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Datetime, Bytes, Struct, Numpy, Audio, Pygame, Pandas
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@gto76
gto76 committed Feb 19, 2024
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68 changes: 34 additions & 34 deletions README.md
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Expand Up @@ -655,9 +655,9 @@ from dateutil.tz import tzlocal, gettz
### Arithmetics
```python
<bool> = <D/T/DTn> > <D/T/DTn> # Ignores time jumps (fold attribute). Also ==.
<bool> = <DTa> > <DTa> # Ignores time jumps if they share tzinfo object.
<bool> = <DTa> > <DTa> # Ignores jumps if they share tz object. Broken ==.
<TD> = <D/DTn> - <D/DTn> # Ignores jumps. Convert to UTC for actual delta.
<TD> = <DTa> - <DTa> # Ignores time jumps if they share tzinfo object.
<TD> = <DTa> - <DTa> # Ignores jumps if they share tzinfo object.
<D/DT> = <D/DT> ± <TD> # Returned datetime can fall into missing hour.
<TD> = <TD> * <float> # Also: <TD> = abs(<TD>) and <TD> = <TD> ±% <TD>.
<float> = <TD> / <TD> # How many hours/weeks/years are in TD. Also //.
Expand Down Expand Up @@ -1951,26 +1951,26 @@ Bytes
**Bytes object is an immutable sequence of single bytes. Mutable version is called bytearray.**

```python
<bytes> = b'<str>' # Only accepts ASCII characters and \x00-\xff.
<int> = <bytes>[<index>] # Returns an int in range from 0 to 255.
<bytes> = <bytes>[<slice>] # Returns bytes even if it has only one element.
<bytes> = <bytes>.join(<coll_of_bytes>) # Joins elements using bytes as a separator.
<bytes> = b'<str>' # Only accepts ASCII characters and \x00-\xff.
<int> = <bytes>[<index>] # Returns an int in range from 0 to 255.
<bytes> = <bytes>[<slice>] # Returns bytes even if it has only one element.
<bytes> = <bytes>.join(<coll_of_bytes>) # Joins elements using bytes as a separator.
```

### Encode
```python
<bytes> = bytes(<coll_of_ints>) # Ints must be in range from 0 to 255.
<bytes> = bytes(<str>, 'utf-8') # Or: <str>.encode('utf-8')
<bytes> = <int>.to_bytes(n_bytes, …) # `byteorder='big/little', signed=False`.
<bytes> = bytes.fromhex('<hex>') # Hex pairs can be separated by whitespaces.
<bytes> = bytes(<coll_of_ints>) # Ints must be in range from 0 to 255.
<bytes> = bytes(<str>, 'utf-8') # Or: <str>.encode('utf-8')
<bytes> = <int>.to_bytes(n_bytes, …) # `byteorder='big/little', signed=False`.
<bytes> = bytes.fromhex('<hex>') # Hex pairs can be separated by whitespaces.
```

### Decode
```python
<list> = list(<bytes>) # Returns ints in range from 0 to 255.
<str> = str(<bytes>, 'utf-8') # Or: <bytes>.decode('utf-8')
<int> = int.from_bytes(<bytes>, …) # `byteorder='big/little', signed=False`.
'<hex>' = <bytes>.hex() # Returns hex pairs. Accepts `sep=<str>`.
<list> = list(<bytes>) # Returns ints in range from 0 to 255.
<str> = str(<bytes>, 'utf-8') # Or: <bytes>.decode('utf-8')
<int> = int.from_bytes(<bytes>, …) # `byteorder='big/little', signed=False`.
'<hex>' = <bytes>.hex() # Returns hex pairs. Accepts `sep=<str>`.
```

### Read Bytes from File
Expand Down Expand Up @@ -2009,12 +2009,12 @@ b'\x00\x01\x00\x02\x00\x00\x00\x03'
### Format
#### For standard type sizes and manual alignment (padding) start format string with:
* **`'='` - System's byte order (usually little-endian).**
* **`'<'` - Little-endian.**
* **`'<'` - Little-endian (i.e. least significant byte first).**
* **`'>'` - Big-endian (also `'!'`).**

#### Besides numbers, pack() and unpack() also support bytes objects as part of the sequence:
* **`'c'` - A bytes object with a single element. For pad byte use `'x'`.**
* **`'<n>s'` - A bytes object with n elements.**
* **`'<n>s'` - A bytes object with n elements (not effected by byte order).**

#### Integer types. Use a capital letter for unsigned type. Minimum and standard sizes are in brackets:
* **`'b'` - char (1/1)**
Expand Down Expand Up @@ -2414,7 +2414,7 @@ plt.clf() # Clears the figure.

Table
-----
#### Prints a CSV file as an ASCII table:
#### Prints a CSV spreadsheet to the console:
```python
# $ pip3 install tabulate
import csv, tabulate
Expand Down Expand Up @@ -2676,7 +2676,7 @@ import numpy as np
<array> = np.tile/repeat(<array>, <int/list> [, axis]) # Tiles array or repeats its elements.
```
* **Shape is a tuple of dimension sizes. A 100x50 RGB image has shape (50, 100, 3).**
* **Axis is an index of the dimension that gets aggregated. Leftmost dimension has index 0. Summing the RGB image along axis 2 will return a greyscale image with shape (50, 100).**
* **Axis is an index of a dimension. Leftmost dimension has index 0. Summing the RGB image along axis 2 will return a greyscale image with shape (50, 100).**

### Indexing
```perl
Expand Down Expand Up @@ -2858,21 +2858,21 @@ import wave
```

```python
<Wave> = wave.open('<path>', 'rb') # Opens the WAV file.
<int> = <Wave>.getframerate() # Returns number of frames per second.
<int> = <Wave>.getnchannels() # Returns number of samples per frame.
<int> = <Wave>.getsampwidth() # Returns number of bytes per sample.
<params> = <Wave>.getparams() # Returns collection of listed params.
<bytes> = <Wave>.readframes(nframes) # Returns next n frames. All if -1.
<Wave> = wave.open('<path>', 'rb') # Opens the WAV file.
<int> = <Wave>.getframerate() # Returns number of frames per second.
<int> = <Wave>.getnchannels() # Returns number of samples per frame.
<int> = <Wave>.getsampwidth() # Returns number of bytes per sample.
<tuple> = <Wave>.getparams() # Returns namedtuple of all parameters.
<bytes> = <Wave>.readframes(nframes) # Returns next n frames. All if -1.
```

```python
<Wave> = wave.open('<path>', 'wb') # Opens WAV file for writing.
<Wave>.setframerate(<int>) # Pass 44100 for CD, 48000 for video.
<Wave>.setnchannels(<int>) # Pass 1 for mono, 2 for stereo.
<Wave>.setsampwidth(<int>) # Pass 2 for CD, 3 for hi-res sound.
<Wave>.setparams(<params>) # Sets all parameters.
<Wave>.writeframes(<bytes>) # Appends frames to the file.
<Wave> = wave.open('<path>', 'wb') # Creates/truncates a file for writing.
<Wave>.setframerate(<int>) # Pass 44100 for CD, 48000 for video.
<Wave>.setnchannels(<int>) # Pass 1 for mono, 2 for stereo.
<Wave>.setsampwidth(<int>) # Pass 2 for CD, 3 for hi-res sound.
<Wave>.setparams(<tuple>) # Sets all parameters.
<Wave>.writeframes(<bytes>) # Appends frames to the file.
```
* **Bytes object contains a sequence of frames, each consisting of one or more samples.**
* **In a stereo signal, the first sample of a frame belongs to the left channel.**
Expand Down Expand Up @@ -3007,7 +3007,7 @@ while not pg.event.get(pg.QUIT):

```python
<bool> = <Rect>.collidepoint((x, y)) # Checks if rectangle contains the point.
<bool> = <Rect>.colliderect(<Rect>) # Checks if two rectangles overlap.
<bool> = <Rect>.colliderect(<Rect>) # Checks if the two rectangles overlap.
<int> = <Rect>.collidelist(<list_of_Rect>) # Returns index of first colliding Rect or -1.
<list> = <Rect>.collidelistall(<list_of_Rect>) # Returns indexes of all colliding rectangles.
```
Expand All @@ -3025,7 +3025,7 @@ while not pg.event.get(pg.QUIT):
```python
<Surf>.fill(color) # Tuple, Color('#rrggbb[aa]') or Color(<name>).
<Surf>.set_at((x, y), color) # Updates pixel. Also <Surf>.get_at((x, y)).
<Surf>.blit(<Surf>, (x, y)) # Draws passed surface to the surface.
<Surf>.blit(<Surf>, (x, y)) # Draws passed surface at specified location.
```

```python
Expand All @@ -3051,7 +3051,7 @@ rect(<Surf>, color, <Rect>, width=0) # Also polygon(<Surf>, color, po
### Sound
```python
<Sound> = pg.mixer.Sound(<path/file/bytes>) # WAV file or bytes/array of signed shorts.
<Sound>.play/stop() # Also <Sound>.set_volume(<float>).
<Sound>.play/stop() # Also set_volume(<float>), fadeout(msec).
```

### Basic Mario Brothers Example
Expand Down Expand Up @@ -3373,7 +3373,7 @@ c 7 8 6
<GB> = <DF>.groupby(column_key/s) # Splits DF into groups based on passed column.
<DF> = <GB>.apply(<func>) # Maps each group. Func can return DF, Sr or el.
<GB> = <GB>[column_key] # Single column GB. All operations return a Sr.
<Sr> = <GB>.size() # A Sr of group sizes. Keys are group "names".
<Sr> = <GB>.size() # A Sr of group sizes. Same keys as get_group().
```

#### GroupBy — Aggregate, Transform, Map:
Expand Down
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