| |
| |
| |
| |
| |
| |
| """Bio.SeqIO support for the "tab" (simple tab separated) file format. |
| |
| You are expected to use this module via the Bio.SeqIO functions. |
| |
| The "tab" format is an ad-hoc plain text file format where each sequence is |
| on one (long) line. Each line contains the identifier/description, followed |
| by a tab, followed by the sequence. For example, consider the following |
| short FASTA format file:: |
| |
| >ID123456 possible binding site? |
| CATCNAGATGACACTACGACTACGACTCAGACTAC |
| >ID123457 random sequence |
| ACACTACGACTACGACTCAGACTACAAN |
| |
| Apart from the descriptions, this can be represented in the simple two column |
| tab separated format as follows:: |
| |
| ID123456(tab)CATCNAGATGACACTACGACTACGACTCAGACTAC |
| ID123457(tab)ACACTACGACTACGACTCAGACTACAAN |
| |
| When reading this file, "ID123456" or "ID123457" will be taken as the record's |
| .id and .name property. There is no other information to record. |
| |
| Similarly, when writing to this format, Biopython will ONLY record the record's |
| .id and .seq (and not the description or any other information) as in the |
| example above. |
| """ |
|
|
| from Bio.Seq import Seq |
| from Bio.SeqRecord import SeqRecord |
| from Bio import BiopythonDeprecationWarning |
|
|
| from .Interfaces import _clean |
| from .Interfaces import _get_seq_string |
| from .Interfaces import SequenceIterator |
| from .Interfaces import SequenceWriter |
|
|
| import warnings |
|
|
|
|
| class TabIterator(SequenceIterator): |
| """Parser for tab-delimited files.""" |
|
|
| modes = "t" |
|
|
| def __init__(self, source): |
| """Iterate over tab separated lines as SeqRecord objects. |
| |
| Each line of the file should contain one tab only, dividing the line |
| into an identifier and the full sequence. |
| |
| Arguments: |
| - source - file-like object opened in text mode, or a path to a file |
| |
| The first field is taken as the record's .id and .name (regardless of |
| any spaces within the text) and the second field is the sequence. |
| |
| Any blank lines are ignored. |
| |
| Examples |
| -------- |
| >>> with open("GenBank/NC_005816.tsv") as handle: |
| ... for record in TabIterator(handle): |
| ... print("%s length %i" % (record.id, len(record))) |
| gi|45478712|ref|NP_995567.1| length 340 |
| gi|45478713|ref|NP_995568.1| length 260 |
| gi|45478714|ref|NP_995569.1| length 64 |
| gi|45478715|ref|NP_995570.1| length 123 |
| gi|45478716|ref|NP_995571.1| length 145 |
| gi|45478717|ref|NP_995572.1| length 357 |
| gi|45478718|ref|NP_995573.1| length 138 |
| gi|45478719|ref|NP_995574.1| length 312 |
| gi|45478720|ref|NP_995575.1| length 99 |
| gi|45478721|ref|NP_995576.1| length 90 |
| |
| """ |
| super().__init__(source, fmt="Tab-separated plain-text") |
|
|
| def __next__(self): |
| for line in self.stream: |
| try: |
| title, seq = line.split("\t") |
| except ValueError: |
| if line.strip() == "": |
| |
| continue |
| raise ValueError( |
| "Each line should have one tab separating the" |
| + " title and sequence, this line has %i tabs: %r" |
| % (line.count("\t"), line) |
| ) from None |
| title = title.strip() |
| seq = seq.strip() |
| return SeqRecord(Seq(seq), id=title, name=title, description="") |
| raise StopIteration |
|
|
|
|
| class TabWriter(SequenceWriter): |
| """Class to write simple tab separated format files. |
| |
| Each line consists of "id(tab)sequence" only. |
| |
| Any description, name or other annotation is not recorded. |
| |
| This class is not intended to be used directly. Instead, please use |
| the top level ``Bio.SeqIO.write()`` function with ``format="tab"``. |
| """ |
|
|
| modes = "t" |
|
|
| @classmethod |
| def to_string(cls, record): |
| """Return record as tab separated (id(tab)seq) string.""" |
| title = _clean(record.id) |
| seq = _get_seq_string(record) |
| assert "\t" not in title |
| assert "\n" not in title |
| assert "\r" not in title |
| assert "\t" not in seq |
| assert "\n" not in seq |
| assert "\r" not in seq |
| return f"{title}\t{seq}\n" |
|
|
| def write_record(self, record): |
| """Write a single tab line to the file.""" |
| self.handle.write(self.to_string(record)) |
|
|
|
|
| def as_tab(record): |
| """Return record as tab separated (id(tab)seq) string.""" |
| warnings.warn( |
| """\ |
| TabIO.as_tab is deprecated. |
| |
| Instead of |
| |
| TabIO.as_tab(record) |
| |
| please use |
| |
| format(record, "tab") |
| """, |
| DeprecationWarning, |
| ) |
| return TabWriter.to_string(record) |
|
|
|
|
| if __name__ == "__main__": |
| from Bio._utils import run_doctest |
|
|
| run_doctest(verbose=0) |
|
|