Constrained random points on a circle: Difference between revisions

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=={{header|Swift}}==

{{trans|Rust}}

<lang swift>let nPoints = 100

func generatePoint() -> (Int, Int) {

while true {

let x = Int.random(in: -15...16)

let y = Int.random(in: -15...16)

let r2 = x * x + y * y

if r2 >= 100 && r2 <= 225 {

return (x, y)

}

}

}

func filteringMethod() {

var rows = [[String]](repeating: Array(repeating: " ", count: 62), count: 31)

for _ in 0..<nPoints {

let (x, y) = generatePoint()

rows[y + 15][x + 15 * 2] = "*"

}

for row in rows {

print(row.joined())

}

}

func precalculatingMethod() {

var possiblePoints = [(Int, Int)]()

for y in -15...15 {

for x in -15...15 {

let r2 = x * x + y * y

if r2 >= 100 && r2 <= 225 {

possiblePoints.append((x, y))

}

}

}

possiblePoints.shuffle()

var rows = [[String]](repeating: Array(repeating: " ", count: 62), count: 31)

for (x, y) in possiblePoints {

rows[y + 15][x + 15 * 2] = "*"

}

for row in rows {

print(row.joined())

}

}

print("Filtering method:")

filteringMethod()

print("Precalculating method:")

precalculatingMethod()</lang>

{{out}}

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