again, I missed a few. This should now be complete!

svn path=/trunk/externals/bbogart/chaos/; revision=1053

5 files changed, 946 insertions, 0 deletions

diff --git a/logistic.c b/logistic.c
new file mode 100644
index 0000000..509bfb3
--- /dev/null
+++ b/logistic.c
@@ -0,0 +1,247 @@
+/* logistic Attractor PD External */
+/* Copyright Michael McGonagle, from ??????, 2003 */
+/* This program is distributed under the params of the GNU Public License */
+
+///////////////////////////////////////////////////////////////////////////////////
+/* This file is part of Chaos PD Externals.                                      */
+/*                                                                               */
+/* Chaos PD Externals are free software; you can redistribute them and/or modify */
+/* them under the terms of the GNU General Public License as published by        */
+/* the Free Software Foundation; either version 2 of the License, or             */
+/* (at your option) any later version.                                           */
+/*                                                                               */
+/* Chaos PD Externals are distributed in the hope that they 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 the Chaos PD Externals; if not, write to the Free Software         */
+/* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA     */
+///////////////////////////////////////////////////////////////////////////////////
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <time.h>
+#include "lyapunov.h"
+
+#define M_a_lo 0
+#define M_a_hi 4
+
+#define M_a 0
+
+#define M_x 0
+
+#define M_param_count 1
+#define M_var_count 1
+#define M_search_count 3
+#define M_failure_limit 1000
+
+static char *version = "logistic v0.0, by Michael McGonagle, from ??????, 2003";
+
+t_class *logistic_class;
+
+typedef struct logistic_struct {
+	t_object x_obj;
+
+	double vars[M_var_count];
+	double vars_init[M_var_count];
+	t_atom vars_out[M_var_count];
+	t_outlet *vars_outlet;
+	
+	t_atom search_out[M_search_count];
+	t_outlet *search_outlet;
+	
+	double a, a_lo, a_hi;
+	t_atom params_out[M_param_count];
+	t_outlet *params_outlet;
+	double lyap_exp, lyap_lo, lyap_hi, lyap_limit, failure_ratio;
+} logistic_struct;
+
+static void calc(logistic_struct *logistic, double *vars) {
+	double x_0;
+	x_0 =logistic -> a*vars[M_x]*(1.0-vars[M_x]);
+	vars[M_x] = x_0;
+} // end calc
+
+static void calculate(logistic_struct *logistic) {
+	calc(logistic, logistic -> vars);
+	outlet_float(logistic -> x_obj.ob_outlet, logistic -> vars[M_x]);
+} // end calculate
+
+static void reset(logistic_struct *logistic, t_symbol *s, int argc, t_atom *argv) {
+	if (argc == M_var_count) {
+		logistic -> vars[M_x] = (double) atom_getfloatarg(M_x, argc, argv);
+	} else {
+		logistic -> vars[M_x] = logistic -> vars_init[M_x];
+	} // end if
+} // end reset
+
+static char *classify(logistic_struct *logistic) {
+	static char buff[2];
+	char *c = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+	buff[0] = c[(int) (((logistic -> a - M_a_lo) * (1.0 / (M_a_hi - M_a_lo))) * 26)];
+	buff[1] = '\0';
+	return buff;
+}
+
+static void make_results(logistic_struct *logistic) {
+	SETFLOAT(&logistic -> search_out[0], logistic -> lyap_exp);
+	SETSYMBOL(&logistic -> search_out[1], gensym(classify(logistic)));
+	SETFLOAT(&logistic -> search_out[2], logistic -> failure_ratio);
+	SETFLOAT(&logistic -> vars_out[M_x], logistic -> vars[M_x]);
+	SETFLOAT(&logistic -> params_out[M_a], logistic -> a);
+	outlet_list(logistic -> params_outlet, gensym("list"), M_param_count, logistic -> params_out);
+	outlet_list(logistic -> vars_outlet, gensym("list"), M_var_count, logistic -> vars_out);
+}
+
+static void show(logistic_struct *logistic) {
+	make_results(logistic);
+	outlet_anything(logistic -> search_outlet, gensym("show"), M_search_count, logistic -> search_out);
+}
+
+static void param(logistic_struct *logistic, t_symbol *s, int argc, t_atom *argv) {
+	if (argc != 1) {
+		post("Incorrect number of arguments for logistic fractal. Expecting 1 arguments.");
+		return;
+	}
+	logistic -> a = (double) atom_getfloatarg(0, argc, argv);
+}
+
+static void seed(logistic_struct *logistic, t_symbol *s, int argc, t_atom *argv) {
+	if (argc > 0) {
+		srand48(((unsigned int)time(0))|1);
+	} else {
+		srand48((unsigned int) atom_getfloatarg(0, argc, argv));
+	}
+}
+
+static void lyap(logistic_struct *logistic, t_floatarg l, t_floatarg h, t_floatarg lim) {
+	logistic -> lyap_lo = l;
+	logistic -> lyap_hi = h;
+	logistic -> lyap_limit = (double) ((int) lim);
+}
+
+static void elyap(logistic_struct *logistic) {
+	double results[M_var_count];
+	int i;
+	if (lyapunov_full((void *) logistic, (t_gotfn) calc, M_var_count, logistic -> vars, results) != NULL) {
+		post("elyapunov:");
+		for(i = 0; i < M_var_count; i++) { post("%d: %3.80f", i, results[i]); }
+	}
+}
+
+static void limiter(logistic_struct *logistic) {
+	if (logistic -> a_lo < M_a_lo) { logistic -> a_lo = M_a_lo; }
+	if (logistic -> a_lo > M_a_hi) { logistic -> a_lo = M_a_hi; }
+	if (logistic -> a_hi < M_a_lo) { logistic -> a_hi = M_a_lo; }
+	if (logistic -> a_hi > M_a_hi) { logistic -> a_hi = M_a_hi; }
+}
+
+static void constrain(logistic_struct *logistic, t_symbol *s, int argc, t_atom *argv) {
+	int i;
+	t_atom *arg = argv;
+	if (argc == 0) {
+		// reset to full limits of search ranges
+		logistic -> a_lo = M_a_lo;
+		logistic -> a_hi = M_a_hi;
+		return;
+	}
+	if (argc == 1) {
+		// set the ranges based on percentage of full range
+		double percent = atom_getfloat(arg);
+		double a_spread = ((M_a_hi - M_a_lo) * percent) / 2;
+		logistic -> a_lo = logistic -> a - a_spread;
+		logistic -> a_hi = logistic -> a + a_spread;
+		limiter(logistic);
+		return;
+	}
+	if (argc != M_param_count * 2) {
+		post("Invalid number of arguments for logistic constraints, requires 2 values, got %d", argc);
+		return;
+	}
+	logistic -> a_lo = atom_getfloat(arg++);
+	logistic -> a_hi = atom_getfloat(arg++);
+	limiter(logistic);
+}
+
+static void search(logistic_struct *logistic, t_symbol *s, int argc, t_atom *argv) {
+	int not_found, not_expired = logistic -> lyap_limit;
+	int jump, i, iterations;
+	t_atom vars[M_var_count];
+	double temp_a = logistic -> a;
+	if (argc > 0) {
+		for (i = 0; i < M_var_count; i++) {
+			SETFLOAT(&vars[i], atom_getfloatarg(i, argc, argv));
+		}
+	} else {
+		for (i = 0; i < M_var_count; i++) {
+			SETFLOAT(&vars[i], logistic -> vars_init[i]);
+		}
+	}
+	do {
+		jump = 500;
+		not_found = 0;
+		iterations = 10000;
+		bad_params:
+		logistic -> a = (drand48() * (logistic -> a_hi - logistic -> a_lo)) + logistic -> a_lo;
+		// put any preliminary checks specific to this fractal to eliminate bad_params
+
+		reset(logistic, NULL, argc, vars);
+		do { calc(logistic, logistic -> vars); } while(jump--);
+		logistic -> lyap_exp = lyapunov((void *) logistic, (t_gotfn) calc, M_var_count, (double *) logistic -> vars);
+		if (isnan(logistic -> lyap_exp)) { not_found = 1; }
+		if (logistic -> lyap_exp < logistic -> lyap_lo || logistic -> lyap_exp > logistic -> lyap_hi) { not_found = 1; }
+		not_expired--;
+	} while(not_found && not_expired);
+	reset(logistic, NULL, argc, vars);
+	if (!not_expired) {
+		post("Could not find a fractal after %d attempts.", (int) logistic -> lyap_limit);
+		post("Try using wider constraints.");
+		logistic -> a = temp_a;
+		outlet_anything(logistic -> search_outlet, gensym("invalid"), 0, NULL);
+	} else {
+		logistic -> failure_ratio = (logistic -> lyap_limit - not_expired) / logistic -> lyap_limit;
+		make_results(logistic);
+		outlet_anything(logistic -> search_outlet, gensym("search"), M_search_count, logistic -> search_out);
+	}
+}
+
+void *logistic_new(t_symbol *s, int argc, t_atom *argv) {
+	logistic_struct *logistic = (logistic_struct *) pd_new(logistic_class);
+	if (logistic != NULL) {
+		outlet_new(&logistic -> x_obj, &s_float);
+		logistic -> search_outlet = outlet_new(&logistic -> x_obj, &s_list);
+		logistic -> vars_outlet = outlet_new(&logistic -> x_obj, &s_list);
+		logistic -> params_outlet = outlet_new(&logistic -> x_obj, &s_list);
+		if (argc == M_param_count + M_var_count) {
+			logistic -> vars_init[M_x] = logistic -> vars[M_x] = (double) atom_getfloatarg(0, argc, argv);
+			logistic -> a = (double) atom_getfloatarg(1, argc, argv);
+		} else {
+			if (argc != 0 && argc != M_param_count + M_var_count) {
+				post("Incorrect number of arguments for logistic fractal. Expecting 2 arguments.");
+			}
+			logistic -> vars_init[M_x] = 0.1;
+			logistic -> a = 4;
+		}
+		constrain(logistic, NULL, 0, NULL);
+		lyap(logistic, -1000000.0, 1000000.0, M_failure_limit);
+	}
+	return (void *)logistic;
+}
+
+void logistic_setup(void) {
+	logistic_class = class_new(gensym("logistic"), (t_newmethod) logistic_new, 0, sizeof(logistic_struct), 0, A_GIMME, 0);
+	class_addbang(logistic_class, (t_method) calculate);
+	class_addmethod(logistic_class, (t_method) reset, gensym("reset"), A_GIMME, 0);
+	class_addmethod(logistic_class, (t_method) show, gensym("show"), 0);
+	class_addmethod(logistic_class, (t_method) param, gensym("param"), A_GIMME, 0);
+	class_addmethod(logistic_class, (t_method) seed, gensym("seed"), A_GIMME, 0);
+	class_addmethod(logistic_class, (t_method) lyap, gensym("lyapunov"), A_DEFFLOAT, A_DEFFLOAT, A_DEFFLOAT, 0);
+	class_addmethod(logistic_class, (t_method) elyap, gensym("elyapunov"), 0);
+	class_addmethod(logistic_class, (t_method) search, gensym("search"), A_GIMME, 0);
+	class_addmethod(logistic_class, (t_method) constrain, gensym("constrain"), A_GIMME, 0);
+	class_sethelpsymbol(logistic_class, gensym("help-logistic.pd"));
+}
+
diff --git a/lotka_volterra.c b/lotka_volterra.c
new file mode 100644
index 0000000..ecb4b75
--- /dev/null
+++ b/lotka_volterra.c
@@ -0,0 +1,325 @@
+/* lotkavolterra Attractor PD External */
+/* Copyright Michael McGonagle, 2003 */
+/* This program is distributed under the params of the GNU Public License */
+
+///////////////////////////////////////////////////////////////////////////////////
+/* This file is part of Chaos PD Externals.                                      */
+/*                                                                               */
+/* Chaos PD Externals are free software; you can redistribute them and/or modify */
+/* them under the terms of the GNU General Public License as published by        */
+/* the Free Software Foundation; either version 2 of the License, or             */
+/* (at your option) any later version.                                           */
+/*                                                                               */
+/* Chaos PD Externals are distributed in the hope that they 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 the Chaos PD Externals; if not, write to the Free Software         */
+/* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA     */
+///////////////////////////////////////////////////////////////////////////////////
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <time.h>
+#include "lyapunov.h"
+
+#define M_a_lo -1000
+#define M_a_hi 1000
+#define M_b_lo -1000
+#define M_b_hi 1000
+#define M_c_lo -1000
+#define M_c_hi 1000
+#define M_e_lo -1000
+#define M_e_hi 1000
+
+#define M_a 0
+#define M_b 1
+#define M_c 2
+#define M_e 3
+
+#define M_r 0
+#define M_f 1
+
+#define M_param_count 4
+#define M_var_count 2
+#define M_search_count 3
+#define M_failure_limit 1000
+
+static char *version = "lotkavolterra v0.0, by Michael McGonagle, 2003";
+
+t_class *lotkavolterra_class;
+
+typedef struct lotkavolterra_struct {
+	t_object x_obj;
+
+	double vars[M_var_count];
+	double vars_init[M_var_count];
+	t_atom vars_out[M_var_count];
+	t_outlet *vars_outlet;
+	
+	t_atom search_out[M_search_count];
+	t_outlet *search_outlet;
+	
+	double a, a_lo, a_hi, b, b_lo, b_hi, c, c_lo, c_hi, e, e_lo, e_hi;
+	t_atom params_out[M_param_count];
+	t_outlet *params_outlet;
+	double lyap_exp, lyap_lo, lyap_hi, lyap_limit, failure_ratio;
+	
+	t_outlet *outlets[M_var_count - 1];
+} lotkavolterra_struct;
+
+static void calc(lotkavolterra_struct *lotkavolterra, double *vars) {
+	double r_0, f_0;
+	r_0 =vars[M_r]+lotkavolterra -> a*vars[M_r]-lotkavolterra -> b*vars[M_r]*vars[M_f];
+	f_0 =vars[M_f]+lotkavolterra -> e*lotkavolterra -> b*vars[M_r]*vars[M_f]-lotkavolterra -> c*vars[M_f];
+	vars[M_r] = r_0;
+	vars[M_f] = f_0;
+} // end calc
+
+static void calculate(lotkavolterra_struct *lotkavolterra) {
+	calc(lotkavolterra, lotkavolterra -> vars);
+	outlet_float(lotkavolterra -> x_obj.ob_outlet, lotkavolterra -> vars[M_r]);
+	outlet_float(lotkavolterra -> outlets[M_f - 1], lotkavolterra -> vars[M_f]);
+} // end calculate
+
+static void reset(lotkavolterra_struct *lotkavolterra, t_symbol *s, int argc, t_atom *argv) {
+	if (argc == M_var_count) {
+		lotkavolterra -> vars[M_r] = (double) atom_getfloatarg(M_r, argc, argv);
+		lotkavolterra -> vars[M_f] = (double) atom_getfloatarg(M_f, argc, argv);
+	} else {
+		lotkavolterra -> vars[M_r] = lotkavolterra -> vars_init[M_r];
+		lotkavolterra -> vars[M_f] = lotkavolterra -> vars_init[M_f];
+	} // end if
+} // end reset
+
+static char *classify(lotkavolterra_struct *lotkavolterra) {
+	static char buff[5];
+	char *c = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+	buff[0] = c[(int) (((lotkavolterra -> a - M_a_lo) * (1.0 / (M_a_hi - M_a_lo))) * 26)];
+	buff[1] = c[(int) (((lotkavolterra -> b - M_b_lo) * (1.0 / (M_b_hi - M_b_lo))) * 26)];
+	buff[2] = c[(int) (((lotkavolterra -> c - M_c_lo) * (1.0 / (M_c_hi - M_c_lo))) * 26)];
+	buff[3] = c[(int) (((lotkavolterra -> e - M_e_lo) * (1.0 / (M_e_hi - M_e_lo))) * 26)];
+	buff[4] = '\0';
+	return buff;
+}
+
+static void make_results(lotkavolterra_struct *lotkavolterra) {
+	SETFLOAT(&lotkavolterra -> search_out[0], lotkavolterra -> lyap_exp);
+	SETSYMBOL(&lotkavolterra -> search_out[1], gensym(classify(lotkavolterra)));
+	SETFLOAT(&lotkavolterra -> search_out[2], lotkavolterra -> failure_ratio);
+	SETFLOAT(&lotkavolterra -> vars_out[M_r], lotkavolterra -> vars[M_r]);
+	SETFLOAT(&lotkavolterra -> vars_out[M_f], lotkavolterra -> vars[M_f]);
+	SETFLOAT(&lotkavolterra -> params_out[M_a], lotkavolterra -> a);
+	SETFLOAT(&lotkavolterra -> params_out[M_b], lotkavolterra -> b);
+	SETFLOAT(&lotkavolterra -> params_out[M_c], lotkavolterra -> c);
+	SETFLOAT(&lotkavolterra -> params_out[M_e], lotkavolterra -> e);
+	outlet_list(lotkavolterra -> params_outlet, gensym("list"), M_param_count, lotkavolterra -> params_out);
+	outlet_list(lotkavolterra -> vars_outlet, gensym("list"), M_var_count, lotkavolterra -> vars_out);
+}
+
+static void show(lotkavolterra_struct *lotkavolterra) {
+	make_results(lotkavolterra);
+	outlet_anything(lotkavolterra -> search_outlet, gensym("show"), M_search_count, lotkavolterra -> search_out);
+}
+
+static void param(lotkavolterra_struct *lotkavolterra, t_symbol *s, int argc, t_atom *argv) {
+	if (argc != 4) {
+		post("Incorrect number of arguments for lotkavolterra fractal. Expecting 4 arguments.");
+		return;
+	}
+	lotkavolterra -> a = (double) atom_getfloatarg(0, argc, argv);
+	lotkavolterra -> b = (double) atom_getfloatarg(1, argc, argv);
+	lotkavolterra -> c = (double) atom_getfloatarg(2, argc, argv);
+	lotkavolterra -> e = (double) atom_getfloatarg(3, argc, argv);
+}
+
+static void seed(lotkavolterra_struct *lotkavolterra, t_symbol *s, int argc, t_atom *argv) {
+	if (argc > 0) {
+		srand48(((unsigned int)time(0))|1);
+	} else {
+		srand48((unsigned int) atom_getfloatarg(0, argc, argv));
+	}
+}
+
+static void lyap(lotkavolterra_struct *lotkavolterra, t_floatarg l, t_floatarg h, t_floatarg lim) {
+	lotkavolterra -> lyap_lo = l;
+	lotkavolterra -> lyap_hi = h;
+	lotkavolterra -> lyap_limit = (double) ((int) lim);
+}
+
+static void elyap(lotkavolterra_struct *lotkavolterra) {
+	double results[M_var_count];
+	int i;
+	if (lyapunov_full((void *) lotkavolterra, (t_gotfn) calc, M_var_count, lotkavolterra -> vars, results) != NULL) {
+		post("elyapunov:");
+		for(i = 0; i < M_var_count; i++) { post("%d: %3.80f", i, results[i]); }
+	}
+}
+
+static void limiter(lotkavolterra_struct *lotkavolterra) {
+	if (lotkavolterra -> a_lo < M_a_lo) { lotkavolterra -> a_lo = M_a_lo; }
+	if (lotkavolterra -> a_lo > M_a_hi) { lotkavolterra -> a_lo = M_a_hi; }
+	if (lotkavolterra -> a_hi < M_a_lo) { lotkavolterra -> a_hi = M_a_lo; }
+	if (lotkavolterra -> a_hi > M_a_hi) { lotkavolterra -> a_hi = M_a_hi; }
+	if (lotkavolterra -> b_lo < M_b_lo) { lotkavolterra -> b_lo = M_b_lo; }
+	if (lotkavolterra -> b_lo > M_b_hi) { lotkavolterra -> b_lo = M_b_hi; }
+	if (lotkavolterra -> b_hi < M_b_lo) { lotkavolterra -> b_hi = M_b_lo; }
+	if (lotkavolterra -> b_hi > M_b_hi) { lotkavolterra -> b_hi = M_b_hi; }
+	if (lotkavolterra -> c_lo < M_c_lo) { lotkavolterra -> c_lo = M_c_lo; }
+	if (lotkavolterra -> c_lo > M_c_hi) { lotkavolterra -> c_lo = M_c_hi; }
+	if (lotkavolterra -> c_hi < M_c_lo) { lotkavolterra -> c_hi = M_c_lo; }
+	if (lotkavolterra -> c_hi > M_c_hi) { lotkavolterra -> c_hi = M_c_hi; }
+	if (lotkavolterra -> e_lo < M_e_lo) { lotkavolterra -> e_lo = M_e_lo; }
+	if (lotkavolterra -> e_lo > M_e_hi) { lotkavolterra -> e_lo = M_e_hi; }
+	if (lotkavolterra -> e_hi < M_e_lo) { lotkavolterra -> e_hi = M_e_lo; }
+	if (lotkavolterra -> e_hi > M_e_hi) { lotkavolterra -> e_hi = M_e_hi; }
+}
+
+static void constrain(lotkavolterra_struct *lotkavolterra, t_symbol *s, int argc, t_atom *argv) {
+	int i;
+	t_atom *arg = argv;
+	if (argc == 0) {
+		// reset to full limits of search ranges
+		lotkavolterra -> a_lo = M_a_lo;
+		lotkavolterra -> a_hi = M_a_hi;
+		lotkavolterra -> b_lo = M_b_lo;
+		lotkavolterra -> b_hi = M_b_hi;
+		lotkavolterra -> c_lo = M_c_lo;
+		lotkavolterra -> c_hi = M_c_hi;
+		lotkavolterra -> e_lo = M_e_lo;
+		lotkavolterra -> e_hi = M_e_hi;
+		return;
+	}
+	if (argc == 1) {
+		// set the ranges based on percentage of full range
+		double percent = atom_getfloat(arg);
+		double a_spread = ((M_a_hi - M_a_lo) * percent) / 2;
+		double b_spread = ((M_b_hi - M_b_lo) * percent) / 2;
+		double c_spread = ((M_c_hi - M_c_lo) * percent) / 2;
+		double e_spread = ((M_e_hi - M_e_lo) * percent) / 2;
+		lotkavolterra -> a_lo = lotkavolterra -> a - a_spread;
+		lotkavolterra -> a_hi = lotkavolterra -> a + a_spread;
+		lotkavolterra -> b_lo = lotkavolterra -> b - b_spread;
+		lotkavolterra -> b_hi = lotkavolterra -> b + b_spread;
+		lotkavolterra -> c_lo = lotkavolterra -> c - c_spread;
+		lotkavolterra -> c_hi = lotkavolterra -> c + c_spread;
+		lotkavolterra -> e_lo = lotkavolterra -> e - e_spread;
+		lotkavolterra -> e_hi = lotkavolterra -> e + e_spread;
+		limiter(lotkavolterra);
+		return;
+	}
+	if (argc != M_param_count * 2) {
+		post("Invalid number of arguments for lotkavolterra constraints, requires 8 values, got %d", argc);
+		return;
+	}
+	lotkavolterra -> a_lo = atom_getfloat(arg++);
+	lotkavolterra -> a_hi = atom_getfloat(arg++);
+	lotkavolterra -> b_lo = atom_getfloat(arg++);
+	lotkavolterra -> b_hi = atom_getfloat(arg++);
+	lotkavolterra -> c_lo = atom_getfloat(arg++);
+	lotkavolterra -> c_hi = atom_getfloat(arg++);
+	lotkavolterra -> e_lo = atom_getfloat(arg++);
+	lotkavolterra -> e_hi = atom_getfloat(arg++);
+	limiter(lotkavolterra);
+}
+
+static void search(lotkavolterra_struct *lotkavolterra, t_symbol *s, int argc, t_atom *argv) {
+	int not_found, not_expired = lotkavolterra -> lyap_limit;
+	int jump, i, iterations;
+	t_atom vars[M_var_count];
+	double temp_a = lotkavolterra -> a;
+	double temp_b = lotkavolterra -> b;
+	double temp_c = lotkavolterra -> c;
+	double temp_e = lotkavolterra -> e;
+	if (argc > 0) {
+		for (i = 0; i < M_var_count; i++) {
+			SETFLOAT(&vars[i], atom_getfloatarg(i, argc, argv));
+		}
+	} else {
+		for (i = 0; i < M_var_count; i++) {
+			SETFLOAT(&vars[i], lotkavolterra -> vars_init[i]);
+		}
+	}
+	do {
+		jump = 500;
+		not_found = 0;
+		iterations = 10000;
+		bad_params:
+		lotkavolterra -> a = (drand48() * (lotkavolterra -> a_hi - lotkavolterra -> a_lo)) + lotkavolterra -> a_lo;
+		lotkavolterra -> b = (drand48() * (lotkavolterra -> b_hi - lotkavolterra -> b_lo)) + lotkavolterra -> b_lo;
+		lotkavolterra -> c = (drand48() * (lotkavolterra -> c_hi - lotkavolterra -> c_lo)) + lotkavolterra -> c_lo;
+		lotkavolterra -> e = (drand48() * (lotkavolterra -> e_hi - lotkavolterra -> e_lo)) + lotkavolterra -> e_lo;
+		// put any preliminary checks specific to this fractal to eliminate bad_params
+
+		reset(lotkavolterra, NULL, argc, vars);
+		do { calc(lotkavolterra, lotkavolterra -> vars); } while(jump--);
+		lotkavolterra -> lyap_exp = lyapunov((void *) lotkavolterra, (t_gotfn) calc, M_var_count, (double *) lotkavolterra -> vars);
+		if (isnan(lotkavolterra -> lyap_exp)) { not_found = 1; }
+		if (lotkavolterra -> lyap_exp < lotkavolterra -> lyap_lo || lotkavolterra -> lyap_exp > lotkavolterra -> lyap_hi) { not_found = 1; }
+		not_expired--;
+	} while(not_found && not_expired);
+	reset(lotkavolterra, NULL, argc, vars);
+	if (!not_expired) {
+		post("Could not find a fractal after %d attempts.", (int) lotkavolterra -> lyap_limit);
+		post("Try using wider constraints.");
+		lotkavolterra -> a = temp_a;
+		lotkavolterra -> b = temp_b;
+		lotkavolterra -> c = temp_c;
+		lotkavolterra -> e = temp_e;
+		outlet_anything(lotkavolterra -> search_outlet, gensym("invalid"), 0, NULL);
+	} else {
+		lotkavolterra -> failure_ratio = (lotkavolterra -> lyap_limit - not_expired) / lotkavolterra -> lyap_limit;
+		make_results(lotkavolterra);
+		outlet_anything(lotkavolterra -> search_outlet, gensym("search"), M_search_count, lotkavolterra -> search_out);
+	}
+}
+
+void *lotkavolterra_new(t_symbol *s, int argc, t_atom *argv) {
+	lotkavolterra_struct *lotkavolterra = (lotkavolterra_struct *) pd_new(lotkavolterra_class);
+	if (lotkavolterra != NULL) {
+		outlet_new(&lotkavolterra -> x_obj, &s_float);
+		lotkavolterra -> outlets[0] = outlet_new(&lotkavolterra -> x_obj, &s_float);
+		lotkavolterra -> search_outlet = outlet_new(&lotkavolterra -> x_obj, &s_list);
+		lotkavolterra -> vars_outlet = outlet_new(&lotkavolterra -> x_obj, &s_list);
+		lotkavolterra -> params_outlet = outlet_new(&lotkavolterra -> x_obj, &s_list);
+		if (argc == M_param_count + M_var_count) {
+			lotkavolterra -> vars_init[M_r] = lotkavolterra -> vars[M_r] = (double) atom_getfloatarg(0, argc, argv);
+			lotkavolterra -> vars_init[M_f] = lotkavolterra -> vars[M_f] = (double) atom_getfloatarg(1, argc, argv);
+			lotkavolterra -> a = (double) atom_getfloatarg(2, argc, argv);
+			lotkavolterra -> b = (double) atom_getfloatarg(3, argc, argv);
+			lotkavolterra -> c = (double) atom_getfloatarg(4, argc, argv);
+			lotkavolterra -> e = (double) atom_getfloatarg(5, argc, argv);
+		} else {
+			if (argc != 0 && argc != M_param_count + M_var_count) {
+				post("Incorrect number of arguments for lotkavolterra fractal. Expecting 6 arguments.");
+			}
+			lotkavolterra -> vars_init[M_r] = 0.1;
+			lotkavolterra -> vars_init[M_f] = 0.1;
+			lotkavolterra -> a = 0.04;
+			lotkavolterra -> b = 0.0005;
+			lotkavolterra -> c = 0.2;
+			lotkavolterra -> e = 0.1;
+		}
+		constrain(lotkavolterra, NULL, 0, NULL);
+		lyap(lotkavolterra, -1000000.0, 1000000.0, M_failure_limit);
+	}
+	return (void *)lotkavolterra;
+}
+
+void lotkavolterra_setup(void) {
+	lotkavolterra_class = class_new(gensym("lotkavolterra"), (t_newmethod) lotkavolterra_new, 0, sizeof(lotkavolterra_struct), 0, A_GIMME, 0);
+	class_addbang(lotkavolterra_class, (t_method) calculate);
+	class_addmethod(lotkavolterra_class, (t_method) reset, gensym("reset"), A_GIMME, 0);
+	class_addmethod(lotkavolterra_class, (t_method) show, gensym("show"), 0);
+	class_addmethod(lotkavolterra_class, (t_method) param, gensym("param"), A_GIMME, 0);
+	class_addmethod(lotkavolterra_class, (t_method) seed, gensym("seed"), A_GIMME, 0);
+	class_addmethod(lotkavolterra_class, (t_method) lyap, gensym("lyapunov"), A_DEFFLOAT, A_DEFFLOAT, A_DEFFLOAT, 0);
+	class_addmethod(lotkavolterra_class, (t_method) elyap, gensym("elyapunov"), 0);
+	class_addmethod(lotkavolterra_class, (t_method) search, gensym("search"), A_GIMME, 0);
+	class_addmethod(lotkavolterra_class, (t_method) constrain, gensym("constrain"), A_GIMME, 0);
+	class_sethelpsymbol(lotkavolterra_class, gensym("help-lotkavolterra.pd"));
+}
+
diff --git a/lyapunov.c b/lyapunov.c
new file mode 100644
index 0000000..04153ba
--- /dev/null
+++ b/lyapunov.c
@@ -0,0 +1,90 @@
+#include <stdio.h>
+#include <math.h>
+#include "lyapunov.h"
+
+#define LY_ITERATIONS 50000
+
+//#define LY_ABERATION 1e-6
+#define LY_ABERATION 10e-15
+
+/**
+ * this expects the fractal to already be stable (ie iterate it a few hundred/thousand times).
+ 
+ Steps as described by Julian Sprott
+ 1. Start with any initial condition in the basin of attraction
+ 2. Iterate until the orbit is on the attractor
+ 3. Select (almost any) nearby point (separated by d0)
+ 4. Advancce both orbits one iteration and calculate the new separation d1
+ 5. Evaluate log(d1/d0) in any convienient base
+ 6. Readjust one orbit so its separation is d0 in the same direction as d1
+ 7. Repeat steps 4-6 many times and calculate the average of step 5
+ */
+double lyapunov_eval(void *fractal, t_gotfn calc, int var_count, double *vars, double *test) {
+	int i, j;
+	double exponent = 0.0, sum = 0.0, d2, df, rs;
+	double diff[MAX_VARS];
+	
+	for(i = 0; i < LY_ITERATIONS; i++) {
+		// 4. iterate each set
+		calc(fractal, vars);
+		calc(fractal, test);
+		// 5. Evaluate
+		d2 = 0.0;
+		for(j = 0; j < var_count; j++) {
+			diff[j] = test[j] - vars[j];
+			//fprintf(stderr, "vars[%d] = %0.30f\n test[%d] = %0.30f\n  diff[%d] = %0.30f\n",
+			//	j, vars[j], j, test[j], j, diff[j]);
+			d2 += diff[j] * diff[j];
+		}
+		df = 1000000000000.0 * d2;
+		rs = 1.0 / sqrt(df);
+		sum += log(df);
+		exponent = 0.721347 * sum / i;
+		//fprintf(stderr, "%d\n  d2 = %0.30f\n  df = %0.30f\n  rs = %0.30f\n  sum = %0.30f\nexponent = %0.30f\n\n",
+		//	i, d2, df, rs, sum, exponent);
+		// 6. adjust the orbit under test
+		for(j = 0; j < var_count; j++) {
+			test[j] = vars[j] + (rs * (test[j] - vars[j]));
+		}
+	}
+	return exponent;
+}
+
+double lyapunov(void *fractal, t_gotfn calc, int var_count, double *vars) {
+	int i;
+	double test[MAX_VARS];
+	
+	// 1. + 2. 'vars' is expected to be ready to start computing
+	// 3. create a test set of variables
+	test[0] = vars[0] + LY_ABERATION;
+	for(i = 1; i < var_count; i++) { test[i] = vars[i]; }
+	
+	return lyapunov_eval(fractal, calc, var_count, vars, test);
+}
+
+double *lyapunov_full(void *fractal, t_gotfn calc, int var_count, double *vars, double *results) {
+	int i, j;
+	double initial[MAX_VARS];
+	double test[MAX_VARS];
+	
+	// save the starting values
+	for(i = 0; i < var_count; i++) {
+		initial[i] = vars[i];
+	}
+	for(i = 0; i < var_count; i++) {
+		// aberate each variable in turn
+		for(j = 0; j < var_count; j++) {
+			if (j == i) {
+				test[j] = vars[j] + LY_ABERATION;
+			} else {
+				test[j] = vars[j];
+			}
+		}
+		results[i] = lyapunov_eval(fractal, calc, var_count, vars, test);
+		// set the vars back the initial values
+		for(j = 0; j < var_count; j++) {
+			vars[j] = initial[j];
+		}
+	}
+	return results;
+}
diff --git a/lyapunov.h b/lyapunov.h
new file mode 100644
index 0000000..d6b71f5
--- /dev/null
+++ b/lyapunov.h
@@ -0,0 +1,25 @@
+/*
+ a test file for lyapunov.h
+ */
+
+#ifndef PD_VERSION
+#include "m_pd.h"
+#endif
+
+#define MAX_VARS 20
+
+/*
+ * fractal - pointer to the object under test
+ * calc - the iteration function
+ * var_count - the number of variables for this fractal class
+ * vars - pointer to the fractal variables array
+ */
+double lyapunov(void *fractal, t_gotfn calc, int var_count, double *vars);
+
+/*
+ * CAUTION: ON FRACTALS WITH LOTS OF VARIABLES, THIS WILL TAKE A WHILE.
+ * This is an experimental function to test the ability of the function to
+ * calculate an accurate exponent by aberating each variable in the fractal.
+ * returns 'results' on completion.
+ */
+double *lyapunov_full(void *fractal, t_gotfn calc, int var_count, double *vars, double *results);
diff --git a/martin.c b/martin.c
new file mode 100644
index 0000000..bc8b6ff
--- /dev/null
+++ b/martin.c
@@ -0,0 +1,259 @@
+/* martin Attractor PD External */
+/* Copyright Michael McGonagle, from ??????, 2003 */
+/* This program is distributed under the params of the GNU Public License */
+
+///////////////////////////////////////////////////////////////////////////////////
+/* This file is part of Chaos PD Externals.                                      */
+/*                                                                               */
+/* Chaos PD Externals are free software; you can redistribute them and/or modify */
+/* them under the terms of the GNU General Public License as published by        */
+/* the Free Software Foundation; either version 2 of the License, or             */
+/* (at your option) any later version.                                           */
+/*                                                                               */
+/* Chaos PD Externals are distributed in the hope that they 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 the Chaos PD Externals; if not, write to the Free Software         */
+/* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA     */
+///////////////////////////////////////////////////////////////////////////////////
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <time.h>
+#include "lyapunov.h"
+
+#define M_a_lo 0
+#define M_a_hi 1000
+
+#define M_a 0
+
+#define M_x 0
+#define M_y 1
+
+#define M_param_count 1
+#define M_var_count 2
+#define M_search_count 3
+#define M_failure_limit 1000
+
+static char *version = "martin v0.0, by Michael McGonagle, from ??????, 2003";
+
+t_class *martin_class;
+
+typedef struct martin_struct {
+	t_object x_obj;
+
+	double vars[M_var_count];
+	double vars_init[M_var_count];
+	t_atom vars_out[M_var_count];
+	t_outlet *vars_outlet;
+	
+	t_atom search_out[M_search_count];
+	t_outlet *search_outlet;
+	
+	double a, a_lo, a_hi;
+	t_atom params_out[M_param_count];
+	t_outlet *params_outlet;
+	double lyap_exp, lyap_lo, lyap_hi, lyap_limit, failure_ratio;
+	
+	t_outlet *outlets[M_var_count - 1];
+} martin_struct;
+
+static void calc(martin_struct *martin, double *vars) {
+	double x_0, y_0;
+	x_0 =vars[M_y]-sin(vars[M_x]);
+	y_0 =martin -> a-vars[M_x];
+	vars[M_x] = x_0;
+	vars[M_y] = y_0;
+} // end calc
+
+static void calculate(martin_struct *martin) {
+	calc(martin, martin -> vars);
+	outlet_float(martin -> x_obj.ob_outlet, martin -> vars[M_x]);
+	outlet_float(martin -> outlets[M_y - 1], martin -> vars[M_y]);
+} // end calculate
+
+static void reset(martin_struct *martin, t_symbol *s, int argc, t_atom *argv) {
+	if (argc == M_var_count) {
+		martin -> vars[M_x] = (double) atom_getfloatarg(M_x, argc, argv);
+		martin -> vars[M_y] = (double) atom_getfloatarg(M_y, argc, argv);
+	} else {
+		martin -> vars[M_x] = martin -> vars_init[M_x];
+		martin -> vars[M_y] = martin -> vars_init[M_y];
+	} // end if
+} // end reset
+
+static char *classify(martin_struct *martin) {
+	static char buff[2];
+	char *c = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+	buff[0] = c[(int) (((martin -> a - M_a_lo) * (1.0 / (M_a_hi - M_a_lo))) * 26)];
+	buff[1] = '\0';
+	return buff;
+}
+
+static void make_results(martin_struct *martin) {
+	SETFLOAT(&martin -> search_out[0], martin -> lyap_exp);
+	SETSYMBOL(&martin -> search_out[1], gensym(classify(martin)));
+	SETFLOAT(&martin -> search_out[2], martin -> failure_ratio);
+	SETFLOAT(&martin -> vars_out[M_x], martin -> vars[M_x]);
+	SETFLOAT(&martin -> vars_out[M_y], martin -> vars[M_y]);
+	SETFLOAT(&martin -> params_out[M_a], martin -> a);
+	outlet_list(martin -> params_outlet, gensym("list"), M_param_count, martin -> params_out);
+	outlet_list(martin -> vars_outlet, gensym("list"), M_var_count, martin -> vars_out);
+}
+
+static void show(martin_struct *martin) {
+	make_results(martin);
+	outlet_anything(martin -> search_outlet, gensym("show"), M_search_count, martin -> search_out);
+}
+
+static void param(martin_struct *martin, t_symbol *s, int argc, t_atom *argv) {
+	if (argc != 1) {
+		post("Incorrect number of arguments for martin fractal. Expecting 1 arguments.");
+		return;
+	}
+	martin -> a = (double) atom_getfloatarg(0, argc, argv);
+}
+
+static void seed(martin_struct *martin, t_symbol *s, int argc, t_atom *argv) {
+	if (argc > 0) {
+		srand48(((unsigned int)time(0))|1);
+	} else {
+		srand48((unsigned int) atom_getfloatarg(0, argc, argv));
+	}
+}
+
+static void lyap(martin_struct *martin, t_floatarg l, t_floatarg h, t_floatarg lim) {
+	martin -> lyap_lo = l;
+	martin -> lyap_hi = h;
+	martin -> lyap_limit = (double) ((int) lim);
+}
+
+static void elyap(martin_struct *martin) {
+	double results[M_var_count];
+	int i;
+	if (lyapunov_full((void *) martin, (t_gotfn) calc, M_var_count, martin -> vars, results) != NULL) {
+		post("elyapunov:");
+		for(i = 0; i < M_var_count; i++) { post("%d: %3.80f", i, results[i]); }
+	}
+}
+
+static void limiter(martin_struct *martin) {
+	if (martin -> a_lo < M_a_lo) { martin -> a_lo = M_a_lo; }
+	if (martin -> a_lo > M_a_hi) { martin -> a_lo = M_a_hi; }
+	if (martin -> a_hi < M_a_lo) { martin -> a_hi = M_a_lo; }
+	if (martin -> a_hi > M_a_hi) { martin -> a_hi = M_a_hi; }
+}
+
+static void constrain(martin_struct *martin, t_symbol *s, int argc, t_atom *argv) {
+	int i;
+	t_atom *arg = argv;
+	if (argc == 0) {
+		// reset to full limits of search ranges
+		martin -> a_lo = M_a_lo;
+		martin -> a_hi = M_a_hi;
+		return;
+	}
+	if (argc == 1) {
+		// set the ranges based on percentage of full range
+		double percent = atom_getfloat(arg);
+		double a_spread = ((M_a_hi - M_a_lo) * percent) / 2;
+		martin -> a_lo = martin -> a - a_spread;
+		martin -> a_hi = martin -> a + a_spread;
+		limiter(martin);
+		return;
+	}
+	if (argc != M_param_count * 2) {
+		post("Invalid number of arguments for martin constraints, requires 2 values, got %d", argc);
+		return;
+	}
+	martin -> a_lo = atom_getfloat(arg++);
+	martin -> a_hi = atom_getfloat(arg++);
+	limiter(martin);
+}
+
+static void search(martin_struct *martin, t_symbol *s, int argc, t_atom *argv) {
+	int not_found, not_expired = martin -> lyap_limit;
+	int jump, i, iterations;
+	t_atom vars[M_var_count];
+	double temp_a = martin -> a;
+	if (argc > 0) {
+		for (i = 0; i < M_var_count; i++) {
+			SETFLOAT(&vars[i], atom_getfloatarg(i, argc, argv));
+		}
+	} else {
+		for (i = 0; i < M_var_count; i++) {
+			SETFLOAT(&vars[i], martin -> vars_init[i]);
+		}
+	}
+	do {
+		jump = 500;
+		not_found = 0;
+		iterations = 10000;
+		bad_params:
+		martin -> a = (drand48() * (martin -> a_hi - martin -> a_lo)) + martin -> a_lo;
+		// put any preliminary checks specific to this fractal to eliminate bad_params
+
+		reset(martin, NULL, argc, vars);
+		do { calc(martin, martin -> vars); } while(jump--);
+		martin -> lyap_exp = lyapunov((void *) martin, (t_gotfn) calc, M_var_count, (double *) martin -> vars);
+		if (isnan(martin -> lyap_exp)) { not_found = 1; }
+		if (martin -> lyap_exp < martin -> lyap_lo || martin -> lyap_exp > martin -> lyap_hi) { not_found = 1; }
+		not_expired--;
+	} while(not_found && not_expired);
+	reset(martin, NULL, argc, vars);
+	if (!not_expired) {
+		post("Could not find a fractal after %d attempts.", (int) martin -> lyap_limit);
+		post("Try using wider constraints.");
+		martin -> a = temp_a;
+		outlet_anything(martin -> search_outlet, gensym("invalid"), 0, NULL);
+	} else {
+		martin -> failure_ratio = (martin -> lyap_limit - not_expired) / martin -> lyap_limit;
+		make_results(martin);
+		outlet_anything(martin -> search_outlet, gensym("search"), M_search_count, martin -> search_out);
+	}
+}
+
+void *martin_new(t_symbol *s, int argc, t_atom *argv) {
+	martin_struct *martin = (martin_struct *) pd_new(martin_class);
+	if (martin != NULL) {
+		outlet_new(&martin -> x_obj, &s_float);
+		martin -> outlets[0] = outlet_new(&martin -> x_obj, &s_float);
+		martin -> search_outlet = outlet_new(&martin -> x_obj, &s_list);
+		martin -> vars_outlet = outlet_new(&martin -> x_obj, &s_list);
+		martin -> params_outlet = outlet_new(&martin -> x_obj, &s_list);
+		if (argc == M_param_count + M_var_count) {
+			martin -> vars_init[M_x] = martin -> vars[M_x] = (double) atom_getfloatarg(0, argc, argv);
+			martin -> vars_init[M_y] = martin -> vars[M_y] = (double) atom_getfloatarg(1, argc, argv);
+			martin -> a = (double) atom_getfloatarg(2, argc, argv);
+		} else {
+			if (argc != 0 && argc != M_param_count + M_var_count) {
+				post("Incorrect number of arguments for martin fractal. Expecting 3 arguments.");
+			}
+			martin -> vars_init[M_x] = 0.01;
+			martin -> vars_init[M_y] = 0;
+			martin -> a = 3.14;
+		}
+		constrain(martin, NULL, 0, NULL);
+		lyap(martin, -1000000.0, 1000000.0, M_failure_limit);
+	}
+	return (void *)martin;
+}
+
+void martin_setup(void) {
+	martin_class = class_new(gensym("martin"), (t_newmethod) martin_new, 0, sizeof(martin_struct), 0, A_GIMME, 0);
+	class_addbang(martin_class, (t_method) calculate);
+	class_addmethod(martin_class, (t_method) reset, gensym("reset"), A_GIMME, 0);
+	class_addmethod(martin_class, (t_method) show, gensym("show"), 0);
+	class_addmethod(martin_class, (t_method) param, gensym("param"), A_GIMME, 0);
+	class_addmethod(martin_class, (t_method) seed, gensym("seed"), A_GIMME, 0);
+	class_addmethod(martin_class, (t_method) lyap, gensym("lyapunov"), A_DEFFLOAT, A_DEFFLOAT, A_DEFFLOAT, 0);
+	class_addmethod(martin_class, (t_method) elyap, gensym("elyapunov"), 0);
+	class_addmethod(martin_class, (t_method) search, gensym("search"), A_GIMME, 0);
+	class_addmethod(martin_class, (t_method) constrain, gensym("constrain"), A_GIMME, 0);
+	class_sethelpsymbol(martin_class, gensym("help-martin.pd"));
+}
+