Reduced row echelon form: Difference between revisions

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@@ Line 1,430: / Line 1,430: @@
 replace n e l = a ++ e : b
   where (a, _ : b) = splitAt n l</lang>
+=={{header|Icon}} and {{header|Unicon}}==
+Works in both languages:
+<lang unicon>procedure main(A)
+    tM := [[  1,  2, -1, -4],
+           [  2,  3, -1,-11],
+           [ -2,  0, -3, 22]]
+    showMat(rref(tM))
+end
+procedure rref(M)
+    lead := 1
+    rCount := *\M | stop("no Matrix?")
+    cCount := *(M[1]) | 0
+    every r := !rCount do {
+        i := r
+        while M[i,lead] = 0 do {
+            if (i+:=1) > rCount then {
+                i := r
+                if cCount < (lead +:= 1) then stop("can't reduce")
+                }
+            }
+        M[i] :=: M[r]
+        if 0 ~= (m0 := M[r,lead]) then every !M[r] /:= real(m0)
+        every r ~= (i := !rCount) do {
+            every !(mr := copy(M[r])) *:= M[i,lead]
+            every M[i,j := !cCount] -:= mr[j]
+            }
+        lead +:= 1
+        }
+    return M
+end
+procedure showMat(M)
+    every r := !M do every writes(right(!r,5)||" " | "\n")
+end</lang>
+Output:
+<pre>
+->rref
+.0   0.0   0.0  -8.0
+.0   1.0   0.0   1.0
+.0   0.0   1.0  -2.0
+->
+</pre>
 =={{header|J}}==