Data commit

Task/Nth-root/Action-/nth-root.action

@@ -0,0 +1,46 @@
+INCLUDE "H6:REALMATH.ACT"
+
+PROC NthRoot(REAL POINTER a,n REAL POINTER res)
+  REAL n1,eps,one,tmp1,tmp2,tmp3
+
+  ValR("0.0001",eps)
+  IntToReal(1,one)
+  RealSub(n,one,n1)
+
+  Sqrt(a,res)            ;res=sqrt(a)
+  DO
+    Power(res,n,tmp1)    ;tmp=res^n
+    RealSub(a,tmp1,tmp2) ;tmp2=a-res^n
+    RealAbs(tmp2,tmp1)       ;tmp1=abs(a-res^n)
+    IF RealGreaterOrEqual(eps,tmp1) THEN
+      RETURN
+    FI
+
+    Power(res,n1,tmp1)      ;tmp1=res^(n-1)
+    RealDiv(a,tmp1,tmp2)    ;tmp2=a/(res^(n-1))
+    RealMult(n1,res,tmp1)   ;tmp1=(n-1)*res
+    RealAdd(tmp1,tmp2,tmp3) ;tmp3=((n-1)*res + a/(res^(n-1)))
+    RealDiv(tmp3,n,res)     ;res=((n-1)*res + a/(res^(n-1)))/n
+  OD
+RETURN
+
+PROC Test(CHAR ARRAY sa,sn)
+  REAL a,n,res
+
+  ValR(sa,a)
+  ValR(sn,n)
+  PrintR(n) Print(" root of ")
+  PrintR(a) Print(" is ")
+  NthRoot(a,n,res)
+  PrintRE(res)
+RETURN
+
+PROC Main()
+  Put(125) PutE() ;clear screen
+  MathInit()
+  Test("2","2")
+  Test("81","4")
+  Test("1024","10")
+  Test("7","0.5")
+  Test("12.34","56.78")
+RETURN