42 lines
859 B
Go
42 lines
859 B
Go
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package geo
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import "math"
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func EuclideanDistance(x1, y1, x2, y2 float64) float64 {
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if x1 == x2 {
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return math.Abs(y1 - y2)
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} else if y1 == y2 {
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return math.Abs(x1 - x2)
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} else {
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return math.Sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2))
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}
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}
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// compare a and b and consider them equal if
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// difference is less than precision e (e.g. e=0.001)
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func PrecisionCompare(a, b, e float64) int {
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if math.Abs(a-b) < e {
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return 0
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}
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if a < b {
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return -1
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}
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return 1
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}
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// TruncateDecimals truncates floats to keep up to 3 digits after decimal, to avoid issues with floats on different machines.
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// Since we're not launching rockets, 3 decimals is enough precision for what we're doing
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func TruncateDecimals(v float64) float64 {
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return float64(int(v*1000)) / 1000
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}
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func Sign(i float64) int {
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if i < 0 {
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return -1
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}
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if i > 0 {
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return 1
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}
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return 0
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}
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