/* Each unit test is given an alignment with certain known
* properties:
* seqs 0,1 are identical
* seqs 0,2 are completely different
* seqs 3..N are random
* The alignment may contain gaps, so don't assume that the
* # of compared residues == alignment length. The alignment
* contains only canonical residues, because one of our tests
* is that C and X functions give the same results.
*/
static int
utest_CPairId(char **as, int N)
{
double pid;
int nid;
int nres;
int L;
int i,j;
/* Self comparison gives identity = 1. */
L = strlen(as[0]);
if (esl_dst_CPairId(as[0], as[0], &pid, &nid, &nres) != eslOK) abort();
if (pid != 1.0 || nid != L || nres > L) abort();
/* So does 0,1 comparison */
if (esl_dst_CPairId(as[0], as[1], &pid, &nid, &nres) != eslOK) abort();
if (pid != 1.0 || nid != L || nres > L) abort();
/* 0,2 comparison gives 0.0, 0 */
if (esl_dst_CPairId(as[0], as[2], &pid, &nid, &nres) != eslOK) abort();
if (pid != 0.0 || nid != 0 || nres > L) abort();
/* remaining comparisons shouldn't fail */
for (i = 3; i < N; i++)
for (j = i; j < N; j++)
{
if (esl_dst_CPairId(as[i], as[j], &pid, &nid, &nres) != eslOK) abort();
if (pid < 0. || pid > 1. || nid < 0 || nid > L || nres > L) abort();
}
/* API should accept NULL for return values */
if (esl_dst_CPairId(as[0], as[0], NULL, NULL, NULL) != eslOK) abort();
return eslOK;
}
/* Function: esl_dst_CPairIdMx()
* Synopsis: NxN identity matrix for N aligned text sequences.
* Incept: SRE, Thu Apr 27 08:46:08 2006 [New York]
*
* Purpose: Given a multiple sequence alignment <as>, consisting
* of <N> aligned character strings; calculate
* a symmetric fractional pairwise identity matrix by $N(N-1)/2$
* calls to <esl_dst_CPairId()>, and return it in
* <ret_D>.
*
* Args: as - aligned seqs (all same length), [0..N-1]
* N - # of aligned sequences
* ret_S - RETURN: symmetric fractional identity matrix
*
* Returns: <eslOK> on success, and <ret_S> contains the fractional
* identity matrix. Caller free's <S> with
* <esl_dmatrix_Destroy()>.
*
* Throws: <eslEINVAL> if a seq has a different
* length than others. On failure, <ret_D> is returned <NULL>
* and state of inputs is unchanged.
*/
int
esl_dst_CPairIdMx(char **as, int N, ESL_DMATRIX **ret_S)
{
ESL_DMATRIX *S = NULL;
int status;
int i,j;
if (( S = esl_dmatrix_Create(N,N) ) == NULL) goto ERROR;
for (i = 0; i < N; i++)
{
S->mx[i][i] = 1.;
for (j = i+1; j < N; j++)
{
status = esl_dst_CPairId(as[i], as[j], &(S->mx[i][j]), NULL, NULL);
if (status != eslOK)
ESL_XEXCEPTION(status, "Pairwise identity calculation failed at seqs %d,%d\n", i,j);
S->mx[j][i] = S->mx[i][j];
}
}
if (ret_S != NULL) *ret_S = S; else esl_dmatrix_Destroy(S);
return eslOK;
ERROR:
if (S != NULL) esl_dmatrix_Destroy(S);
if (ret_S != NULL) *ret_S = NULL;
return status;
}
/* Function: esl_msaweight_IDFilter()
* Synopsis: Filter by %ID.
* Incept: ER, Wed Oct 29 10:06:43 2008 [Janelia]
*
* Purpose: Constructs a new alignment by removing near-identical
* sequences from a given alignment (where identity is
* calculated *based on the alignment*).
* Does not affect the given alignment.
* Keeps earlier sequence, discards later one.
*
* Usually called as an ad hoc sequence "weighting" mechanism.
*
* Limitations:
* Unparsed Stockholm markup is not propagated into the
* new alignment.
*
* Return: <eslOK> on success, and the <newmsa>.
*
* Throws: <eslEMEM> on allocation error. <eslEINVAL> if a pairwise
* identity calculation fails because of corrupted sequence
* data. In either case, the <msa> is unmodified.
*
* Xref: squid::weight.c::FilterAlignment().
*/
int
esl_msaweight_IDFilter(const ESL_MSA *msa, double maxid, ESL_MSA **ret_newmsa)
{
int *list = NULL; /* array of seqs in new msa */
int *useme = NULL; /* TRUE if seq is kept in new msa */
int nnew; /* number of seqs in new alignment */
double ident; /* pairwise percentage id */
int i,j; /* seqs counters*/
int remove; /* TRUE if sq is to be removed */
int status;
/* Contract checks
*/
ESL_DASSERT1( (msa != NULL) );
ESL_DASSERT1( (msa->nseq >= 1) );
ESL_DASSERT1( (msa->alen >= 1) );
/* allocate */
ESL_ALLOC(list, sizeof(int) * msa->nseq);
ESL_ALLOC(useme, sizeof(int) * msa->nseq);
esl_vec_ISet(useme, msa->nseq, 0); /* initialize array */
/* find which seqs to keep (list) */
nnew = 0;
for (i = 0; i < msa->nseq; i++)
{
remove = FALSE;
for (j = 0; j < nnew; j++)
{
if (! (msa->flags & eslMSA_DIGITAL)) {
if ((status = esl_dst_CPairId(msa->aseq[i], msa->aseq[list[j]], &ident, NULL, NULL)) != eslOK) goto ERROR;
}
#ifdef eslAUGMENT_ALPHABET
else {
if ((status = esl_dst_XPairId(msa->abc, msa->ax[i], msa->ax[list[j]], &ident, NULL, NULL)) != eslOK) goto ERROR;
}
#endif
if (ident > maxid)
{
remove = TRUE;
break;
}
}
if (remove == FALSE) {
list[nnew++] = i;
useme[i] = TRUE;
}
}
if ((status = esl_msa_SequenceSubset(msa, useme, ret_newmsa)) != eslOK) goto ERROR;
free(list);
free(useme);
return eslOK;
ERROR:
if (list != NULL) free(list);
if (useme != NULL) free(useme);
return status;
}
/* Function: esl_dst_CAverageId()
* Synopsis: Calculate avg identity for multiple alignment
* Incept: SRE, Fri May 18 15:02:38 2007 [Janelia]
*
* Purpose: Calculates the average pairwise fractional identity in
* a multiple sequence alignment <as>, consisting of <N>
* aligned character sequences of identical length.
*
* If an exhaustive calculation would require more than
* <max_comparisons> pairwise comparisons, then instead of
* looking at all pairs, calculate the average over a
* stochastic sample of <max_comparisons> random pairs.
* This allows the routine to work efficiently even on very
* deep MSAs.
*
* Each fractional pairwise identity (range $[0..$ pid $..1]$
* is calculated using <esl_dsq_CPairId()>.
*
* Returns: <eslOK> on success, and <*ret_id> contains the average
* fractional identity.
*
* Throws: <eslEMEM> on allocation failure.
* <eslEINVAL> if any of the aligned sequence pairs aren't
* of the same length.
* In either case, <*ret_id> is set to 0.
*/
int
esl_dst_CAverageId(char **as, int N, int max_comparisons, double *ret_id)
{
int status;
double id;
double sum;
int i,j,n;
if (N <= 1) { *ret_id = 1.; return eslOK; }
*ret_id = 0.;
/* Is nseq small enough that we can average over all pairwise comparisons? */
if ((N * (N-1) / 2) <= max_comparisons)
{
for (i = 0; i < N; i++)
for (j = i+1; j < N; j++)
{
if ((status = esl_dst_CPairId(as[i], as[j], &id, NULL, NULL)) != eslOK) return status;
sum += id;
}
id /= (double) (N * (N-1) / 2);
}
/* If nseq is large, calculate average over a stochastic sample. */
else
{
ESL_RANDOMNESS *r = esl_randomness_CreateTimeseeded();
for (n = 0; n < max_comparisons; n++)
{
do { i = esl_rnd_Roll(r, N); j = esl_rnd_Roll(r, N); } while (j == i); /* make sure j != i */
if ((status = esl_dst_CPairId(as[i], as[j], &id, NULL, NULL)) != eslOK) return status;
sum += id;
}
id /= (double) max_comparisons;
esl_randomness_Destroy(r);
}
*ret_id = id;
return eslOK;
}
/* Definition of %id linkage in text-mode aligned seqs (>= maxid): */
static int
msacluster_clinkage(const void *v1, const void *v2, const void *p, int *ret_link)
{
char *as1 = *(char **) v1;
char *as2 = *(char **) v2;
double maxid = *(double *) p;
double pid;
int status = eslOK;
#if defined(eslMSACLUSTER_REGRESSION) || defined(eslMSAWEIGHT_REGRESSION)
pid = 1. - squid_distance(as1, as2);
#else
if ((status = esl_dst_CPairId(as1, as2, &pid, NULL, NULL)) != eslOK) return status;
#endif
*ret_link = (pid >= maxid ? TRUE : FALSE);
return status;
}
static int
utest_XPairId(ESL_ALPHABET *abc, char **as, ESL_DSQ **ax, int N)
{
double pid, pid2;
int nid, nid2;
int nres, nres2;
int dL, L;
int i,j;
/* Self comparison gives identity = 1. */
dL = esl_abc_dsqlen(ax[0]);
L = strlen(as[0]);
if (dL != L) abort();
if (esl_dst_XPairId(abc, ax[0], ax[0], &pid, &nid, &nres) != eslOK) abort();
if (pid != 1.0 || nid != L || nres > dL) abort();
/* So does 0,1 comparison */
if (esl_dst_XPairId(abc, ax[0], ax[1], &pid, &nid, &nres) != eslOK) abort();
if (pid != 1.0 || nid != L || nres > L) abort();
/* 0,2 comparison gives 0.0, 0 */
if (esl_dst_XPairId(abc, ax[0], ax[2], &pid, &nid, &nres) != eslOK) abort();
if (pid != 0.0 || nid != 0 || nres > L) abort();
/* remaining comparisons shouldn't fail, and should be identical to text mode */
for (i = 3; i < N; i++)
for (j = i; j < N; j++)
{
if (esl_dst_XPairId(abc, ax[i], ax[j], &pid, &nid, &nres) != eslOK) abort();
if (esl_dst_CPairId(as[i], as[j], &pid2, &nid2, &nres2) != eslOK) abort();
if (pid < 0. || pid > 1. || nid < 0 || nid > L || nres > L) abort();
if (pid != pid2 || nid != nid2 || nres != nres2) abort();
}
/* API should accept NULL for return values */
if (esl_dst_XPairId(abc, ax[0], ax[0], NULL, NULL, NULL) != eslOK) abort();
return eslOK;
}
