animated-resizing: enhance output

Show the average and standard deviation of the latency in addition to
the frame rate. Add options to print the output in machine-readable form,
and to control the frequency and total number of statistics that will be
output.

https://bugzilla.gnome.org/show_bug.cgi?id=685460

1 files changed, 43 insertions, 0 deletions

diff --git a/tests/variable.c b/tests/variable.c
new file mode 100644
index 0000000000..9ce5d5d6ab
--- /dev/null
+++ b/tests/variable.c
@@ -0,0 +1,43 @@
+/* -*- mode: C; c-basic-offset: 2; indent-tabs-mode: nil; -*- */
+
+#include <math.h>
+#include "variable.h"
+
+void
+variable_add_weighted (Variable *variable,
+                       double    value,
+                       double    weight)
+{
+  variable->weight += weight;
+  variable->sum += weight * value;
+  variable->sum2 += weight * value * value;
+}
+
+void
+variable_add (Variable *variable,
+              double    value)
+{
+  variable_add_weighted (variable, value, 1.);
+}
+
+double
+variable_mean (Variable *variable)
+{
+  return variable->sum / variable->weight;
+}
+
+double
+variable_standard_deviation (Variable *variable)
+{
+  double mean = variable_mean (variable);
+  return sqrt (variable->sum2 / variable->weight - mean * mean);
+}
+
+void
+variable_reset (Variable *variable)
+{
+  variable->weight = 0;
+  variable->sum = 0;
+  variable->sum2 = 0;
+}
+