double igraph_norm_rand(void) {
double u1;
#define BIG 134217728 /* 2^27 */
/* unif_rand() alone is not of high enough precision */
u1 = RNG_UNIF(0,1);
u1 = (int)(BIG*u1) + RNG_UNIF(0,1);
return igraph_qnorm5(u1/BIG, 0.0, 1.0, 1, 0);
}
int splicing_simulate_paired_reads(const splicing_gff_t *gff, int gene,
const splicing_vector_t *expression,
int noreads, int readLength,
const splicing_vector_t *fragmentProb,
int fragmentStart, double normalMean,
double normalVar, double numDevs,
splicing_vector_int_t *isoform,
splicing_vector_int_t *position,
splicing_strvector_t *cigar,
splicing_vector_t *sampleprob) {
size_t i, j, noiso, il, nogenes;
splicing_vector_t *mysampleprob=sampleprob, vsampleprob;
splicing_vector_t px, cpx;
double sumpx, sumpsi=0.0;
splicing_vector_int_t isolen;
int goodiso=0;
splicing_vector_int_t exstart, exend, exidx;
splicing_vector_t *myfragmentProb=(splicing_vector_t*) fragmentProb,
vfragmentProb;
int fs, fl;
SPLICING_CHECK(splicing_gff_nogenes(gff, &nogenes));
if (gene < 0 || gene >= nogenes) {
SPLICING_ERROR("Invalid gene id", SPLICING_EINVAL);
}
/* TODO: more error checks */
if (!fragmentProb) {
myfragmentProb=&vfragmentProb;
SPLICING_CHECK(splicing_vector_init(&vfragmentProb, 0));
SPLICING_FINALLY(splicing_vector_destroy, &vfragmentProb);
SPLICING_CHECK(splicing_normal_fragment(normalMean, normalVar, numDevs,
readLength, myfragmentProb,
&fragmentStart));
splicing_vector_scale(myfragmentProb,
1.0/splicing_vector_sum(myfragmentProb));
}
il=splicing_vector_size(myfragmentProb);
fs=fragmentStart;
fl=fragmentStart+il-1;
SPLICING_CHECK(splicing_gff_noiso_one(gff, gene, &noiso));
if ( fabs(splicing_vector_sum(myfragmentProb) - 1.0) > 1e-10 ) {
SPLICING_ERROR("Fragment length distribution does not sum up to 1",
SPLICING_EINVAL);
}
SPLICING_CHECK(splicing_vector_int_init(&isolen, noiso));
SPLICING_FINALLY(splicing_vector_int_destroy, &isolen);
SPLICING_CHECK(splicing_gff_isolength_one(gff, gene, &isolen));
SPLICING_CHECK(splicing_vector_copy(&px, myfragmentProb));
SPLICING_FINALLY(splicing_vector_destroy, &px);
SPLICING_CHECK(splicing_vector_init(&cpx, il));
SPLICING_FINALLY(splicing_vector_destroy, &cpx);
if (!sampleprob) {
mysampleprob=&vsampleprob;
SPLICING_CHECK(splicing_vector_init(mysampleprob, noiso));
SPLICING_FINALLY(splicing_vector_destroy, mysampleprob);
} else {
SPLICING_CHECK(splicing_vector_resize(mysampleprob, noiso));
}
for (sumpx=VECTOR(px)[0], i=1; i<il; i++) {
VECTOR(px)[i] += VECTOR(px)[i-1];
sumpx += VECTOR(px)[i];
}
VECTOR(cpx)[0] = VECTOR(px)[0];
for (i=1; i<il; i++) {
VECTOR(cpx)[i] = VECTOR(cpx)[i-1] + VECTOR(px)[i];
}
for (i=0; i<noiso; i++) {
int ilen=VECTOR(isolen)[i];
int r1= ilen >= fl ? ilen - fl + 1 : 0;
int r2= ilen >= fs ? (ilen >= fl ? fl - fs : ilen - fs + 1) : 0;
/* int r3= fs - 1; */
double sp=0.0;
if (r1 > 0) { sp += r1; }
if (r2 > 0) { sp += VECTOR(cpx)[r2-1]; }
VECTOR(*mysampleprob)[i] = sp * VECTOR(*expression)[i];
if (VECTOR(*mysampleprob)[i] != 0) { goodiso += 1; }
sumpsi += VECTOR(*mysampleprob)[i];
}
if (goodiso == 0) {
SPLICING_ERROR("No isoform is possible", SPLICING_FAILURE);
}
for (i=1; i<noiso; i++) {
VECTOR(*mysampleprob)[i] += VECTOR(*mysampleprob)[i-1];
}
SPLICING_CHECK(splicing_vector_int_resize(isoform, noreads*2));
for (i=0; i<2*noreads; i+=2) {
int w;
double rand;
if (noiso==1) {
w=0;
} else if (noiso==2) {
rand = RNG_UNIF01() * sumpsi;
w = (rand < VECTOR(*mysampleprob)[0]) ? 0 : 1;
} else {
rand = RNG_UNIF01() * sumpsi;
for (w=0; rand > VECTOR(*mysampleprob)[w]; w++) ;
}
VECTOR(*isoform)[i]=VECTOR(*isoform)[i+1]=w;
}
if (!sampleprob) {
splicing_vector_destroy(mysampleprob);
SPLICING_FINALLY_CLEAN(1);
} else {
for (i=noiso-1; i>0; i--) {
VECTOR(*mysampleprob)[i] -= VECTOR(*mysampleprob)[i-1];
}
}
/* We have the isoforms, now get the read positions. */
SPLICING_CHECK(splicing_vector_int_resize(position, noreads*2));
SPLICING_CHECK(splicing_vector_int_init(&exstart, 0));
SPLICING_FINALLY(splicing_vector_int_destroy, &exstart);
SPLICING_CHECK(splicing_vector_int_init(&exend, 0));
SPLICING_FINALLY(splicing_vector_int_destroy, &exend);
SPLICING_CHECK(splicing_vector_int_init(&exidx, 0));
SPLICING_FINALLY(splicing_vector_int_destroy, &exidx);
SPLICING_CHECK(splicing_gff_exon_start_end(gff, &exstart, &exend, &exidx,
gene));
/* Positions in isoform coordinates first.
These are sampled based on the fragment length distribution. */
for (i=0, j=0; i<noreads; i++) {
int iso=VECTOR(*isoform)[2*i];
int ilen=VECTOR(isolen)[iso];
int r1= ilen >= fl ? ilen - fl + 1 : 0;
int r2= ilen >= fs ? (ilen >= fl ? fl - fs : ilen - fs + 1) : 0;
/* int r3= fs - 1; */
int pos, fragment;
double sp=0.0;
if (r1 > 0) { sp += r1; }
if (r2 > 0) { sp += VECTOR(cpx)[r2-1]; }
double rand=RNG_UNIF(0, sp);
if (rand < r1) {
pos = ceil(rand);
} else {
int w;
rand -= r1;
for (w=0; VECTOR(cpx)[w] < rand; w++) ;
pos = r1 + r2 - w;
}
if (pos <= r1) {
rand=RNG_UNIF(0, 1.0);
} else {
rand=RNG_UNIF(0, VECTOR(px)[r1+r2-pos]);
}
for (fragment=0; VECTOR(px)[fragment] < rand; fragment++) ;
fragment += fragmentStart;
VECTOR(*position)[j++] = pos;
VECTOR(*position)[j++] = pos+fragment-readLength;
}
/* Translate positions to genomic coordinates */
/* TODO: some of this is already calculated */
SPLICING_CHECK(splicing_iso_to_genomic(gff, gene, isoform, /*converter=*/ 0,
position));
/* CIGAR strings */
splicing_strvector_clear(cigar);
SPLICING_CHECK(splicing_strvector_reserve(cigar, 2*noreads));
for (j=0; j<2*noreads; j++) {
char tmp[1000], *tmp2=tmp;
int iso=VECTOR(*isoform)[j];
size_t rs=VECTOR(*position)[j];
int ex=0;
int rl=readLength;
for (ex=VECTOR(exidx)[iso]; VECTOR(exend)[ex] < rs; ex++) ;
while (rs + rl - 1 > VECTOR(exend)[ex]) {
tmp2 += snprintf(tmp2, sizeof(tmp)/sizeof(char)-(tmp2-tmp)-1, "%iM%iN",
(int) (VECTOR(exend)[ex]-rs+1),
(int) (VECTOR(exstart)[ex+1]-VECTOR(exend)[ex]-1));
if (tmp2 >= tmp + sizeof(tmp)/sizeof(char)) {
SPLICING_ERROR("CIGAR string too long", SPLICING_EINVAL);
}
rl -= (VECTOR(exend)[ex] - rs + 1);
rs = VECTOR(exstart)[ex+1];
ex++;
}
tmp2 += snprintf(tmp2, sizeof(tmp)/sizeof(char)-(tmp2-tmp)-1, "%iM", rl);
if (tmp2 >= tmp + sizeof(tmp)/sizeof(char)) {
SPLICING_ERROR("CIGAR string too long", SPLICING_EINVAL);
}
SPLICING_CHECK(splicing_strvector_append(cigar, tmp));
}
splicing_vector_int_destroy(&exidx);
splicing_vector_int_destroy(&exend);
splicing_vector_int_destroy(&exstart);
splicing_vector_destroy(&cpx);
splicing_vector_destroy(&px);
splicing_vector_int_destroy(&isolen);
SPLICING_FINALLY_CLEAN(6);
if (!fragmentProb) {
splicing_vector_destroy(myfragmentProb);
SPLICING_FINALLY_CLEAN(1);
}
return 0;
}
int igraph_layout_gem(const igraph_t *graph, igraph_matrix_t *res,
igraph_bool_t use_seed, igraph_integer_t maxiter,
igraph_real_t temp_max, igraph_real_t temp_min,
igraph_real_t temp_init) {
igraph_integer_t no_nodes = igraph_vcount(graph);
igraph_vector_int_t perm;
igraph_vector_float_t impulse_x, impulse_y, temp, skew_gauge;
igraph_integer_t i;
float temp_global;
igraph_integer_t perm_pointer = 0;
float barycenter_x = 0.0, barycenter_y = 0.0;
igraph_vector_t phi;
igraph_vector_t neis;
const float elen_des2 = 128 * 128;
const float gamma = 1/16.0;
const float alpha_o = M_PI;
const float alpha_r = M_PI / 3.0;
const float sigma_o = 1.0 / 3.0;
const float sigma_r = 1.0 / 2.0 / no_nodes;
if (maxiter < 0) {
IGRAPH_ERROR("Number of iterations must be non-negative in GEM layout",
IGRAPH_EINVAL);
}
if (use_seed && (igraph_matrix_nrow(res) != no_nodes ||
igraph_matrix_ncol(res) != 2)) {
IGRAPH_ERROR("Invalid start position matrix size in GEM layout",
IGRAPH_EINVAL);
}
if (temp_max <= 0) {
IGRAPH_ERROR("Maximum temperature should be positive in GEM layout",
IGRAPH_EINVAL);
}
if (temp_min <= 0) {
IGRAPH_ERROR("Minimum temperature should be positive in GEM layout",
IGRAPH_EINVAL);
}
if (temp_init <= 0) {
IGRAPH_ERROR("Initial temperature should be positive in GEM layout",
IGRAPH_EINVAL);
}
if (temp_max < temp_init || temp_init < temp_min) {
IGRAPH_ERROR("Minimum <= Initial <= Maximum temperature is required "
"in GEM layout", IGRAPH_EINVAL);
}
if (no_nodes == 0) { return 0; }
IGRAPH_CHECK(igraph_vector_float_init(&impulse_x, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &impulse_x);
IGRAPH_CHECK(igraph_vector_float_init(&impulse_y, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &impulse_y);
IGRAPH_CHECK(igraph_vector_float_init(&temp, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &temp);
IGRAPH_CHECK(igraph_vector_float_init(&skew_gauge, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &skew_gauge);
IGRAPH_CHECK(igraph_vector_int_init_seq(&perm, 0, no_nodes-1));
IGRAPH_FINALLY(igraph_vector_int_destroy, &perm);
IGRAPH_VECTOR_INIT_FINALLY(&phi, no_nodes);
IGRAPH_VECTOR_INIT_FINALLY(&neis, 10);
RNG_BEGIN();
/* Initialization */
igraph_degree(graph, &phi, igraph_vss_all(), IGRAPH_ALL, IGRAPH_LOOPS);
if (!use_seed) {
const igraph_real_t width_half=no_nodes*100, height_half=width_half;
IGRAPH_CHECK(igraph_matrix_resize(res, no_nodes, 2));
for (i=0; i<no_nodes; i++) {
MATRIX(*res, i, 0) = RNG_UNIF(-width_half, width_half);
MATRIX(*res, i, 1) = RNG_UNIF(-height_half, height_half);
barycenter_x += MATRIX(*res, i, 0);
barycenter_y += MATRIX(*res, i, 1);
VECTOR(phi)[i] *= (VECTOR(phi)[i] / 2.0 + 1.0);
}
} else {
for (i=0; i<no_nodes; i++) {
barycenter_x += MATRIX(*res, i, 0);
barycenter_y += MATRIX(*res, i, 1);
VECTOR(phi)[i] *= (VECTOR(phi)[i] / 2.0 + 1.0);
}
}
igraph_vector_float_fill(&temp, temp_init);
temp_global = temp_init * no_nodes;
while (temp_global > temp_min * no_nodes && maxiter > 0) {
/* choose a vertex v to update */
igraph_integer_t u, v, nlen, j;
float px, py, pvx, pvy;
if (!perm_pointer) {
igraph_vector_int_shuffle(&perm);
perm_pointer=no_nodes-1;
}
v=VECTOR(perm)[perm_pointer--];
/* compute v's impulse */
px = (barycenter_x/no_nodes - MATRIX(*res, v, 0)) * gamma * VECTOR(phi)[v];
py = (barycenter_y/no_nodes - MATRIX(*res, v, 1)) * gamma * VECTOR(phi)[v];
px += RNG_UNIF(-32.0, 32.0);
py += RNG_UNIF(-32.0, 32.0);
for (u = 0; u < no_nodes; u++) {
float dx, dy, dist2;
if (u == v) { continue; }
dx=MATRIX(*res, v, 0) - MATRIX(*res, u, 0);
dy=MATRIX(*res, v, 1) - MATRIX(*res, u, 1);
dist2=dx * dx + dy * dy;
if (dist2 != 0) {
px += dx * elen_des2 / dist2;
py += dy * elen_des2 / dist2;
}
}
IGRAPH_CHECK(igraph_neighbors(graph, &neis, v, IGRAPH_ALL));
nlen=igraph_vector_size(&neis);
for (j = 0; j < nlen; j++) {
igraph_integer_t u=VECTOR(neis)[j];
float dx=MATRIX(*res, v, 0) - MATRIX(*res, u, 0);
float dy=MATRIX(*res, v, 1) - MATRIX(*res, u, 1);
float dist2= dx * dx + dy * dy;
px -= dx * dist2 / (elen_des2 * VECTOR(phi)[v]);
py -= dy * dist2 / (elen_des2 * VECTOR(phi)[v]);
}
/* update v's position and temperature */
if (px != 0 || py != 0) {
float plen = sqrtf(px * px + py * py);
px *= VECTOR(temp)[v] / plen;
py *= VECTOR(temp)[v] / plen;
MATRIX(*res, v, 0) += px;
MATRIX(*res, v, 1) += py;
barycenter_x += px;
barycenter_y += py;
}
pvx=VECTOR(impulse_x)[v]; pvy=VECTOR(impulse_y)[v];
if (pvx != 0 || pvy != 0) {
float beta = atan2f(pvy - py, pvx - px);
float sin_beta = sinf(beta);
float sign_sin_beta = (sin_beta > 0) ? 1 : ((sin_beta < 0) ? -1 : 0);
float cos_beta = cosf(beta);
float abs_cos_beta = fabsf(cos_beta);
float old_temp=VECTOR(temp)[v];
if (sin(beta) >= sin(M_PI_2 + alpha_r / 2.0)) {
VECTOR(skew_gauge)[v] += sigma_r * sign_sin_beta;
}
if (abs_cos_beta >= cosf(alpha_o / 2.0)) {
VECTOR(temp)[v] *= sigma_o * cos_beta;
}
VECTOR(temp)[v] *= (1 - fabsf(VECTOR(skew_gauge)[v]));
if (VECTOR(temp)[v] > temp_max) { VECTOR(temp)[v] = temp_max; }
VECTOR(impulse_x)[v] = px;
VECTOR(impulse_y)[v] = py;
temp_global += VECTOR(temp)[v] - old_temp;
}
maxiter--;
} /* while temp && iter */
RNG_END();
igraph_vector_destroy(&neis);
igraph_vector_destroy(&phi);
igraph_vector_int_destroy(&perm);
igraph_vector_float_destroy(&skew_gauge);
igraph_vector_float_destroy(&temp);
igraph_vector_float_destroy(&impulse_y);
igraph_vector_float_destroy(&impulse_x);
IGRAPH_FINALLY_CLEAN(7);
return 0;
}
int igraph_layout_fruchterman_reingold_3d(const igraph_t *graph,
igraph_matrix_t *res,
igraph_bool_t use_seed,
igraph_integer_t niter,
igraph_real_t start_temp,
const igraph_vector_t *weight,
const igraph_vector_t *minx,
const igraph_vector_t *maxx,
const igraph_vector_t *miny,
const igraph_vector_t *maxy,
const igraph_vector_t *minz,
const igraph_vector_t *maxz) {
igraph_integer_t no_nodes=igraph_vcount(graph);
igraph_integer_t no_edges=igraph_ecount(graph);
igraph_integer_t i;
igraph_vector_float_t dispx, dispy, dispz;
igraph_real_t temp=start_temp;
igraph_real_t difftemp=start_temp / niter;
float width=sqrtf(no_nodes), height=width, depth=width;
igraph_bool_t conn=1;
float C;
if (niter < 0) {
IGRAPH_ERROR("Number of iterations must be non-negative in "
"Fruchterman-Reingold layout", IGRAPH_EINVAL);
}
if (use_seed && (igraph_matrix_nrow(res) != no_nodes ||
igraph_matrix_ncol(res) != 3)) {
IGRAPH_ERROR("Invalid start position matrix size in "
"Fruchterman-Reingold layout", IGRAPH_EINVAL);
}
if (weight && igraph_vector_size(weight) != igraph_ecount(graph)) {
IGRAPH_ERROR("Invalid weight vector length", IGRAPH_EINVAL);
}
if (minx && igraph_vector_size(minx) != no_nodes) {
IGRAPH_ERROR("Invalid minx vector length", IGRAPH_EINVAL);
}
if (maxx && igraph_vector_size(maxx) != no_nodes) {
IGRAPH_ERROR("Invalid maxx vector length", IGRAPH_EINVAL);
}
if (minx && maxx && !igraph_vector_all_le(minx, maxx)) {
IGRAPH_ERROR("minx must not be greater than maxx", IGRAPH_EINVAL);
}
if (miny && igraph_vector_size(miny) != no_nodes) {
IGRAPH_ERROR("Invalid miny vector length", IGRAPH_EINVAL);
}
if (maxy && igraph_vector_size(maxy) != no_nodes) {
IGRAPH_ERROR("Invalid maxy vector length", IGRAPH_EINVAL);
}
if (miny && maxy && !igraph_vector_all_le(miny, maxy)) {
IGRAPH_ERROR("miny must not be greater than maxy", IGRAPH_EINVAL);
}
if (minz && igraph_vector_size(minz) != no_nodes) {
IGRAPH_ERROR("Invalid minz vector length", IGRAPH_EINVAL);
}
if (maxz && igraph_vector_size(maxz) != no_nodes) {
IGRAPH_ERROR("Invalid maxz vector length", IGRAPH_EINVAL);
}
if (minz && maxz && !igraph_vector_all_le(minz, maxz)) {
IGRAPH_ERROR("minz must not be greater than maxz", IGRAPH_EINVAL);
}
igraph_is_connected(graph, &conn, IGRAPH_WEAK);
if (!conn) { C = no_nodes * sqrtf(no_nodes); }
RNG_BEGIN();
if (!use_seed) {
IGRAPH_CHECK(igraph_matrix_resize(res, no_nodes, 3));
for (i=0; i<no_nodes; i++) {
igraph_real_t x1=minx ? VECTOR(*minx)[i] : -width/2;
igraph_real_t x2=maxx ? VECTOR(*maxx)[i] : width/2;
igraph_real_t y1=miny ? VECTOR(*miny)[i] : -height/2;
igraph_real_t y2=maxy ? VECTOR(*maxy)[i] : height/2;
igraph_real_t z1=minz ? VECTOR(*minz)[i] : -depth/2;
igraph_real_t z2=maxz ? VECTOR(*maxz)[i] : depth/2;
MATRIX(*res, i, 0) = RNG_UNIF(x1, x2);
MATRIX(*res, i, 1) = RNG_UNIF(y1, y2);
MATRIX(*res, i, 2) = RNG_UNIF(z1, z2);
}
}
IGRAPH_CHECK(igraph_vector_float_init(&dispx, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &dispx);
IGRAPH_CHECK(igraph_vector_float_init(&dispy, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &dispy);
IGRAPH_CHECK(igraph_vector_float_init(&dispz, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &dispz);
for (i=0; i<niter; i++) {
igraph_integer_t v, u, e;
/* calculate repulsive forces, we have a special version
for unconnected graphs */
igraph_vector_float_null(&dispx);
igraph_vector_float_null(&dispy);
igraph_vector_float_null(&dispz);
if (conn) {
for (v=0; v<no_nodes; v++) {
for (u=v+1; u<no_nodes; u++) {
float dx=MATRIX(*res, v, 0) - MATRIX(*res, u, 0);
float dy=MATRIX(*res, v, 1) - MATRIX(*res, u, 1);
float dz=MATRIX(*res, v, 2) - MATRIX(*res, u, 2);
float dlen=dx * dx + dy * dy + dz * dz;
if (dlen == 0) {
dx = RNG_UNIF01() * 1e-9;
dy = RNG_UNIF01() * 1e-9;
dz = RNG_UNIF01() * 1e-9;
dlen = dx * dx + dy * dy + dz * dz;
}
VECTOR(dispx)[v] += dx/dlen;
VECTOR(dispy)[v] += dy/dlen;
VECTOR(dispz)[v] += dz/dlen;
VECTOR(dispx)[u] -= dx/dlen;
VECTOR(dispy)[u] -= dy/dlen;
VECTOR(dispz)[u] -= dz/dlen;
}
}
} else {
for (v=0; v<no_nodes; v++) {
for (u=v+1; u<no_nodes; u++) {
float dx=MATRIX(*res, v, 0) - MATRIX(*res, u, 0);
float dy=MATRIX(*res, v, 1) - MATRIX(*res, u, 1);
float dz=MATRIX(*res, v, 2) - MATRIX(*res, u, 2);
float dlen, rdlen;
dlen=dx * dx + dy * dy + dz * dz;
if (dlen == 0) {
dx = RNG_UNIF01() * 1e-9;
dy = RNG_UNIF01() * 1e-9;
dz = RNG_UNIF01() * 1e-9;
dlen = dx * dx + dy * dy + dz * dz;
}
rdlen=sqrt(dlen);
VECTOR(dispx)[v] += dx * (C-dlen * rdlen) / (dlen*C);
VECTOR(dispy)[v] += dy * (C-dlen * rdlen) / (dlen*C);
VECTOR(dispy)[v] += dz * (C-dlen * rdlen) / (dlen*C);
VECTOR(dispx)[u] -= dx * (C-dlen * rdlen) / (dlen*C);
VECTOR(dispy)[u] -= dy * (C-dlen * rdlen) / (dlen*C);
VECTOR(dispz)[u] -= dz * (C-dlen * rdlen) / (dlen*C);
}
}
}
/* calculate attractive forces */
for (e=0; e<no_edges; e++) {
/* each edges is an ordered pair of vertices v and u */
igraph_integer_t v=IGRAPH_FROM(graph, e);
igraph_integer_t u=IGRAPH_TO(graph, e);
igraph_real_t dx=MATRIX(*res, v, 0) - MATRIX(*res, u, 0);
igraph_real_t dy=MATRIX(*res, v, 1) - MATRIX(*res, u, 1);
igraph_real_t dz=MATRIX(*res, v, 2) - MATRIX(*res, u, 2);
igraph_real_t w=weight ? VECTOR(*weight)[e] : 1.0;
igraph_real_t dlen=sqrt(dx * dx + dy * dy + dz * dz) * w;
VECTOR(dispx)[v] -= (dx * dlen);
VECTOR(dispy)[v] -= (dy * dlen);
VECTOR(dispz)[v] -= (dz * dlen);
VECTOR(dispx)[u] += (dx * dlen);
VECTOR(dispy)[u] += (dy * dlen);
VECTOR(dispz)[u] += (dz * dlen);
}
/* limit max displacement to temperature t and prevent from
displacement outside frame */
for (v=0; v<no_nodes; v++) {
igraph_real_t dx=VECTOR(dispx)[v] + RNG_UNIF01() * 1e-9;
igraph_real_t dy=VECTOR(dispy)[v] + RNG_UNIF01() * 1e-9;
igraph_real_t dz=VECTOR(dispz)[v] + RNG_UNIF01() * 1e-9;
igraph_real_t displen=sqrt(dx * dx + dy * dy + dz * dz);
igraph_real_t mx=fabs(dx) < temp ? dx : temp;
igraph_real_t my=fabs(dy) < temp ? dy : temp;
igraph_real_t mz=fabs(dz) < temp ? dz : temp;
if (displen > 0) {
MATRIX(*res, v, 0) += (dx / displen) * mx;
MATRIX(*res, v, 1) += (dy / displen) * my;
MATRIX(*res, v, 2) += (dz / displen) * mz;
}
if (minx && MATRIX(*res, v, 0) < VECTOR(*minx)[v]) {
MATRIX(*res, v, 0) = VECTOR(*minx)[v];
}
if (maxx && MATRIX(*res, v, 0) > VECTOR(*maxx)[v]) {
MATRIX(*res, v, 0) = VECTOR(*maxx)[v];
}
if (miny && MATRIX(*res, v, 1) < VECTOR(*miny)[v]) {
MATRIX(*res, v, 1) = VECTOR(*miny)[v];
}
if (maxy && MATRIX(*res, v, 1) > VECTOR(*maxy)[v]) {
MATRIX(*res, v, 1) = VECTOR(*maxy)[v];
}
if (minz && MATRIX(*res, v, 2) < VECTOR(*minz)[v]) {
MATRIX(*res, v, 2) = VECTOR(*minz)[v];
}
if (maxz && MATRIX(*res, v, 2) > VECTOR(*maxz)[v]) {
MATRIX(*res, v, 2) = VECTOR(*maxz)[v];
}
}
temp -= difftemp;
}
RNG_END();
igraph_vector_float_destroy(&dispx);
igraph_vector_float_destroy(&dispy);
igraph_vector_float_destroy(&dispz);
IGRAPH_FINALLY_CLEAN(3);
return 0;
}
int igraph_layout_i_fr(const igraph_t *graph,
igraph_matrix_t *res,
igraph_bool_t use_seed,
igraph_integer_t niter,
igraph_real_t start_temp,
const igraph_vector_t *weight,
const igraph_vector_t *minx,
const igraph_vector_t *maxx,
const igraph_vector_t *miny,
const igraph_vector_t *maxy) {
igraph_integer_t no_nodes=igraph_vcount(graph);
igraph_integer_t no_edges=igraph_ecount(graph);
igraph_integer_t i;
igraph_vector_float_t dispx, dispy;
igraph_real_t temp=start_temp;
igraph_real_t difftemp=start_temp / niter;
float width=sqrtf(no_nodes), height=width;
igraph_bool_t conn=1;
float C;
igraph_is_connected(graph, &conn, IGRAPH_WEAK);
if (!conn) { C = no_nodes * sqrtf(no_nodes); }
RNG_BEGIN();
if (!use_seed) {
IGRAPH_CHECK(igraph_matrix_resize(res, no_nodes, 2));
for (i=0; i<no_nodes; i++) {
igraph_real_t x1=minx ? VECTOR(*minx)[i] : -width/2;
igraph_real_t x2=maxx ? VECTOR(*maxx)[i] : width/2;
igraph_real_t y1=miny ? VECTOR(*miny)[i] : -height/2;
igraph_real_t y2=maxy ? VECTOR(*maxy)[i] : height/2;
if (!igraph_finite(x1)) { x1 = -sqrt(no_nodes)/2; }
if (!igraph_finite(x2)) { x2 = sqrt(no_nodes)/2; }
if (!igraph_finite(y1)) { y1 = -sqrt(no_nodes)/2; }
if (!igraph_finite(y2)) { y2 = sqrt(no_nodes)/2; }
MATRIX(*res, i, 0) = RNG_UNIF(x1, x2);
MATRIX(*res, i, 1) = RNG_UNIF(y1, y2);
}
}
IGRAPH_CHECK(igraph_vector_float_init(&dispx, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &dispx);
IGRAPH_CHECK(igraph_vector_float_init(&dispy, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &dispy);
for (i=0; i<niter; i++) {
igraph_integer_t v, u, e;
/* calculate repulsive forces, we have a special version
for unconnected graphs */
igraph_vector_float_null(&dispx);
igraph_vector_float_null(&dispy);
if (conn) {
for (v=0; v<no_nodes; v++) {
for (u=v+1; u<no_nodes; u++) {
float dx=MATRIX(*res, v, 0) - MATRIX(*res, u, 0);
float dy=MATRIX(*res, v, 1) - MATRIX(*res, u, 1);
float dlen=dx * dx + dy * dy;
if (dlen == 0) {
dx = RNG_UNIF01() * 1e-9;
dy = RNG_UNIF01() * 1e-9;
dlen = dx * dx + dy * dy;
}
VECTOR(dispx)[v] += dx/dlen;
VECTOR(dispy)[v] += dy/dlen;
VECTOR(dispx)[u] -= dx/dlen;
VECTOR(dispy)[u] -= dy/dlen;
}
}
} else {
for (v=0; v<no_nodes; v++) {
for (u=v+1; u<no_nodes; u++) {
float dx=MATRIX(*res, v, 0) - MATRIX(*res, u, 0);
float dy=MATRIX(*res, v, 1) - MATRIX(*res, u, 1);
float dlen, rdlen;
dlen=dx * dx + dy * dy;
if (dlen == 0) {
dx = RNG_UNIF(0, 1e-6);
dy = RNG_UNIF(0, 1e-6);
dlen = dx * dx + dy * dy;
}
rdlen=sqrt(dlen);
VECTOR(dispx)[v] += dx * (C-dlen * rdlen) / (dlen*C);
VECTOR(dispy)[v] += dy * (C-dlen * rdlen) / (dlen*C);
VECTOR(dispx)[u] -= dx * (C-dlen * rdlen) / (dlen*C);
VECTOR(dispy)[u] -= dy * (C-dlen * rdlen) / (dlen*C);
}
}
}
/* calculate attractive forces */
for (e=0; e<no_edges; e++) {
/* each edges is an ordered pair of vertices v and u */
igraph_integer_t v=IGRAPH_FROM(graph, e);
igraph_integer_t u=IGRAPH_TO(graph, e);
igraph_real_t dx=MATRIX(*res, v, 0) - MATRIX(*res, u, 0);
igraph_real_t dy=MATRIX(*res, v, 1) - MATRIX(*res, u, 1);
igraph_real_t w=weight ? VECTOR(*weight)[e] : 1.0;
igraph_real_t dlen=sqrt(dx * dx + dy * dy) * w;
VECTOR(dispx)[v] -= (dx * dlen);
VECTOR(dispy)[v] -= (dy * dlen);
VECTOR(dispx)[u] += (dx * dlen);
VECTOR(dispy)[u] += (dy * dlen);
}
/* limit max displacement to temperature t and prevent from
displacement outside frame */
for (v=0; v<no_nodes; v++) {
igraph_real_t dx=VECTOR(dispx)[v] + RNG_UNIF01() * 1e-9;
igraph_real_t dy=VECTOR(dispy)[v] + RNG_UNIF01() * 1e-9;
igraph_real_t displen=sqrt(dx * dx + dy * dy);
igraph_real_t mx=fabs(dx) < temp ? dx : temp;
igraph_real_t my=fabs(dy) < temp ? dy : temp;
if (displen > 0) {
MATRIX(*res, v, 0) += (dx / displen) * mx;
MATRIX(*res, v, 1) += (dy / displen) * my;
}
if (minx && MATRIX(*res, v, 0) < VECTOR(*minx)[v]) {
MATRIX(*res, v, 0) = VECTOR(*minx)[v];
}
if (maxx && MATRIX(*res, v, 0) > VECTOR(*maxx)[v]) {
MATRIX(*res, v, 0) = VECTOR(*maxx)[v];
}
if (miny && MATRIX(*res, v, 1) < VECTOR(*miny)[v]) {
MATRIX(*res, v, 1) = VECTOR(*miny)[v];
}
if (maxy && MATRIX(*res, v, 1) > VECTOR(*maxy)[v]) {
MATRIX(*res, v, 1) = VECTOR(*maxy)[v];
}
}
temp -= difftemp;
}
RNG_END();
igraph_vector_float_destroy(&dispx);
igraph_vector_float_destroy(&dispy);
IGRAPH_FINALLY_CLEAN(2);
return 0;
}
int igraph_layout_i_grid_fr(const igraph_t *graph,
igraph_matrix_t *res, igraph_bool_t use_seed,
igraph_integer_t niter, igraph_real_t start_temp,
const igraph_vector_t *weight, const igraph_vector_t *minx,
const igraph_vector_t *maxx, const igraph_vector_t *miny,
const igraph_vector_t *maxy) {
igraph_integer_t no_nodes=igraph_vcount(graph);
igraph_integer_t no_edges=igraph_ecount(graph);
float width=sqrtf(no_nodes), height=width;
igraph_2dgrid_t grid;
igraph_vector_float_t dispx, dispy;
igraph_real_t temp=start_temp;
igraph_real_t difftemp=start_temp / niter;
igraph_2dgrid_iterator_t vidit;
igraph_integer_t i;
const float cellsize=2.0;
RNG_BEGIN();
if (!use_seed) {
IGRAPH_CHECK(igraph_matrix_resize(res, no_nodes, 2));
for (i=0; i<no_nodes; i++) {
igraph_real_t x1=minx ? VECTOR(*minx)[i] : -width/2;
igraph_real_t x2=maxx ? VECTOR(*maxx)[i] : width/2;
igraph_real_t y1=miny ? VECTOR(*miny)[i] : -height/2;
igraph_real_t y2=maxy ? VECTOR(*maxy)[i] : height/2;
if (!igraph_finite(x1)) { x1 = -sqrt(no_nodes)/2; }
if (!igraph_finite(x2)) { x2 = sqrt(no_nodes)/2; }
if (!igraph_finite(y1)) { y1 = -sqrt(no_nodes)/2; }
if (!igraph_finite(y2)) { y2 = sqrt(no_nodes)/2; }
MATRIX(*res, i, 0) = RNG_UNIF(x1, x2);
MATRIX(*res, i, 1) = RNG_UNIF(y1, y2);
}
}
/* make grid */
IGRAPH_CHECK(igraph_2dgrid_init(&grid, res, -width/2, width/2, cellsize,
-height/2, height/2, cellsize));
IGRAPH_FINALLY(igraph_2dgrid_destroy, &grid);
/* place vertices on grid */
for (i=0; i<no_nodes; i++) {
igraph_2dgrid_add2(&grid, i);
}
IGRAPH_CHECK(igraph_vector_float_init(&dispx, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &dispx);
IGRAPH_CHECK(igraph_vector_float_init(&dispy, no_nodes));
IGRAPH_FINALLY(igraph_vector_float_destroy, &dispy);
for (i=0; i<niter; i++) {
igraph_integer_t v, u, e;
igraph_vector_float_null(&dispx);
igraph_vector_float_null(&dispy);
/* repulsion */
igraph_2dgrid_reset(&grid, &vidit);
while ( (v=igraph_2dgrid_next(&grid, &vidit)-1) != -1) {
while ( (u=igraph_2dgrid_next_nei(&grid, &vidit)-1) != -1) {
float dx=MATRIX(*res, v, 0)-MATRIX(*res, u, 0);
float dy=MATRIX(*res, v, 1)-MATRIX(*res, u, 1);
float dlen=dx * dx + dy * dy;
if (dlen < cellsize * cellsize) {
VECTOR(dispx)[v] += dx/dlen;
VECTOR(dispy)[v] += dy/dlen;
VECTOR(dispx)[u] -= dx/dlen;
VECTOR(dispy)[u] -= dy/dlen;
}
}
}
/* attraction */
for (e=0; e<no_edges; e++) {
igraph_integer_t v=IGRAPH_FROM(graph, e);
igraph_integer_t u=IGRAPH_TO(graph, e);
igraph_real_t dx=MATRIX(*res, v, 0) - MATRIX(*res, u, 0);
igraph_real_t dy=MATRIX(*res, v, 1) - MATRIX(*res, u, 1);
igraph_real_t w=weight ? VECTOR(*weight)[e] : 1.0;
igraph_real_t dlen=sqrt(dx * dx + dy * dy) * w;
VECTOR(dispx)[v] -= (dx * dlen);
VECTOR(dispy)[v] -= (dy * dlen);
VECTOR(dispx)[u] += (dx * dlen);
VECTOR(dispy)[u] += (dy * dlen);
}
/* update */
for (v=0; v<no_nodes; v++) {
igraph_real_t dx=VECTOR(dispx)[v] + RNG_UNIF01() * 1e-9;
igraph_real_t dy=VECTOR(dispy)[v] + RNG_UNIF01() * 1e-9;
igraph_real_t displen=sqrt(dx * dx + dy * dy);
igraph_real_t mx=fabs(dx) < temp ? dx : temp;
igraph_real_t my=fabs(dy) < temp ? dy : temp;
if (displen > 0) {
MATRIX(*res, v, 0) += (dx / displen) * mx;
MATRIX(*res, v, 1) += (dy / displen) * my;
}
if (minx && MATRIX(*res, v, 0) < VECTOR(*minx)[v]) {
MATRIX(*res, v, 0) = VECTOR(*minx)[v];
}
if (maxx && MATRIX(*res, v, 0) > VECTOR(*maxx)[v]) {
MATRIX(*res, v, 0) = VECTOR(*maxx)[v];
}
if (miny && MATRIX(*res, v, 1) < VECTOR(*miny)[v]) {
MATRIX(*res, v, 1) = VECTOR(*miny)[v];
}
if (maxy && MATRIX(*res, v, 1) > VECTOR(*maxy)[v]) {
MATRIX(*res, v, 1) = VECTOR(*maxy)[v];
}
}
temp -= difftemp;
}
igraph_vector_float_destroy(&dispx);
igraph_vector_float_destroy(&dispy);
igraph_2dgrid_destroy(&grid);
IGRAPH_FINALLY_CLEAN(3);
return 0;
}
int igraph_layout_kamada_kawai(const igraph_t *graph, igraph_matrix_t *res,
igraph_bool_t use_seed, igraph_integer_t maxiter,
igraph_real_t epsilon, igraph_real_t kkconst,
const igraph_vector_t *weights,
const igraph_vector_t *minx, const igraph_vector_t *maxx,
const igraph_vector_t *miny, const igraph_vector_t *maxy) {
igraph_integer_t no_nodes=igraph_vcount(graph);
igraph_integer_t no_edges=igraph_ecount(graph);
igraph_real_t L, L0=sqrt(no_nodes);
igraph_matrix_t dij, lij, kij;
igraph_real_t max_dij;
igraph_vector_t D1, D2;
igraph_integer_t i, j, m;
if (maxiter < 0) {
IGRAPH_ERROR("Number of iterations must be non-negatice in "
"Kamada-Kawai layout", IGRAPH_EINVAL);
}
if (kkconst <= 0) {
IGRAPH_ERROR("`K' constant must be positive in Kamada-Kawai layout",
IGRAPH_EINVAL);
}
if (use_seed && (igraph_matrix_nrow(res) != no_nodes ||
igraph_matrix_ncol(res) != 2)) {
IGRAPH_ERROR("Invalid start position matrix size in "
"Kamada-Kawai layout", IGRAPH_EINVAL);
}
if (weights && igraph_vector_size(weights) != no_edges) {
IGRAPH_ERROR("Invalid weight vector length", IGRAPH_EINVAL);
}
if (minx && igraph_vector_size(minx) != no_nodes) {
IGRAPH_ERROR("Invalid minx vector length", IGRAPH_EINVAL);
}
if (maxx && igraph_vector_size(maxx) != no_nodes) {
IGRAPH_ERROR("Invalid maxx vector length", IGRAPH_EINVAL);
}
if (minx && maxx && !igraph_vector_all_le(minx, maxx)) {
IGRAPH_ERROR("minx must not be greater than maxx", IGRAPH_EINVAL);
}
if (miny && igraph_vector_size(miny) != no_nodes) {
IGRAPH_ERROR("Invalid miny vector length", IGRAPH_EINVAL);
}
if (maxy && igraph_vector_size(maxy) != no_nodes) {
IGRAPH_ERROR("Invalid maxy vector length", IGRAPH_EINVAL);
}
if (miny && maxy && !igraph_vector_all_le(miny, maxy)) {
IGRAPH_ERROR("miny must not be greater than maxy", IGRAPH_EINVAL);
}
if (!use_seed) {
if (minx || maxx || miny || maxy) {
const igraph_real_t width=sqrt(no_nodes), height=width;
IGRAPH_CHECK(igraph_matrix_resize(res, no_nodes, 2));
RNG_BEGIN();
for (i=0; i<no_nodes; i++) {
igraph_real_t x1=minx ? VECTOR(*minx)[i] : -width/2;
igraph_real_t x2=maxx ? VECTOR(*maxx)[i] : width/2;
igraph_real_t y1=miny ? VECTOR(*miny)[i] : -height/2;
igraph_real_t y2=maxy ? VECTOR(*maxy)[i] : height/2;
if (!igraph_finite(x1)) { x1 = -width/2; }
if (!igraph_finite(x2)) { x2 = width/2; }
if (!igraph_finite(y1)) { y1 = -height/2; }
if (!igraph_finite(y2)) { y2 = height/2; }
MATRIX(*res, i, 0) = RNG_UNIF(x1, x2);
MATRIX(*res, i, 1) = RNG_UNIF(y1, y2);
}
RNG_END();
} else {
igraph_layout_circle(graph, res, /* order= */ igraph_vss_all());
}
}
if (no_nodes <= 1) { return 0; }
IGRAPH_MATRIX_INIT_FINALLY(&dij, no_nodes, no_nodes);
IGRAPH_MATRIX_INIT_FINALLY(&kij, no_nodes, no_nodes);
IGRAPH_MATRIX_INIT_FINALLY(&lij, no_nodes, no_nodes);
IGRAPH_CHECK(igraph_shortest_paths_dijkstra(graph, &dij, igraph_vss_all(),
igraph_vss_all(), weights,
IGRAPH_ALL));
max_dij = 0.0;
for (i=0; i<no_nodes; i++) {
for (j=i+1; j<no_nodes; j++) {
if (!igraph_finite(MATRIX(dij, i, j))) { continue; }
if (MATRIX(dij, i, j) > max_dij) { max_dij = MATRIX(dij, i, j); }
}
}
for (i=0; i<no_nodes; i++) {
for (j=0; j<no_nodes; j++) {
if (MATRIX(dij, i, j) > max_dij) { MATRIX(dij, i, j) = max_dij; }
}
}
L = L0 / max_dij;
for (i=0; i<no_nodes; i++) {
for (j=0; j<no_nodes; j++) {
igraph_real_t tmp=MATRIX(dij, i, j) * MATRIX(dij, i, j);
if (i==j) { continue; }
MATRIX(kij, i, j) = kkconst / tmp;
MATRIX(lij, i, j) = L * MATRIX(dij, i, j);
}
}
/* Initialize delta */
IGRAPH_VECTOR_INIT_FINALLY(&D1, no_nodes);
IGRAPH_VECTOR_INIT_FINALLY(&D2, no_nodes);
for (m=0; m<no_nodes; m++) {
igraph_real_t myD1=0.0, myD2=0.0;
for (i=0; i<no_nodes; i++) {
if (i==m) { continue; }
igraph_real_t dx=MATRIX(*res, m, 0) - MATRIX(*res, i, 0);
igraph_real_t dy=MATRIX(*res, m, 1) - MATRIX(*res, i, 1);
igraph_real_t mi_dist=sqrt(dx * dx + dy * dy);
myD1 += MATRIX(kij, m, i) * (dx - MATRIX(lij, m, i) * dx / mi_dist);
myD2 += MATRIX(kij, m, i) * (dy - MATRIX(lij, m, i) * dy / mi_dist);
}
VECTOR(D1)[m] = myD1;
VECTOR(D2)[m] = myD2;
}
for (j=0; j<maxiter; j++) {
igraph_real_t myD1=0.0, myD2=0.0, A=0.0, B=0.0, C=0.0;
igraph_real_t max_delta, delta_x, delta_y;
igraph_real_t old_x, old_y, new_x, new_y;
/* Select maximal delta */
m=0; max_delta=-1;
for (i=0; i<no_nodes; i++) {
igraph_real_t delta=(VECTOR(D1)[i] * VECTOR(D1)[i] +
VECTOR(D2)[i] * VECTOR(D2)[i]);
if (delta > max_delta) {
m=i; max_delta=delta;
}
}
if (max_delta < epsilon) { break; }
old_x=MATRIX(*res, m, 0);
old_y=MATRIX(*res, m, 1);
/* Calculate D1 and D2, A, B, C */
for (i=0; i<no_nodes; i++) {
if (i==m) { continue; }
igraph_real_t dx=old_x - MATRIX(*res, i, 0);
igraph_real_t dy=old_y - MATRIX(*res, i, 1);
igraph_real_t dist=sqrt(dx * dx + dy * dy);
igraph_real_t den=dist * (dx * dx + dy * dy);
A += MATRIX(kij, m, i) * (1 - MATRIX(lij, m, i) * dy * dy / den);
B += MATRIX(kij, m, i) * MATRIX(lij, m, i) * dx * dy / den;
C += MATRIX(kij, m, i) * (1 - MATRIX(lij, m, i) * dx * dx / den);
}
myD1 = VECTOR(D1)[m];
myD2 = VECTOR(D2)[m];
/* Need to solve some linear equations */
delta_y = (B * myD1 - myD2 * A) / (C * A - B * B);
delta_x = - (myD1 + B * delta_y) / A;
new_x = old_x + delta_x;
new_y = old_y + delta_y;
/* Limits, if given */
if (minx && new_x < VECTOR(*minx)[m]) { new_x = VECTOR(*minx)[m]; }
if (maxx && new_x > VECTOR(*maxx)[m]) { new_x = VECTOR(*maxx)[m]; }
if (miny && new_y < VECTOR(*miny)[m]) { new_y = VECTOR(*miny)[m]; }
if (maxy && new_y > VECTOR(*maxy)[m]) { new_y = VECTOR(*maxy)[m]; }
/* Update delta, only with/for the affected node */
VECTOR(D1)[m] = VECTOR(D2)[m] = 0.0;
for (i=0; i<no_nodes; i++) {
if (i==m) { continue; }
igraph_real_t old_dx=old_x - MATRIX(*res, i, 0);
igraph_real_t old_dy=old_y - MATRIX(*res, i, 1);
igraph_real_t old_mi_dist=sqrt(old_dx * old_dx + old_dy * old_dy);
igraph_real_t new_dx=new_x - MATRIX(*res, i, 0);
igraph_real_t new_dy=new_y - MATRIX(*res, i, 1);
igraph_real_t new_mi_dist=sqrt(new_dx * new_dx + new_dy * new_dy);
VECTOR(D1)[i] -= MATRIX(kij, m, i) *
(-old_dx + MATRIX(lij, m, i) * old_dx / old_mi_dist);
VECTOR(D2)[i] -= MATRIX(kij, m, i) *
(-old_dy + MATRIX(lij, m, i) * old_dy / old_mi_dist);
VECTOR(D1)[i] += MATRIX(kij, m, i) *
(-new_dx + MATRIX(lij, m, i) * new_dx / new_mi_dist);
VECTOR(D2)[i] += MATRIX(kij, m, i) *
(-new_dy + MATRIX(lij, m, i) * new_dy / new_mi_dist);
VECTOR(D1)[m] += MATRIX(kij, m, i) *
(new_dx - MATRIX(lij, m, i) * new_dx / new_mi_dist);
VECTOR(D2)[m] += MATRIX(kij, m, i) *
(new_dy - MATRIX(lij, m, i) * new_dy / new_mi_dist);
}
/* Update coordinates*/
MATRIX(*res, m, 0) = new_x;
MATRIX(*res, m, 1) = new_y;
}
igraph_vector_destroy(&D2);
igraph_vector_destroy(&D1);
igraph_matrix_destroy(&lij);
igraph_matrix_destroy(&kij);
igraph_matrix_destroy(&dij);
IGRAPH_FINALLY_CLEAN(5);
return 0;
}
int igraph_layout_kamada_kawai_3d(const igraph_t *graph, igraph_matrix_t *res,
igraph_bool_t use_seed, igraph_integer_t maxiter,
igraph_real_t epsilon, igraph_real_t kkconst,
const igraph_vector_t *weights,
const igraph_vector_t *minx, const igraph_vector_t *maxx,
const igraph_vector_t *miny, const igraph_vector_t *maxy,
const igraph_vector_t *minz, const igraph_vector_t *maxz) {
igraph_integer_t no_nodes=igraph_vcount(graph);
igraph_integer_t no_edges=igraph_ecount(graph);
igraph_real_t L, L0=sqrt(no_nodes);
igraph_matrix_t dij, lij, kij;
igraph_real_t max_dij;
igraph_vector_t D1, D2, D3;
igraph_integer_t i, j, m;
if (maxiter < 0) {
IGRAPH_ERROR("Number of iterations must be non-negatice in "
"Kamada-Kawai layout", IGRAPH_EINVAL);
}
if (kkconst <= 0) {
IGRAPH_ERROR("`K' constant must be positive in Kamada-Kawai layout",
IGRAPH_EINVAL);
}
if (use_seed && (igraph_matrix_nrow(res) != no_nodes ||
igraph_matrix_ncol(res) != 3)) {
IGRAPH_ERROR("Invalid start position matrix size in "
"3d Kamada-Kawai layout", IGRAPH_EINVAL);
}
if (weights && igraph_vector_size(weights) != no_edges) {
IGRAPH_ERROR("Invalid weight vector length", IGRAPH_EINVAL);
}
if (minx && igraph_vector_size(minx) != no_nodes) {
IGRAPH_ERROR("Invalid minx vector length", IGRAPH_EINVAL);
}
if (maxx && igraph_vector_size(maxx) != no_nodes) {
IGRAPH_ERROR("Invalid maxx vector length", IGRAPH_EINVAL);
}
if (minx && maxx && !igraph_vector_all_le(minx, maxx)) {
IGRAPH_ERROR("minx must not be greater than maxx", IGRAPH_EINVAL);
}
if (miny && igraph_vector_size(miny) != no_nodes) {
IGRAPH_ERROR("Invalid miny vector length", IGRAPH_EINVAL);
}
if (maxy && igraph_vector_size(maxy) != no_nodes) {
IGRAPH_ERROR("Invalid maxy vector length", IGRAPH_EINVAL);
}
if (miny && maxy && !igraph_vector_all_le(miny, maxy)) {
IGRAPH_ERROR("miny must not be greater than maxy", IGRAPH_EINVAL);
}
if (minz && igraph_vector_size(minz) != no_nodes) {
IGRAPH_ERROR("Invalid minz vector length", IGRAPH_EINVAL);
}
if (maxz && igraph_vector_size(maxz) != no_nodes) {
IGRAPH_ERROR("Invalid maxz vector length", IGRAPH_EINVAL);
}
if (minz && maxz && !igraph_vector_all_le(minz, maxz)) {
IGRAPH_ERROR("minz must not be greater than maxz", IGRAPH_EINVAL);
}
if (!use_seed) {
if (minx || maxx || miny || maxy || minz || maxz) {
const igraph_real_t width=sqrt(no_nodes), height=width, depth=width;
IGRAPH_CHECK(igraph_matrix_resize(res, no_nodes, 3));
RNG_BEGIN();
for (i=0; i<no_nodes; i++) {
igraph_real_t x1=minx ? VECTOR(*minx)[i] : -width/2;
igraph_real_t x2=maxx ? VECTOR(*maxx)[i] : width/2;
igraph_real_t y1=miny ? VECTOR(*miny)[i] : -height/2;
igraph_real_t y2=maxy ? VECTOR(*maxy)[i] : height/2;
igraph_real_t z1=minz ? VECTOR(*minz)[i] : -depth/2;
igraph_real_t z2=maxz ? VECTOR(*maxz)[i] : depth/2;
if (!igraph_finite(x1)) { x1 = -width/2; }
if (!igraph_finite(x2)) { x2 = width/2; }
if (!igraph_finite(y1)) { y1 = -height/2; }
if (!igraph_finite(y2)) { y2 = height/2; }
if (!igraph_finite(z1)) { z1 = -depth/2; }
if (!igraph_finite(z2)) { z2 = depth/2; }
MATRIX(*res, i, 0) = RNG_UNIF(x1, x2);
MATRIX(*res, i, 1) = RNG_UNIF(y1, y2);
MATRIX(*res, i, 2) = RNG_UNIF(z1, z2);
}
RNG_END();
} else {
igraph_layout_sphere(graph, res);
}
}
if (no_nodes <= 1) { return 0; }
IGRAPH_MATRIX_INIT_FINALLY(&dij, no_nodes, no_nodes);
IGRAPH_MATRIX_INIT_FINALLY(&kij, no_nodes, no_nodes);
IGRAPH_MATRIX_INIT_FINALLY(&lij, no_nodes, no_nodes);
IGRAPH_CHECK(igraph_shortest_paths_dijkstra(graph, &dij, igraph_vss_all(),
igraph_vss_all(), weights,
IGRAPH_ALL));
max_dij = 0.0;
for (i=0; i<no_nodes; i++) {
for (j=i+1; j<no_nodes; j++) {
if (!igraph_finite(MATRIX(dij, i, j))) { continue; }
if (MATRIX(dij, i, j) > max_dij) { max_dij = MATRIX(dij, i, j); }
}
}
for (i=0; i<no_nodes; i++) {
for (j=0; j<no_nodes; j++) {
if (MATRIX(dij, i, j) > max_dij) { MATRIX(dij, i, j) = max_dij; }
}
}
L = L0 / max_dij;
for (i=0; i<no_nodes; i++) {
for (j=0; j<no_nodes; j++) {
igraph_real_t tmp=MATRIX(dij, i, j) * MATRIX(dij, i, j);
if (i==j) { continue; }
MATRIX(kij, i, j) = kkconst / tmp;
MATRIX(lij, i, j) = L * MATRIX(dij, i, j);
}
}
/* Initialize delta */
IGRAPH_VECTOR_INIT_FINALLY(&D1, no_nodes);
IGRAPH_VECTOR_INIT_FINALLY(&D2, no_nodes);
IGRAPH_VECTOR_INIT_FINALLY(&D3, no_nodes);
for (m=0; m<no_nodes; m++) {
igraph_real_t myD1=0.0, myD2=0.0, myD3=0.0;
for (i=0; i<no_nodes; i++) {
if (i==m) { continue; }
igraph_real_t dx=MATRIX(*res, m, 0) - MATRIX(*res, i, 0);
igraph_real_t dy=MATRIX(*res, m, 1) - MATRIX(*res, i, 1);
igraph_real_t dz=MATRIX(*res, m, 2) - MATRIX(*res, i, 2);
igraph_real_t mi_dist=sqrt(dx * dx + dy * dy + dz * dz);
myD1 += MATRIX(kij, m, i) * (dx - MATRIX(lij, m, i) * dx / mi_dist);
myD2 += MATRIX(kij, m, i) * (dy - MATRIX(lij, m, i) * dy / mi_dist);
myD3 += MATRIX(kij, m, i) * (dz - MATRIX(lij, m, i) * dz / mi_dist);
}
VECTOR(D1)[m] = myD1;
VECTOR(D2)[m] = myD2;
VECTOR(D3)[m] = myD3;
}
for (j=0; j<maxiter; j++) {
igraph_real_t Ax=0.0, Ay=0.0, Az=0.0;
igraph_real_t Axx=0.0, Axy=0.0, Axz=0.0, Ayy=0.0, Ayz=0.0, Azz=0.0;
igraph_real_t max_delta, delta_x, delta_y, delta_z;
igraph_real_t old_x, old_y, old_z, new_x, new_y, new_z;
igraph_real_t detnum;
/* Select maximal delta */
m=0; max_delta=-1;
for (i=0; i<no_nodes; i++) {
igraph_real_t delta=(VECTOR(D1)[i] * VECTOR(D1)[i] +
VECTOR(D2)[i] * VECTOR(D2)[i] +
VECTOR(D3)[i] * VECTOR(D3)[i]);
if (delta > max_delta) {
m=i; max_delta=delta;
}
}
if (max_delta < epsilon) { break; }
old_x=MATRIX(*res, m, 0);
old_y=MATRIX(*res, m, 1);
old_z=MATRIX(*res, m, 2);
/* Calculate D1, D2 and D3, and other coefficients */
for (i=0; i<no_nodes; i++) {
if (i==m) { continue; }
igraph_real_t dx=old_x - MATRIX(*res, i, 0);
igraph_real_t dy=old_y - MATRIX(*res, i, 1);
igraph_real_t dz=old_z - MATRIX(*res, i, 2);
igraph_real_t dist=sqrt(dx * dx + dy * dy + dz *dz);
igraph_real_t den=dist * (dx * dx + dy * dy + dz * dz);
igraph_real_t k_mi=MATRIX(kij, m, i);
igraph_real_t l_mi=MATRIX(lij, m, i);
Axx += k_mi * (1 - l_mi * (dy*dy + dz*dz) / den);
Ayy += k_mi * (1 - l_mi * (dx*dx + dz*dz) / den);
Azz += k_mi * (1 - l_mi * (dx*dx + dy*dy) / den);
Axy += k_mi * l_mi * dx * dy / den;
Axz += k_mi * l_mi * dx * dz / den;
Ayz += k_mi * l_mi * dy * dz / den;
}
Ax = -VECTOR(D1)[m];
Ay = -VECTOR(D2)[m];
Az = -VECTOR(D3)[m];
/* Need to solve some linear equations, we just use Cramer's rule */
#define DET(a,b,c,d,e,f,g,h,i) ((a*e*i+b*f*g+c*d*h)-(c*e*g+b*d*i+a*f*h))
detnum = DET(Axx,Axy,Axz, Axy,Ayy,Ayz, Axz,Ayz,Azz);
delta_x = DET(Ax ,Ay ,Az , Axy,Ayy,Ayz, Axz,Ayz,Azz) / detnum;
delta_y = DET(Axx,Axy,Axz, Ax ,Ay ,Az , Axz,Ayz,Azz) / detnum;
delta_z = DET(Axx,Axy,Axz, Axy,Ayy,Ayz, Ax ,Ay ,Az ) / detnum;
new_x = old_x + delta_x;
new_y = old_y + delta_y;
new_z = old_z + delta_z;
/* Limits, if given */
if (minx && new_x < VECTOR(*minx)[m]) { new_x = VECTOR(*minx)[m]; }
if (maxx && new_x > VECTOR(*maxx)[m]) { new_x = VECTOR(*maxx)[m]; }
if (miny && new_y < VECTOR(*miny)[m]) { new_y = VECTOR(*miny)[m]; }
if (maxy && new_y > VECTOR(*maxy)[m]) { new_y = VECTOR(*maxy)[m]; }
if (minz && new_z < VECTOR(*minz)[m]) { new_z = VECTOR(*minz)[m]; }
if (maxz && new_z > VECTOR(*maxz)[m]) { new_z = VECTOR(*maxz)[m]; }
/* Update delta, only with/for the affected node */
VECTOR(D1)[m] = VECTOR(D2)[m] = VECTOR(D3)[m] = 0.0;
for (i=0; i<no_nodes; i++) {
if (i==m) { continue; }
igraph_real_t old_dx=old_x - MATRIX(*res, i, 0);
igraph_real_t old_dy=old_y - MATRIX(*res, i, 1);
igraph_real_t old_dz=old_z - MATRIX(*res, i, 2);
igraph_real_t old_mi_dist=sqrt(old_dx * old_dx + old_dy * old_dy +
old_dz * old_dz);
igraph_real_t new_dx=new_x - MATRIX(*res, i, 0);
igraph_real_t new_dy=new_y - MATRIX(*res, i, 1);
igraph_real_t new_dz=new_z - MATRIX(*res, i, 2);
igraph_real_t new_mi_dist=sqrt(new_dx * new_dx + new_dy * new_dy +
new_dz * new_dz);
VECTOR(D1)[i] -= MATRIX(kij, m, i) *
(-old_dx + MATRIX(lij, m, i) * old_dx / old_mi_dist);
VECTOR(D2)[i] -= MATRIX(kij, m, i) *
(-old_dy + MATRIX(lij, m, i) * old_dy / old_mi_dist);
VECTOR(D3)[i] -= MATRIX(kij, m, i) *
(-old_dz + MATRIX(lij, m, i) * old_dz / old_mi_dist);
VECTOR(D1)[i] += MATRIX(kij, m, i) *
(-new_dx + MATRIX(lij, m, i) * new_dx / new_mi_dist);
VECTOR(D2)[i] += MATRIX(kij, m, i) *
(-new_dy + MATRIX(lij, m, i) * new_dy / new_mi_dist);
VECTOR(D3)[i] += MATRIX(kij, m, i) *
(-new_dz + MATRIX(lij, m, i) * new_dz / new_mi_dist);
VECTOR(D1)[m] += MATRIX(kij, m, i) *
(new_dx - MATRIX(lij, m, i) * new_dx / new_mi_dist);
VECTOR(D2)[m] += MATRIX(kij, m, i) *
(new_dy - MATRIX(lij, m, i) * new_dy / new_mi_dist);
VECTOR(D3)[m] += MATRIX(kij, m, i) *
(new_dz - MATRIX(lij, m, i) * new_dz / new_mi_dist);
}
/* Update coordinates*/
MATRIX(*res, m, 0) = new_x;
MATRIX(*res, m, 1) = new_y;
MATRIX(*res, m, 2) = new_z;
}
igraph_vector_destroy(&D3);
igraph_vector_destroy(&D2);
igraph_vector_destroy(&D1);
igraph_matrix_destroy(&lij);
igraph_matrix_destroy(&kij);
igraph_matrix_destroy(&dij);
IGRAPH_FINALLY_CLEAN(6);
return 0;
}