Mercurial > hg > numerics
annotate numerics/data.py @ 50:e39643d18d82
note to self
| author | Jeff Hammel <k0scist@gmail.com> |
|---|---|
| date | Mon, 19 Jan 2015 12:45:06 -0800 |
| parents | 5caa67643162 |
| children | e7e49b46832b |
| rev | line source |
|---|---|
| 19 | 1 # -*- coding: utf-8 -*- |
| 2 | |
| 3 """ | |
| 4 data models | |
| 5 """ | |
| 6 | |
| 21 | 7 from collections import OrderedDict |
| 8 | |
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9 __all__ = ['ColumnNumberException', 'ColumnLengthException', 'Rows', 'Columns'] |
| 21 | 10 |
| 11 | |
| 12 class ColumnNumberException(Exception): | |
| 13 """ | |
| 14 wrong number of columns: {given} given; {expected} expected | |
| 15 """ | |
| 16 def __init__(self, given, expected): | |
| 17 self.given = given | |
| 18 self.expected = expected | |
| 23 | 19 Exception.__init__(self.__doc__.format(**self.__dict__).strip()) |
| 20 | |
| 21 | |
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22 def transpose(array): |
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23 """makes rows into columns or vice versa""" |
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36e47061187f
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parents:
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24 |
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parents:
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25 if not array: |
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26 return array # nothing to do |
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36e47061187f
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Jeff Hammel <k0scist@gmail.com>
parents:
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27 |
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parents:
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28 n_cols = len(array[0]) |
| 49 | 29 retval = [[]] * n_cols |
| 50 | 30 return zip(*array) |
| 31 # XXX this is a nothing function; we shouldn't use this | |
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parents:
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changeset
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32 |
| 23 | 33 class ColumnLengthException(ColumnNumberException): |
| 34 """ | |
| 35 wrong length of column: {given} given; {expected} expected | |
| 36 """ | |
| 37 # XXX should share ABC, not inherit from ColumnNumberException | |
| 21 | 38 |
| 39 | |
| 40 class Rows(object): | |
| 41 """ | |
| 42 row-based data | |
| 43 """ | |
| 44 | |
| 45 array = OrderedDict | |
| 19 | 46 |
| 21 | 47 def __init__(self, columns, *rows): |
| 48 """ | |
| 49 columns -- column labels | |
| 50 """ | |
| 51 self.column_names = columns | |
| 52 self.rows = [] | |
| 53 | |
| 54 for row in rows: | |
| 55 self += row | |
| 56 | |
| 57 def __iadd__(self, row): | |
| 58 """add a labeled row""" | |
| 59 if len(row) != len(self.columns_names): | |
| 60 raise ColumnNumberException(len(row), len(self.columns_names)) | |
| 61 self.rows.append(self.array(zip(self.columns_names, row))) | |
| 62 | |
| 63 def __len__(self): | |
| 64 return len(self.rows) | |
| 65 | |
| 66 def __getitem__(self, item): | |
| 67 return self.rows[item] | |
| 22 | 68 |
| 69 | |
| 70 class Columns(object): | |
| 71 """ | |
| 72 column-oriented data | |
| 73 """ | |
| 74 | |
| 75 def __init__(self, *columns): | |
| 76 self.columns = OrderedDict() # this should be ordered | |
| 23 | 77 for name, values in columns: |
| 78 self += (name, values) | |
| 79 | |
| 80 def __iadd__(self, item): | |
| 81 column_name, values = item | |
| 82 assert column_name not in self.columns | |
| 83 return self |