Data commit

Task/Nth-root/Bracmat/nth-root.bracmat

@@ -0,0 +1,29 @@
+( ( root
+  =   n a d x0 x1 d2 rnd 10-d
+    .   ( rnd       { For 'rounding' rational numbers = keep number of digits within bounds. }
+        =   N r
+          .   !arg:(?N.?r)
+            & div$(!N*!r+1/2.1)*!r^-1
+        )
+      & !arg:(?n,?a,?d)
+      & !a*!n^-1:?x0
+      & 10^(-1*!d):?10-d
+      &   whl
+        ' (   ( rnd$(((!n+-1)*!x0+!a*!x0^(1+-1*!n))*!n^-1.10^!d)
+              . !x0
+              )
+            : (?x0.?x1)
+          & (!x0+-1*!x1)^2:~<!10-d   { Exit loop when required precision is reached. }
+          )
+      & flt$(!x0,!d)      { Convert rational number to floating point representation. }
+  )
+& ( show
+  =   N A precision
+    .   !arg:(?N,?A,?precision)
+      & out$(str$(!A "^(" !N^-1 ")=" root$(!N,!A,!precision)))
+  )
+& show$(10,1024,20)
+& show$(3,27,20)
+& show$(2,2,100)
+& show$(125,5642,20)
+)