vector
Type: Number

##### Example

    function draw() {
      background(240);

      let v0 = createVector(0, 0);
      let v1 = createVector(mouseX, mouseY);
      drawArrow(v0, v1, 'black');

      noStroke();
      text('vector length: ' + v1.mag().toFixed(2), 10, 70, 90, 30);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }
    * * let v = createVector(20.0, 30.0, 40.0);
    let m = v.mag();
    print(m); // Prints "53.85164807134504"

#### # inner magSq() → {number}

Calculates the squared magnitude of the vector and returns the result as a float (this is simply the equation (x*x + y*y + z*z).) Faster if the real length is not required in the case of comparing vectors, etc.

Returns:
squared magnitude of the vector
Type: number

##### Example

    // Static method
    let v1 = createVector(6, 4, 2);
    print(v1.magSq()); // Prints "56"

    function draw() {
      background(240);

      let v0 = createVector(0, 0);
      let v1 = createVector(mouseX, mouseY);
      drawArrow(v0, v1, 'black');

      noStroke();
      text('vector length squared: ' + v1.magSq().toFixed(2), 10, 45, 90, 55);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner mult(n)

Multiply the vector by a scalar. The static version of this method creates a new PVector while the non static version acts on the vector directly. See the examples for more context.

##### Parameters:

Name | Type | Description
--- | --- | ---
`n` | Number | the number to multiply with the vector

##### Example

    let v = createVector(1, 2, 3);
    v.mult(2);
    // v's components are set to [2, 4, 6]

    // Static method
    let v1 = createVector(1, 2, 3);
    let v2 = PVector.mult(v1, 2);
    // v2 has components [2, 4, 6]
    print(v2);

    function draw() {
      background(240);

      let v0 = createVector(50, 50);
      let v1 = createVector(25, -25);
      drawArrow(v0, v1, 'red');

      let num = map(mouseX, 0, width, -2, 2, true);
      let v2 = PVector.mult(v1, num);
      drawArrow(v0, v2, 'blue');

      noStroke();
      text('multiplied by ' + num.toFixed(2), 5, 90);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner normalize() → {PVector}

Normalize the vector to length 1 (make it a unit vector).

Returns:
normalized PVector
Type: PVector

##### Example

    let v = createVector(10, 20, 2);
    // v has components [10.0, 20.0, 2.0]
    v.normalize();
    // v's components are set to
    // [0.4454354, 0.8908708, 0.089087084]
    * * function draw() {
      background(240);

      let v0 = createVector(50, 50);
      let v1 = createVector(mouseX - 50, mouseY - 50);

      drawArrow(v0, v1, 'red');
      v1.normalize();
      drawArrow(v0, v1.mult(35), 'blue');

      noFill();
      ellipse(50, 50, 35 * 2);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner rotate(angle)

Rotate the vector by an angle (only 2D vectors), magnitude remains the same

##### Parameters:

Name | Type | Description
--- | --- | ---
`angle` | number | the angle of rotation

##### Example

    let v = createVector(10.0, 20.0);
    // v has components [10.0, 20.0, 0.0]
    v.rotate(HALF_PI);
    // v's components are set to [-20.0, 9.999999, 0.0]

    let angle = 0;
    function draw() {
      background(240);

      let v0 = createVector(50, 50);
      let v1 = createVector(50, 0);

      drawArrow(v0, v1.rotate(angle), 'black');
      angle += 0.01;
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner set(xopt, yopt, zopt)

Sets the x, y, and z component of the vector using two or three separate variables, the data from a PVector, or the values from a float array.

##### Parameters:

Name | Type | Attributes | Description
--- | --- | --- | ---
`x` | Number | <optional> | the x component of the vector
`y` | Number | <optional> | the y component of the vector
`z` | Number | <optional> | the z component of the vector

##### Example

    function setup() {
      let v = createVector(1, 2, 3);
      v.set(4, 5, 6); // Sets vector to [4, 5, 6]

      let v1 = createVector(0, 0, 0);
      let arr = [1, 2, 3];
      v1.set(arr); // Sets vector to [1, 2, 3]
    }

    let v0, v1;
    function setup() {
      createCanvas(100, 100);

      v0 = createVector(0, 0);
      v1 = createVector(50, 50);
    }

    function draw() {
      background(240);

      drawArrow(v0, v1, 'black');
      v1.set(v1.x + random(-1, 1), v1.y + random(-1, 1));

      noStroke();
      text('x: ' + round(v1.x) + ' y: ' + round(v1.y), 20, 90);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner setMag(len)

Set the magnitude of this vector to the value used for the len parameter.

##### Parameters:

Name | Type | Description
--- | --- | ---
`len` | number | the new length for this vector

##### Example

    let v = createVector(10, 20, 2);
    // v has components [10.0, 20.0, 2.0]
    v.setMag(10);
    // v's components are set to [6.0, 8.0, 0.0]

    function draw() {
      background(240);

      let v0 = createVector(0, 0);
      let v1 = createVector(50, 50);

      drawArrow(v0, v1, 'red');

      let length = map(mouseX, 0, width, 0, 141, true);
      v1.setMag(length);
      drawArrow(v0, v1, 'blue');

      noStroke();
      text('magnitude set to: ' + length.toFixed(2), 10, 70, 90, 30);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner sub(x, yopt, zopt)

Subtracts x, y, and z components from a vector, subtracts one vector from another, or subtracts two independent vectors. The version of the method that subtracts two vectors is a static method and returns a PVector, the other acts directly on the vector. See the examples for more context.

##### Parameters:

Name | Type | Attributes | Description
--- | --- | --- | ---
`x` | Number |  | the x component of the vector to subtract
`y` | Number | <optional> | the y component of the vector to subtract
`z` | Number | <optional> | the z component of the vector to subtract

##### Example

    let v = createVector(4, 5, 6);
    v.sub(1, 1, 1);
    // v's components are set to [3, 4, 5]

    // Static method
    let v1 = createVector(2, 3, 4);
    let v2 = createVector(1, 2, 3);

    let v3 = PVector.sub(v1, v2);
    // v3 has components [1, 1, 1]
    print(v3);

    // red vector - blue vector = purple vector
    function draw() {
      background(240);

      let v0 = createVector(0, 0);
      let v1 = createVector(70, 50);
      drawArrow(v0, v1, 'red');

      let v2 = createVector(mouseX, mouseY);
      drawArrow(v0, v2, 'blue');

      let v3 = PVector.sub(v1, v2);
      drawArrow(v2, v3, 'purple');
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }

#### # inner toString() → {String}

Returns a string representation of a vector v by calling String(v) or v.toString(). This method is useful for logging vectors in the console.

Returns:
Type: String

##### Example

    function setup() {
      let v = createVector(20, 30);
      print(String(v)); // prints "PVector Object : [20, 30, 0]"
    }

    function draw() {
      background(240);

      let v0 = createVector(0, 0);
      let v1 = createVector(mouseX, mouseY);
      drawArrow(v0, v1, 'black');

      noStroke();
      text(v1.toString(), 10, 25, 90, 75);
    }

    // draw an arrow for a vector at a given base position
    function drawArrow(base, vec, myColor) {
      push();
      stroke(myColor);
      strokeWeight(3);
      fill(myColor);
      translate(base.x, base.y);
      line(0, 0, vec.x, vec.y);
      rotate(vec.heading());
      let arrowSize = 7;
      translate(vec.mag() - arrowSize, 0);
      triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0);
      pop();
    }