new file mode 100644
--- /dev/null
+++ b/scripts/plot/stairs.m
@@ -0,0 +1,78 @@
+function [xs, ys] = stairs (x, y)
+
+# usage: [xs, ys] = bar (x, y)
+#
+# Given two vectors of x-y data, bar produces a `stairstep' plot.
+#
+# If only one argument is given, it is taken as a vector of y-values
+# and the x coordiates are taken to be the indices of the elements.
+#
+# If two output arguments are specified, the data are generated but
+# not plotted.  For example,
+#
+#   bar (x, y);
+#
+# and
+#
+#   [xs, ys] = stairs (x, y);
+#   plot (xs, ys);
+#
+# are equivalent.
+#
+# See also: plot, semilogx, semilogy, loglog, polar, mesh, contour,
+#           bar, gplot, gsplot, replot, xlabel, ylabel, title 
+
+
+  if (nargin == 1)
+    if (is_vector (x))
+      len = 2 * length (x);
+      xs = ys = zeros (len, 1);
+      k = 0;
+      for i = 1:2:len
+        xs(i) = k++;
+        ys(i) = x(k);
+        ys(i+1) = x(k);
+        xs(i+1) = k;
+      endfor
+    else
+      error ("stairs: argument must be a vector");
+    endif
+  elseif (nargin == 2)
+    if (is_vector (x) && is_vector (y))
+      xlen = length (x);
+      ylen = length (y);
+      if (xlen == ylen)
+        len = 2 * xlen;
+        xs = ys = zeros (len, 1);
+	k = 1;
+        len_m2 = len - 2;
+	for i = 1:2:len_m2
+	  xs(i) = x(k);
+	  ys(i) = y(k);
+	  ys(i+1) = y(k);
+          k++;
+	  xs(i+1) = x(k);
+          if (x(k) < x(k-1))
+            error ("stairs: x vector values must be in ascending order");
+          endif
+	endfor
+        xs(len-1) = x(xlen);
+        delta = x(xlen) - x(xlen-1);
+        xs(len) = x(xlen) + delta;
+        ys(len-1) = y(ylen);
+        ys(len) = y(ylen);
+      else
+        error ("stairs: arguments must be the same length");
+      endif
+    else
+      error ("stairs: arguments must be vectors");
+    endif
+  else
+    error ("usage: [xs, ys] = stairs (x, y)");
+  endif
+
+  if (nargout == 1)
+    plot (xs, ys);
+  endif
+
+endfunction