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perl/Examples/Chap7/slope0

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+
+
+###
+### slope0
+###
+
+## Chapter 7 section 1
+
+sub slope {
+  my $f = shift;
+  my $e = 0.00000095367431640625;
+  return sub {
+    my $x = shift;
+    ($f->($x+$e) - $f->($x-$e)) / (2*$e);
+  };
+}