Cholesky decomposition: Difference between revisions

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 =={{header|Nim}}==
 {{trans|C}}
-<lang nim>import math, strutils
+<lang nim>import math, strutils, strformat
+type Matrix[N: static int, T: SomeFloat] = array[N, array[N, T]]
-proc cholesky[T](a: T): T =
-  for i in 0 .. < a[0].len:
+proc cholesky[Matrix](a: Matrix): Matrix =
+  for i in 0 ..< a[0].len:
     for j in 0 .. i:
       var s = 0.0
-      for k in 0 .. < j:
+      for k in 0 ..< j:
         s += result[i][k] * result[j][k]
       result[i][j] = if i == j: sqrt(a[i][i]-s)
-        else: (1.0 / result[j][j] * (a[i][j] - s))
+                     else: 1.0 / result[j][j] * (a[i][j] - s)
-proc `$`(a): string =
+proc `$`(a: Matrix): string =
   result = ""
   for b in a:
+    var line = ""
     for c in b:
+      line.addSep(" ", 0)
-      result.add c.formatFloat(ffDecimal, 5) & " "
-    result.add "\n"
+      line.add fmt"{c:8.5f}"
+    result.add line & '\n'
 let m1 = [[25.0, 15.0, -5.0],
@@ Line 2,238: / Line 2,242: @@
           [42.0, 62.0, 134.0, 106.0]]
 echo cholesky(m2)</lang>
-Output:
-<pre>5.00000 0.00000 0.00000
-.00000 3.00000 0.00000
--1.00000 1.00000 3.00000
+{{out}}
-.24264 0.00000 0.00000 0.00000
-.18545 6.56591 0.00000 0.00000
+<pre> 5.00000  0.00000  0.00000
-.72792 3.04604 1.64974 0.00000
+.00000  3.00000  0.00000
+-1.00000  1.00000  3.00000
-.89949 1.62455 1.84971 1.39262</pre>
+.24264  0.00000  0.00000  0.00000
+.18545  6.56591  0.00000  0.00000
+.72792  3.04604  1.64974  0.00000
+.89949  1.62455  1.84971  1.39262</pre>
 =={{header|Objeck}}==