Data update

Task/Nth-root/QuickBASIC/nth-root.basic

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+' Nth root
+DECLARE FUNCTION NthRoot# (N%, X#, Precision#)
+X# = 144
+PRINT "Finding the nth root of"; X#; "to 6 decimal places"
+PRINT "  x      n        root    x ^ (1 / n)"
+PRINT "--------------------------------------"
+FOR I% = 1 TO 8
+  PRINT USING "###   "; X#;
+  PRINT USING "####    "; I%;
+  PRINT USING "###.######"; NthRoot#(I%, X#, .0000001);
+  PRINT USING "    ###.######"; X# ^ (1 / I%)
+NEXT I%
+END
+
+FUNCTION NthRoot# (N%, X#, Precision#)
+  ' Returns the Nth root of value X to stated Precision
+  X0# = X#
+  X1# = X# / N% ' initial guess
+  DO WHILE ABS(X1# - X0#) > Precision#
+    X0# = X1#
+    X1# = ((N% - 1) * X1# + X# / X1# ^ (N% - 1)) / N%
+  LOOP
+  NthRoot# = X1#
+END FUNCTION