generate beautiful pictures of the complex Anosov set

This commit is contained in:
Florian Stecker 2022-06-15 12:20:45 +02:00
parent 729d1a10b7
commit 429f0890d6
6 changed files with 362 additions and 156 deletions

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@ -8,35 +8,39 @@
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <time.h>
#define LOOP(i,n) for(int i = 0; i < (n); i++)
#define SWAP(t,x,y) do { t _tmp = (x); (x) = (y); (y) = _tmp; } while (0);
//#define INFO(msg, ...) fprintf(stderr, "[%10.3f] " msg, runtime(), ##__VA_ARGS__)
#define INFO(msg, ...)
/*
Elements up to length 0: 1
Elements up to length 1: 4
Elements up to length 2: 10
Elements up to length 3: 22
Elements up to length 4: 46
Elements up to length 5: 91
Elements up to length 6: 175
Elements up to length 7: 334
Elements up to length 8: 634
Elements up to length 9: 1198
Elements up to length 10: 2260
Elements up to length 11: 4261
Elements up to length 12: 8029
Elements up to length 13: 15124
Elements up to length 14: 28486
Elements up to length 15: 53650
Elements up to length 16: 101038
Elements up to length 17: 190279
Elements up to length 18: 358339
Elements up to length 19: 674830
Elements up to length 20: 1270846
Elements up to length 21: 2393266
Elements up to length 22: 4507012
Elements up to length 23: 8487625
Number of elements
up to length 0: 1
up to length 1: 4
up to length 2: 10
up to length 3: 22
up to length 4: 46
up to length 5: 91
up to length 6: 175
up to length 7: 334
up to length 8: 634
up to length 9: 1198
up to length 10: 2260
up to length 11: 4261
up to length 12: 8029
up to length 13: 15124
up to length 14: 28486
up to length 15: 53650
up to length 16: 101038
up to length 17: 190279
up to length 18: 358339
up to length 19: 674830
up to length 20: 1270846
up to length 21: 2393266
up to length 22: 4507012
up to length 23: 8487625
*/
static double gaussian_sqrt5_real(NUMBER x)
@ -82,9 +86,56 @@ static double gaussian_sqrt5_imag(NUMBER x)
return result;
}
static int read_idlist(const char *filename, int *list)
{
FILE *f = fopen(filename, "r");
if(f == NULL) {
fprintf(stderr, "Could not open %s\n", filename);
exit(1);
}
char *line = NULL;
size_t len = 0;
ssize_t read;
int n = 0;
while ((read = getline(&line, &len, f)) != -1)
list[n++] = atoi(line);
if (line)
free(line);
fclose(f);
return n;
}
static int compare_int(const void *a, const void *b)
{
const int *aa = a;
const int *bb = b;
return (*aa > *bb) - (*aa < *bb);
}
static double runtime()
{
static struct timespec starttime;
static int started = 0;
if(!started) {
clock_gettime(CLOCK_MONOTONIC, &starttime);
started = 1;
}
struct timespec curtime;
double diff;
clock_gettime(CLOCK_MONOTONIC, &curtime);
return (curtime.tv_sec - starttime.tv_sec) + (curtime.tv_nsec - starttime.tv_nsec) / 1e9;
}
enum mode {
MODE_HELP,
MODE_TRACES,
MODE_EIGENVALUES,
MODE_SUMMARY,
MODE_TRACE_IDS
};
@ -94,10 +145,13 @@ int main(int argc, char *argv[])
char buf[100];
int mode;
runtime(); // start timer
// parse arguments
if(argc < 2 || strcmp(argv[1], "help") == 0)
mode = MODE_HELP;
else if(strcmp(argv[1], "traces") == 0)
mode = MODE_TRACES;
else if(strcmp(argv[1], "evs") == 0)
mode = MODE_EIGENVALUES;
else if(strcmp(argv[1], "summary") == 0)
mode = MODE_SUMMARY;
else if(strcmp(argv[1], "trace_ids") == 0)
@ -106,72 +160,78 @@ int main(int argc, char *argv[])
mode = MODE_HELP;
if(mode == MODE_HELP) {
fprintf(stderr, "Usage: %s <help|traces|summary|trace_ids> [arguments]\n", argv[0]);
fprintf(stderr, "Usage: %s <help|evs|summary|trace_ids> [arguments]\n", argv[0]);
fprintf(stderr, "%s help display this page\n", argv[0]);
fprintf(stderr, "%s traces <n> <qreal> <qimag> enumerate group and output unique trace/trace inverse pairs\n", argv[0]);
fprintf(stderr, "%s summary <n> <qreal> <qimag> only output max slope etc.\n", argv[0]);
fprintf(stderr, "%s trace_ids <n> <qreal> <qimag> list of ids of unique traces\n", argv[0]);
fprintf(stderr, "%s evs <n> <q1> <q2> <q3> <treal> <timag> enumerate group and output unique (log) eigenvalue triples\n", argv[0]);
fprintf(stderr, "%s summary <n> <q1> <q2> <q3> <treal> <timag> only output max slope etc.\n", argv[0]);
fprintf(stderr, "%s trace_ids <n> <q1> <q2> <q3> <treal> <timag> list of ids of unique traces\n", argv[0]);
return 0;
}
if(argc < 5) {
if(argc < 8) {
fprintf(stderr, "Not enough arguments!\n");
return 0;
}
int n = atoi(argv[2]);
int nlist, nuniq;
mpq_t qreal, qimag;
mpq_inits(qreal, qimag, NULL);
mpq_set_str(qreal, argv[3], 10);
mpq_set_str(qimag, argv[4], 10);
// mpq_set_si(qreal, 50, 10);
// mpq_set_si(qimag, 1, 10);
mpq_canonicalize(qreal);
mpq_canonicalize(qimag);
/*
int length = 0;
LOOP(i, n) {
if(group->elements[i].length > length) {
printf("Elements up to length %d: %d\n", length, i);
length = group->elements[i].length;
}
}
return 0;
*/
/*
LOOP(i, n) {
groupelement_t *cur = &group->elements[i];
groupelement_t *other;
cur->conjugacy_class = cur; // start with itself and reduce if possible
LOOP(j, 3) {
if(cur->left[j] && cur->left[j]->right[j]) {
other = cur->left[j]->right[j];
if(other->id < cur->id)
cur->conjugacy_class = other->conjugacy_class;
}
if(cur->right[j] && cur->right[j]->left[j]) {
other = cur->right[j]->left[j];
if(other->id < cur->id)
cur->conjugacy_class = other->conjugacy_class;
}
}
}
*/
int q[3];
mpq_t treal, timag;
q[0] = atoi(argv[3]);
q[1] = atoi(argv[4]);
q[2] = atoi(argv[5]);
mpq_inits(treal, timag, NULL);
mpq_set_str(treal, argv[6], 10);
mpq_set_str(timag, argv[7], 10);
mpq_canonicalize(treal);
mpq_canonicalize(timag);
// enumerate group
INFO("generate group\n");
group_t *group = coxeter_init_triangle(5, 5, 5, n);
// read list of elements we need to compute, or just fill it with all elements
INFO("prepare list\n");
int *idlist = malloc(n*sizeof(int));
char *id_file = getenv("IDLIST");
if(id_file != NULL) {
nlist = read_idlist(id_file, idlist);
// sort and symmetrize the list
qsort(idlist, nlist, sizeof(int), compare_int);
int ninverses = 0;
LOOP(i, nlist) {
int id = idlist[i];
int invid = group->elements[id].inverse->id;
if(!bsearch(&invid, idlist, nlist, sizeof(int), compare_int)) {
idlist[nlist+ninverses] = invid;
ninverses++;
}
}
nlist += ninverses;
qsort(idlist, nlist, sizeof(int), compare_int);
} else {
// just list all elements which have inverses
nlist = 0;
LOOP(i, n) {
if(group->elements[i].inverse)
idlist[nlist++] = i;
}
}
// get generator matrices
INFO("make generators\n");
mat gen[3];
LOOP(i, 3) mat_init(gen[i], 3, QT_GAUSS_SQRT5);
generators_triangle_reflection_group_555_complex(gen, 2, 2, 2, qreal, qimag);
generators_triangle_reflection_group_555_complex(gen, q[0], q[1], q[2], treal, timag);
// compute the traces of all elements in idlist
INFO("enumerate traces\n");
struct tracedata *traces;
int nuniq = enumerate_coxeter_group_traces(group, gen, &traces);
nuniq = enumerate_coxeter_group_traces(group, gen, &traces, idlist, nlist, 1);
// compute eigenvalues out of traces
INFO("compute eigenvalues\n");
mps_context *solver = mps_context_new();
mps_monomial_poly *poly = mps_monomial_poly_new(solver, 3);
mps_context_set_output_prec(solver, 20); // relative precision
@ -198,7 +258,14 @@ int main(int argc, char *argv[])
if(fabs(ev_abs2[0]) < fabs(ev_abs2[1]))
SWAP(double, ev_abs2[0], ev_abs2[1]);
if(log(ev_abs2[0]) < 1e-3) // we regard this as a finite order element
if(mode == MODE_TRACE_IDS) {
// we only want to record unordered pairs here
if(CMP(traces[i].tr, traces[i].trinv) >= 0)
printf("%d\n", traces[i].id);
continue;
}
if(log(ev_abs2[0]) < 1e-6) // we regard this as a finite order element
continue;
double slope = - log(ev_abs2[0]) / log(ev_abs2[2]);
@ -207,28 +274,31 @@ int main(int argc, char *argv[])
max_slope_id = traces[i].id;
}
if(mode == MODE_TRACES) {
if(mode == MODE_EIGENVALUES) {
printf("%d %f %f %f\n",
traces[i].id, log(ev_abs2[0]), log(ev_abs2[1]), log(ev_abs2[2]));
} else if(mode == MODE_TRACE_IDS) {
printf("%d\n", traces[i].id);
traces[i].id, log(ev_abs2[0])/2, log(ev_abs2[1])/2, log(ev_abs2[2])/2);
}
}
// output summary
coxeter_snprint(buf, sizeof(buf), &group->elements[max_slope_id]);
if(mode == MODE_SUMMARY) {
gmp_fprintf(stdout, "%f %f %d %d %f %s\n", mpq_get_d(qreal), mpq_get_d(qimag), n, nuniq, max_slope, buf);
} else {
gmp_fprintf(stderr, "q = %Qd + i*%Qd\tElements: %d\tTraces: %d\tMaximal slope: %f at %s\n", qreal, qimag, n, nuniq, max_slope, buf);
gmp_fprintf(stdout, "%f %f %d %d %d %f %s\n", mpq_get_d(treal), mpq_get_d(timag), n, nlist, nuniq, max_slope, buf);
} else if(mode == MODE_EIGENVALUES) {
gmp_fprintf(stderr, "q = %.2f + i*%.2f\tn = %d\tnlist = %d\tnuniq = %d\tMaximal slope: %f at %s\n", mpq_get_d(treal), mpq_get_d(timag), n, nlist, nuniq, max_slope, buf);
} else if(mode == MODE_TRACE_IDS) {
gmp_fprintf(stderr, "q = %.2f + i*%.2f\tElements: %d\tTraces: %d\n", mpq_get_d(treal), mpq_get_d(timag), n, nuniq);
}
mps_monomial_poly_free(solver, MPS_POLYNOMIAL(poly));
// clean up
INFO("clean up\n");
// mps_monomial_poly_free(solver, MPS_POLYNOMIAL(poly));
mps_context_free(solver);
enumerate_tracedata_clear(traces, nuniq);
free(idlist);
LOOP(i, 3) mat_clear(gen[i]);
coxeter_clear(group);
mpq_clears(qreal, qimag, NULL);
mpq_clears(treal, timag, NULL);
return 0;
}

9
compute_picture.sh Executable file
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@ -0,0 +1,9 @@
#!/bin/bash
for i in $(seq -50 50); do
for j in $(seq 0 50); do
if [ $i -ne 0 ] || [ $j -ne 0 ]; then
IDLIST=output/idlist_13 ./complex_anosov summary 15124 1 1 1 $i/50 $j/50
fi
done
done

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@ -3,25 +3,84 @@
#include <stdlib.h>
#define LOOP(i,n) for(int i = 0; i < (n); i++)
// #define INFO(msg, ...) fprintf(stderr, "[%10.3f] " msg, runtime(), ##__VA_ARGS__)
#define INFO(msg, ...)
void enumerate_coxeter_group(group_t *group, mat *gen, mat *matrices)
static int compare_int(const void *a, const void *b)
{
TYPE t = GETTYPE(gen[0]->x[0]);
const int *aa = a;
const int *bb = b;
return (*aa > *bb) - (*aa < *bb);
}
static int index_in_list(const int *list, int n, int key)
{
int *ptr = bsearch(&key, list, n, sizeof(int), compare_int);
if(ptr)
return ptr - list;
else
return -1;
}
// idlist is assumed to be sorted and symmetric
void enumerate_coxeter_group(group_t *group, mat *gen, mat *matrices, const int *idlist, int nlist)
{
TYPE type = GETTYPE(gen[0]->x[0]);
mat_workspace *ws;
ws = mat_workspace_init(3, t);
// mark elements which we need to compute
int ncompute = 0;
LOOP(i, group->size) group->elements[i].need_to_compute = 0;
LOOP(i, nlist) {
groupelement_t *cur = &group->elements[idlist[i]];
while(cur && cur->need_to_compute == 0) {
cur->need_to_compute = 1;
ncompute++;
cur = cur->parent;
}
}
INFO("need to compute %d elements for %d elements in list\n", ncompute, nlist);
mat_identity(matrices[0]);
for(int i = 1; i < group->size; i++) {
if(!group->elements[i].inverse)
continue;
// compute them depth first
int maxlen = group->elements[group->size-1].length;
int parent = group->elements[i].parent->id;
int letter = group->elements[i].letter;
groupelement_t **stack = malloc((maxlen+1)*sizeof(groupelement_t));
int *letter_stack = malloc((maxlen+1)*sizeof(int));
mat *matrix_stack = malloc((maxlen+1)*sizeof(mat));
int level = 0;
mat_multiply(ws, matrices[i], matrices[parent], gen[letter]);
LOOP(i, maxlen+1) mat_init(matrix_stack[i], 3, type);
ws = mat_workspace_init(3, type);
stack[0] = &group->elements[0];
mat_identity(matrix_stack[0]);
letter_stack[0] = 0;
while(level >= 0) {
int letter = letter_stack[level];
groupelement_t *next = stack[level]->left[letter];
if(next && next->length > level && next->need_to_compute) {
mat_multiply(ws, matrix_stack[level+1], gen[letter], matrix_stack[level]);
int id = next->id;
int listid = index_in_list(idlist, nlist, id);
if(listid != -1)
mat_copy(matrices[listid], matrix_stack[level+1]);
next->need_to_compute = 0;
stack[level+1] = next;
letter_stack[level+1] = 0;
level++;
} else {
letter = ++letter_stack[level];
while(letter >= group->rank) { // done with this level, go back down
level--;
if(level < 0)
break;
letter = ++letter_stack[level];
}
}
}
LOOP(i, maxlen+1) mat_clear(matrix_stack[i]);
mat_workspace_clear(ws);
}
@ -48,44 +107,45 @@ static int compare_tracedata_id(const void *a, const void *b)
return ida > idb ? 1 : ida < idb ? -1 : 0;
}
int enumerate_coxeter_group_traces(group_t *group, mat *gen, struct tracedata **traces_out)
int enumerate_coxeter_group_traces(group_t *group, mat *gen, struct tracedata **traces_out, const int *idlist, int nlist, int unique)
{
TYPE t = GETTYPE(gen[0]->x[0]);
int n = group->size;
int nuniq;
mat *matrices = malloc(n*sizeof(mat));
struct tracedata *traces = malloc(n*sizeof(struct tracedata));
struct tracedata **distinct_traces = malloc(n*sizeof(struct tracedata*));
mat *matrices = malloc(nlist*sizeof(mat));
struct tracedata *traces = malloc(nlist*sizeof(struct tracedata));
struct tracedata **distinct_traces = malloc(nlist*sizeof(struct tracedata*));
LOOP(i, n) mat_init(matrices[i], 3, t);
enumerate_coxeter_group(group, gen, matrices);
LOOP(i, nlist) mat_init(matrices[i], 3, t);
enumerate_coxeter_group(group, gen, matrices, idlist, nlist);
LOOP(i, n) {
LOOP(i, nlist) {
INIT(traces[i].tr, t);
INIT(traces[i].trinv, t);
}
LOOP(i, n) {
if(!group->elements[i].inverse)
continue;
int inv_id_in_list = index_in_list(idlist, nlist, group->elements[idlist[i]].inverse->id);
mat_trace(traces[i].tr, matrices[i]);
mat_trace(traces[i].trinv, matrices[group->elements[i].inverse->id]);
traces[i].id = i;
mat_trace(traces[i].trinv, matrices[inv_id_in_list]);
traces[i].id = idlist[i];
distinct_traces[i] = &traces[i];
}
qsort(distinct_traces, n, sizeof(struct tracedata*), compare_tracedata);
if(unique) {
qsort(distinct_traces, nlist, sizeof(struct tracedata*), compare_tracedata);
int nuniq = 0;
LOOP(i, n) {
if(i == 0 || compare_tracedata(&distinct_traces[i], &distinct_traces[nuniq-1]) != 0) {
distinct_traces[nuniq] = distinct_traces[i];
nuniq++;
} else {
int oldlength = group->elements[distinct_traces[nuniq-1]->id].length;
int newlength = group->elements[distinct_traces[i]->id].length;
if(newlength < oldlength)
distinct_traces[nuniq-1]->id = distinct_traces[i]->id;
nuniq = 0;
LOOP(i, nlist) {
if(i == 0 || compare_tracedata(&distinct_traces[i], &distinct_traces[nuniq-1]) != 0) {
distinct_traces[nuniq] = distinct_traces[i];
nuniq++;
} else {
int oldlength = group->elements[distinct_traces[nuniq-1]->id].length;
int newlength = group->elements[distinct_traces[i]->id].length;
if(newlength < oldlength)
distinct_traces[nuniq-1]->id = distinct_traces[i]->id;
}
}
} else {
nuniq = nlist;
}
qsort(distinct_traces, nuniq, sizeof(struct tracedata*), compare_tracedata_id);
@ -99,8 +159,8 @@ int enumerate_coxeter_group_traces(group_t *group, mat *gen, struct tracedata **
unique_traces[i].id = distinct_traces[i]->id;
}
LOOP(i, n) mat_clear(matrices[i]);
LOOP(i, n) {
LOOP(i, nlist) mat_clear(matrices[i]);
LOOP(i, nlist) {
CLEAR(traces[i].tr);
CLEAR(traces[i].trinv);
}

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@ -12,8 +12,8 @@ struct tracedata {
NUMBER trinv;
};
void enumerate_coxeter_group(group_t *group, mat *gen, mat *matrices);
int enumerate_coxeter_group_traces(group_t *group, mat *gen, struct tracedata **traces_out);
void enumerate_coxeter_group(group_t *group, mat *gen, mat *matrices, const int *idlist, int nlist);
int enumerate_coxeter_group_traces(group_t *group, mat *gen, struct tracedata **traces_out, const int *idlist, int nlist, int unique);
void enumerate_tracedata_clear(struct tracedata *traces, int n);

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@ -3,39 +3,39 @@
#define LOOP(i,n) for(int i = 0; i < (n); i++)
void generators_triangle_reflection_generic(mat *gen, NUMBER rho1, NUMBER rho2, NUMBER rho3, NUMBER q)
void generators_triangle_reflection_generic(mat *gen, NUMBER sqrho1, NUMBER sqrho2, NUMBER sqrho3, NUMBER t)
{
NUMBER tmp;
NUMBER qinv;
TYPE t = GETTYPE(rho1);
NUMBER tinv;
TYPE type = GETTYPE(sqrho1);
INIT(tmp, t);
INIT(qinv, t);
INV(qinv, q);
INIT(tmp, type);
INIT(tinv, type);
INV(tinv, t);
LOOP(i, 3) {
mat_init(gen[i], 3, t);
mat_init(gen[i], 3, type);
mat_zero(gen[i]);
LOOP(j, 3) {
SET_INT(*mat_ref(gen[i], j, j), i == j ? 1 : -1);
}
}
MUL(tmp, q, rho1);
MUL(tmp, t, sqrho1);
NEG(*mat_ref(gen[2], 1, 2), tmp);
MUL(tmp, q, rho2);
NEG(*mat_ref(gen[0], 2, 0), tmp);
MUL(tmp, q, rho3);
NEG(*mat_ref(gen[1], 0, 1), tmp);
NEG(*mat_ref(gen[0], 2, 0), sqrho2);
NEG(*mat_ref(gen[1], 0, 1), sqrho3);
NEG(*mat_ref(gen[1], 2, 1), qinv);
NEG(*mat_ref(gen[2], 0, 2), qinv);
NEG(*mat_ref(gen[0], 1, 0), qinv);
MUL(tmp, tinv, sqrho1);
NEG(*mat_ref(gen[1], 2, 1), tmp);
NEG(*mat_ref(gen[2], 0, 2), sqrho2);
NEG(*mat_ref(gen[0], 1, 0), sqrho3);
CLEAR(tmp);
CLEAR(qinv);
CLEAR(tinv);
}
// warning: this is not compatible anymore!
int generators_triangle_reflection_group(mat *gen, int p1, int p2, int p3, int q1, int q2, int q3, mpq_t t)
{
int p[3] = {p1, p2, p3};
@ -107,23 +107,23 @@ int generators_triangle_reflection_group_555_complex(mat *gen, int q1, int q2, i
int q[3] = {q1, q2, q3};
NUMBER rho[3];
LOOP(i, 3) INIT(rho[i], QT_GAUSS_SQRT5);
NUMBER sqrho[3];
LOOP(i, 3) INIT(sqrho[i], QT_GAUSS_SQRT5);
// compute rho1, rho2, rho3
// compute sqrho1, sqrho2, sqrho3
LOOP(i, 3) {
if(q[i] == 1) {
// 4cos(pi/5)^2 = 3/2 + 1/2*sqrt(5)
mpq_set_si(rho[i]->a[0], 3, 2);
mpq_set_si(rho[i]->a[1], 7, 12);
mpq_set_si(rho[i]->a[2], 0, 1);
mpq_set_si(rho[i]->a[3], -1, 24);
// 2cos(pi/5) = 1/2 + 1/2*sqrt(5) = 1/2 + 7/12 a - 1/24 a^3
mpq_set_si(sqrho[i]->a[0], 1, 2);
mpq_set_si(sqrho[i]->a[1], 7, 12);
mpq_set_si(sqrho[i]->a[2], 0, 1);
mpq_set_si(sqrho[i]->a[3], -1, 24);
} else if(q[i] == 2) {
// 4cos(pi/5)^2 = 3/2 - 1/2*sqrt(5)
mpq_set_si(rho[i]->a[0], 3, 2);
mpq_set_si(rho[i]->a[1], -7, 12);
mpq_set_si(rho[i]->a[2], 0, 1);
mpq_set_si(rho[i]->a[3], 1, 24);
// 2cos(pi/5) = -1/2 + 1/2*sqrt(5)
mpq_set_si(sqrho[i]->a[0], -1, 2);
mpq_set_si(sqrho[i]->a[1], 7, 12);
mpq_set_si(sqrho[i]->a[2], 0, 1);
mpq_set_si(sqrho[i]->a[3], -1, 24);
} else {
return 0;
}
@ -138,9 +138,9 @@ int generators_triangle_reflection_group_555_complex(mat *gen, int q1, int q2, i
mpq_set_si(param->a[3], 1, 12);
mpq_mul(param->a[3], param->a[3], timag);
generators_triangle_reflection_generic(gen, rho[0], rho[1], rho[2], param);
generators_triangle_reflection_generic(gen, sqrho[0], sqrho[1], sqrho[2], param);
LOOP(i, 3) CLEAR(rho[i]);
LOOP(i, 3) CLEAR(sqrho[i]);
CLEAR(param);
return 1;

67
make_picture.py Executable file
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@ -0,0 +1,67 @@
#!/usr/bin/python
import sys
import math
def sharpen(x):
alpha = 1
y = abs(2*x-1)**alpha # between 0 and 1
if x > 0.499 and x < 0.501:
return 0.5
elif x > 0.5:
return (y+1)/2
else:
return (1-y)/2
f = open(sys.argv[1])
lines = [x.split() for x in f]
f.close()
res1 = int(sys.argv[2]) # 400 pixel per unit
res2 = int(sys.argv[3]) # 50 pixel in picture (acutally one quadrant)
data = {(round(float(l[0])*res1), round(float(l[1])*res1)) : float(l[5]) for l in lines}
data[(0,0)] = 2.0
print("P3")
print("1000 1000")
print("255")
for i in range (-500,500):
for j in range(-500,500):
x = j/500*res2
y = i/500*res2
if y < 0:
y = -y
x0 = math.floor(x)
y0 = math.floor(y)
x1 = math.ceil(x)
y1 = math.ceil(y)
tx = sharpen(x-x0)
ty = sharpen(y-y0)
if not (x0,y0) in data or not (x0,y1) in data or not (x1,y0) in data or not (x1,y1) in data:
value = 0
else:
value = 0.0
value += data[(x0,y0)]*(1-tx)*(1-ty)
value += data[(x0,y1)]*(1-tx)*ty
value += data[(x1,y0)]*tx*(1-ty)
value += data[(x1,y1)]*tx*ty
value -= 1
value = 0 if value < 0 else 1 if value > 1 else value
r = round(255*math.sqrt(value))
g = round(255*(value)**3)
b = round(255*math.sin(2*math.pi*(value)))
r = 0 if r < 0 else 255 if r > 255 else r
g = 0 if g < 0 else 255 if g > 255 else g
b = 0 if b < 0 else 255 if b > 255 else b
print("%d %d %d" % (r,g,b))
#print(data)