Polynomial regression: Difference between revisions

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@@ Line 1,647: / Line 1,647: @@
 =={{header|Sidef}}==
 {{trans|Ruby}}
-<lang ruby>var Matrix = require('Math::Matrix')
+<lang ruby>func regress(x, y, degree) {
+    var A = Matrix.build(x.len, degree+1, {|i,j|
+        x[i]**j
+    })
+    var B = Matrix.column_vector(y...)
-func regress(x, y, degree) {
+    ((A.transpose * A)**(-1) * A.transpose * B).transpose[0]
-    var x_data = x.map {|xi| (0..degree).map {|pow| xi**pow } }
+}
-    var mx = Matrix.new(x_data...)
-    var my = Matrix.new(y.map{[_]}...)
+func poly(x) {
-    mx.transpose.multiply(mx).invert.multiply(mx.transpose).multiply(my).transpose
+*x**2 + 2*x + 1
 }
-var betas = regress(
+var coeff = regress(
+.of { _ },
-    [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
+.of { poly(_) },
-    [1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321],
 )
-betas.print</lang>
+say coeff</lang>
 {{out}}
 <pre>
+[1, 2, 3]
-.00000    2.00000    3.00000
 </pre>