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+#!/usr/bin/python
+# The contents of this file are in the public domain. See LICENSE_FOR_EXAMPLE_PROGRAMS.txt
+#
+#
+# This is an example illustrating the use of the global optimization routine,
+# find_min_global(), from the dlib C++ Library. This is a tool for finding the
+# inputs to a function that result in the function giving its minimal output.
+# This is a very useful tool for hyper parameter search when applying machine
+# learning methods. There are also many other applications for this kind of
+# general derivative free optimization. However, in this example program, we
+# simply show how to call the method. For that, we use a common global
+# optimization test function, as you can see below.
+#
+#
+# COMPILING/INSTALLING THE DLIB PYTHON INTERFACE
+# You can install dlib using the command:
+# pip install dlib
+#
+# Alternatively, if you want to compile dlib yourself then go into the dlib
+# root folder and run:
+# python setup.py install
+#
+# Compiling dlib should work on any operating system so long as you have
+# CMake installed. On Ubuntu, this can be done easily by running the
+# command:
+# sudo apt-get install cmake
+#
+
+import dlib
+from math import sin,cos,pi,exp,sqrt
+
+# This is a standard test function for these kinds of optimization problems.
+# It has a bunch of local minima, with the global minimum resulting in
+# holder_table()==-19.2085025679.
+def holder_table(x0,x1):
+ return -abs(sin(x0)*cos(x1)*exp(abs(1-sqrt(x0*x0+x1*x1)/pi)))
+
+# Find the optimal inputs to holder_table(). The print statements that follow
+# show that find_min_global() finds the optimal settings to high precision.
+x,y = dlib.find_min_global(holder_table,
+ [-10,-10], # Lower bound constraints on x0 and x1 respectively
+ [10,10], # Upper bound constraints on x0 and x1 respectively
+ 80) # The number of times find_min_global() will call holder_table()
+
+print("optimal inputs: {}".format(x));
+print("optimal output: {}".format(y));
+