# hm.phonemes

Mnemonic tools using phonemes

### Functions

| [`keys_for_value`](#hm.phonemes.keys_for_value)(d)   | An inverse of dict `d`.   |
|----------------------------------------------------------------------|---------------------------|

### Classes

| [`MajorSystem`](#hm.phonemes.MajorSystem)(\*[, url_term_and_phones])   | See:    [https://en.wikipedia.org/wiki/Mnemonic_major_system](https://en.wikipedia.org/wiki/Mnemonic_major_system)   |
|-------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------|
| `Phone`(\*[, url_term_and_phones])                                                        |                                                                                                                      |

### *class* hm.phonemes.MajorSystem(, url_term_and_phones='http://svn.code.sf.net/p/cmusphinx/code/trunk/cmudict/cmudict-0.7b')

Bases: `Phone`

See:    [https://en.wikipedia.org/wiki/Mnemonic_major_system](https://en.wikipedia.org/wiki/Mnemonic_major_system)

```pycon
>>> m = MajorSystem()
```

The “Mnemonic Major System” ([https://en.wikipedia.org/wiki/Mnemonic_major_system](https://en.wikipedia.org/wiki/Mnemonic_major_system))
assigns a set of similar phonemes to each digit:

```pycon
>>> assert m.phones_for_num == {
...     0: {'S', 'Z'},
...     1: {'D', 'DH', 'T', 'TH'},
...     2: {'N'},
...     3: {'M'},
...     4: {'R'},
...     5: {'L'},
...     6: {'CH', 'JH', 'SH'},
...     7: {'G', 'K'},
...     8: {'F', 'V'},
...     9: {'B', 'P'}
... }
```

As a consequence these phonemes are mapped to numbers:

```pycon
>>> assert m.num_of_phone == {
...     'B': 9,
...     'CH': 6,
...     'D': 1,
...     'DH': 1,
...     'F': 8,
...     'G': 7,
...     'JH': 6,
...     'K': 7,
...     'L': 5,
...     'M': 3,
...     'N': 2,
...     'P': 9,
...     'R': 4,
...     'S': 0,
...     'SH': 6,
...     'T': 1,
...     'TH': 1,
...     'V': 8,
...     'Z': 0
... }
```

Any sentence has a corresponding phoneme sequence:

```pycon
>>> m.term_to_phones('wild cat')
['W', 'AY1', 'L', 'D', 'K', 'AE1', 'T']
```

The system doesn’t contain all phonemes; only some of the consonant phonemes.
So if we only keep those phonemes that the system covers, we get:

```pycon
>>> m.term_to_mst_sequence('wild cat')
['L', 'D', 'K', 'T']
```

Which corresponds to a number.

```pycon
>>> m.term_to_nums('wild cat')
[5, 1, 7, 1]
```

But really, the system is used to be able to create words (therefore images)
that correspond to a sequence of numbers, so that one can remember them:

```pycon
>>> m.terms_of_numstr['3214']
['hammontree', 'mahindra', 'manteer', 'mantra', 'mentor', 'minteer', 'mondry',
'monetary', 'monteiro', 'monterey', 'montero', 'monterrey', 'montrouis',
'montroy', 'montuori', 'omohundro']
```

### hm.phonemes.keys_for_value(d)

An inverse of dict `d`.
If `d` is a mapping of `(key, value)`, `keys_for_value` will return
a dict of `(unique_value, group_of_key)` items.