update

examples/.gitignore

@@ -0,0 +1,5 @@
+*.pyc
+eemd_example
+ceemdan_example
+eemd_example.out
+ceemdan_example.out

examples/CMakeLists.txt

@@ -0,0 +1,7 @@
+macro(add_example src)
+    add_executable(${src} ${src}.cpp)
+    target_link_libraries(${src} PUBLIC eemd)
+endmacro()
+
+add_example(eemd_example)
+add_example(ceemdan_example)

examples/README

@@ -0,0 +1,4 @@
+`eemd_example` is a simple example program for the C interface of libeemd. It
+writes its output to `eemd_example.out`. If you have installed `pyeemd` you can
+plot the results with the Python script `eemd_example_plot.py`. To compile the
+example please run `make`.

examples/ceemdan_example.cpp

@@ -0,0 +1,68 @@
+/* Copyright 2013 Perttu Luukko
+
+ * This file is part of libeemd.
+
+ * libeemd is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * libeemd is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with libeemd.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <gsl/gsl_math.h>
+const double pi = M_PI;
+
+#include "../src/eemd.h"
+
+const size_t ensemble_size = 500;
+const unsigned int S_number = 4;
+const unsigned int num_siftings = 50;
+const double noise_strength = 0.02;
+const unsigned long int rng_seed = 0;
+const char outfile[] = "ceemdan_example.out";
+
+const size_t N = 512;
+
+int main(void) {
+	libeemd_error_code err;
+	// As an example decompose a Dirac signal as in the original CEEMDAN paper
+	double* inp = (double*) malloc(N*sizeof(double));
+	memset(inp, 0x00, N*sizeof(double));
+	inp[N/2] = 1.0;
+	// Allocate memory for output data
+	size_t M = emd_num_imfs(N);
+	double* outp = (double*) malloc(M*N*sizeof(double));
+	// Run CEEMDAN
+	err = ceemdan(inp, N, outp, M, ensemble_size, noise_strength, S_number, num_siftings, rng_seed);
+	if (err != EMD_SUCCESS) {
+		emd_report_if_error(err);
+		exit(1);
+	}
+	// Write output to file
+	FILE* fp = fopen(outfile, "w");
+	for (size_t j=0; j<N; j++) {
+		fprintf(fp, "%f ", inp[j]);
+	}
+	fprintf(fp, "\n");
+	for (size_t i=0; i<M; i++) {
+		for (size_t j=0; j<N; j++) {
+			fprintf(fp, "%f ", outp[i*N+j]);
+		}
+		fprintf(fp, "\n");
+	}
+	printf("Done!\n");
+	// Cleanup
+	fclose(fp);
+	free(inp); inp = NULL;
+	free(outp); outp = NULL;
+}

examples/ceemdan_example_plot.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python2
+
+# Copyright 2013 Perttu Luukko
+
+# This file is part of libeemd.
+# 
+# libeemd is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+# 
+# libeemd is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with libeemd.  If not, see <http://www.gnu.org/licenses/>.
+
+from numpy import loadtxt
+from pylab import plot, show
+from pyeemd.utils import plot_imfs
+
+def main():
+    data = loadtxt("ceemdan_example.out")
+    orig = data[0]
+    imfs = data[1:]
+    plot(orig, label="Original data")
+    plot_imfs(imfs)
+    show()
+
+if __name__ == "__main__":
+    main()

examples/eemd_example.cpp

@@ -0,0 +1,74 @@
+/* Copyright 2013 Perttu Luukko
+
+ * This file is part of libeemd.
+
+ * libeemd is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * libeemd is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with libeemd.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <gsl/gsl_math.h>
+const double pi = M_PI;
+
+#include "../src/eemd.h"
+
+const size_t ensemble_size = 250;
+const unsigned int S_number = 4;
+const unsigned int num_siftings = 50;
+const double noise_strength = 0.2;
+const unsigned long int rng_seed = 0;
+const char outfile[] = "eemd_example.out";
+
+// An example signal to decompose
+const size_t N = 1024;
+static inline double input_signal(double x) {
+	const double omega = 2*pi/(N-1);
+	return sin(17*omega*x)+0.5*(1.0-exp(-0.002*x))*sin(51*omega*x+1);
+}
+
+int main(void) {
+	libeemd_error_code err;
+	// Define input data
+	double* inp = (double*) malloc(N*sizeof(double));
+	for (size_t i=0; i<N; i++) {
+		inp[i] = input_signal((double)i);
+	}
+	// Allocate memory for output data
+	size_t M = emd_num_imfs(N);
+	double* outp = (double*) malloc(M*N*sizeof(double));
+	// Run eemd
+	err = eemd(inp, N, outp, M, ensemble_size, noise_strength, S_number, num_siftings, rng_seed);
+	if (err != EMD_SUCCESS) {
+		emd_report_if_error(err);
+		exit(1);
+	}
+	// Write output to file
+	FILE* fp = fopen(outfile, "w");
+	for (size_t j=0; j<N; j++) {
+		fprintf(fp, "%f ", inp[j]);
+	}
+	fprintf(fp, "\n");
+	for (size_t i=0; i<M; i++) {
+		for (size_t j=0; j<N; j++) {
+			fprintf(fp, "%f ", outp[i*N+j]);
+		}
+		fprintf(fp, "\n");
+	}
+	printf("Done!\n");
+	// Cleanup
+	fclose(fp);
+	free(inp); inp = NULL;
+	free(outp); outp = NULL;
+}

examples/eemd_example_plot.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python2
+
+# Copyright 2013 Perttu Luukko
+
+# This file is part of libeemd.
+# 
+# libeemd is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+# 
+# libeemd is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with libeemd.  If not, see <http://www.gnu.org/licenses/>.
+
+from numpy import loadtxt
+from pylab import plot, show
+from pyeemd.utils import plot_imfs
+
+def main():
+    data = loadtxt("eemd_example.out")
+    orig = data[0]
+    imfs = data[1:]
+    plot(orig, label="Original data")
+    plot_imfs(imfs)
+    show()
+
+if __name__ == "__main__":
+    main()