The unit circle

Sine and cosine read off a rotating radius. Drag the angle, or let it run.

examples/showcase-unit-circle.axis

config {
    showGrid: true
    xAxisStep: 1
    yAxisStep: 1
    pointsOfInterest: true
}

"The unit circle"

ang = 0.9 @ slider: 0..2pi step 0.005, playing

folder "The circle" {
    (cos(t), sin(t)) @ color: BLACK, lineWidth: 2, lineOpacity: 0.5, domain: 0..tau
    P = (cos(ang), sin(ang)) @ color: PURPLE, pointSize: 18
    "The radius out to P."
    R = [(0, 0), P] @ color: PURPLE, lines, points: false, lineWidth: 3
}

folder "Reading off the components" {
    "cos is the horizontal leg, sin the vertical one."
    A = [(0, 0), (cos(ang), 0)] @ color: RED, lines, points: false, lineWidth: 4
    B = [(cos(ang), 0), P] @ color: BLUE, lines, points: false, lineWidth: 4
    (cos(ang), 0) @{
        color: RED
        pointSize: 14
        label: "cos"
        showLabel
        labelOrientation: below
    }
    (0, sin(ang)) @{
        color: BLUE
        pointSize: 14
        label: "sin"
        showLabel
        labelOrientation: left
    }
}

folder "Unrolled onto the wave" {
    "The same angle, plotted along the x-axis to the right of the circle."
    y = sin(x - 3) {3 < x < 9.3} @ color: BLUE, lineWidth: 3
    (ang + 3, sin(ang)) @ color: BLUE, pointSize: 16
    T = [P, (ang + 3, sin(ang))] @{
        color: BLUE
        lines
        points: false
        lineStyle: DOTTED
        lineOpacity: 0.6
    }
}

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