Make x variable explicit in closure

jsbean · jsbean · commit 40d074807f83 · 2016-11-08T20:56:17.000-05:00
diff --git a/Linear Regression/LinearRegression.playground/Contents.swift b/Linear Regression/LinearRegression.playground/Contents.swift
@@ -42,7 +42,7 @@ func linearRegression(_ xs: [Double], _ ys: [Double]) -> ((Double) -> Double) {
     let sum2 = average(multiply(xs, xs)) - pow(average(xs), 2)
     let slope = sum1 / sum2
     let intercept = average(ys) - slope * average(xs)
-    return { intercept + slope * $0 }
+    return { x in intercept + slope * x }
 }
 
 let result = linearRegression(carAge, carPrice)(4)

Original file line number	Diff line number	Diff line change
`@@ -42,7 +42,7 @@ func linearRegression(_ xs: [Double], _ ys: [Double]) -> ((Double) -> Double) {`
`42`	`42`	`let sum2 = average(multiply(xs, xs)) - pow(average(xs), 2)`
`43`	`43`	`let slope = sum1 / sum2`
`44`	`44`	`let intercept = average(ys) - slope * average(xs)`
`45`		`- return { intercept + slope * $0 }`
	`45`	`+ return { x in intercept + slope * x }`
`46`	`46`	`}`
`47`	`47`
`48`	`48`	`let result = linearRegression(carAge, carPrice)(4)`