ulab – Manipulate numeric data similar to numpy

ulab is a numpy-like module for micropython, meant to simplify and speed up common mathematical operations on arrays. The primary goal was to implement a small subset of numpy that might be useful in the context of a microcontroller. This means low-level data processing of linear (array) and two-dimensional (matrix) data.

ulab is adapted from micropython-ulab, and the original project’s documentation can be found at https://micropython-ulab.readthedocs.io/en/latest/

ulab is modeled after numpy, and aims to be a compatible subset where possible. Numpy’s documentation can be found at https://docs.scipy.org/doc/numpy/index.html

ulab._DType

ulab.int8, ulab.uint8, ulab.int16, ulab.uint16, ulab.float or ulab.bool

ulab._float

Type alias of the bulitin float

ulab._bool

Type alias of the bulitin bool

ulab._Index
class ulab.array(values: Union[array, Iterable[Union[_float, _bool, Iterable[Any]]]], *, dtype: _DType = ulab.float)

1- and 2- dimensional array

Parameters

The values sequence can either be another ~ulab.array, sequence of numbers (in which case a 1-dimensional array is created), or a sequence where each subsequence has the same length (in which case a 2-dimensional array is created).

Passing a ulab.array and a different dtype can be used to convert an array from one dtype to another.

In many cases, it is more convenient to create an array from a function like zeros or linspace.

ulab.array implements the buffer protocol, so it can be used in many places an array.array can be used.

shape :Tuple[int, ...]

The size of the array, a tuple of length 1 or 2

size :int

The number of elements in the array

itemsize :int

The size of a single item in the array

strides :Tuple[int, ...]

Tuple of bytes to step in each dimension, a tuple of length 1 or 2

copy(self) → ulab.array

Return a copy of the array

dtype(self) → _DType

Returns the dtype of the array

flatten(self, *, order: str = 'C') → ulab.array
Parameters

order – Whether to flatten by rows (‘C’) or columns (‘F’)

Returns a new ulab.array object which is always 1 dimensional. If order is ‘C’ (the default”, then the data is ordered in rows; If it is ‘F’, then the data is ordered in columns. “C” and “F” refer to the typical storage organization of the C and Fortran languages.

reshape(self, shape: Tuple[int, …]) → ulab.array

Returns an array containing the same data with a new shape.

sort(self, *, axis: Optional[int] = 1) → None
Parameters

axis – Whether to sort elements within rows (0), columns (1), or elements (None)

tobytes(self) → bytearray

Return the raw data bytes in the array

transpose(self) → ulab.array

Swap the rows and columns of a 2-dimensional array

__add__(self, other: Union[array, _float]) → ulab.array

Adds corresponding elements of the two arrays, or adds a number to all elements of the array. If both arguments are arrays, their sizes must match.

__radd__(self, other: _float) → ulab.array
__sub__(self, other: Union[array, _float]) → ulab.array

Subtracts corresponding elements of the two arrays, or subtracts a number from all elements of the array. If both arguments are arrays, their sizes must match.

__rsub__(self, other: _float) → ulab.array
__mul__(self, other: Union[array, _float]) → ulab.array

Multiplies corresponding elements of the two arrays, or multiplies all elements of the array by a number. If both arguments are arrays, their sizes must match.

__rmul__(self, other: _float) → ulab.array
__div__(self, other: Union[array, _float]) → ulab.array

Multiplies corresponding elements of the two arrays, or divides all elements of the array by a number. If both arguments are arrays, their sizes must match.

__rdiv__(self, other: _float) → ulab.array
__pow__(self, other: Union[array, _float]) → ulab.array

Computes the power (x**y) of corresponding elements of the the two arrays, or one number and one array. If both arguments are arrays, their sizes must match.

__rpow__(self, other: _float) → ulab.array
__inv__(self) → ulab.array
__neg__(self) → ulab.array
__pos__(self) → ulab.array
__abs__(self) → ulab.array
__len__(self) → int
__lt__(self, other: Union[array, _float]) → ulab.array

Return self<value.

__le__(self, other: Union[array, _float]) → ulab.array

Return self<=value.

__gt__(self, other: Union[array, _float]) → ulab.array

Return self>value.

__ge__(self, other: Union[array, _float]) → ulab.array

Return self>=value.

__iter__(self) → Union[Iterator[array], Iterator[_float]]
__getitem__(self, index: _Index) → Union[array, _float]

Retrieve an element of the array.

__setitem__(self, index: _Index, value: Union[array, _float]) → None

Set an element of the array.

ulab._ArrayLike

ulab.array, List[float], Tuple[float] or range

ulab.int8 :_DType

Type code for signed integers in the range -128 .. 127 inclusive, like the ‘b’ typecode of array.array

ulab.int16 :_DType

Type code for signed integers in the range -32768 .. 32767 inclusive, like the ‘h’ typecode of array.array

ulab.float :_DType

Type code for floating point values, like the ‘f’ typecode of array.array

ulab.uint8 :_DType

Type code for unsigned integers in the range 0 .. 255 inclusive, like the ‘H’ typecode of array.array

ulab.uint16 :_DType

Type code for unsigned integers in the range 0 .. 65535 inclusive, like the ‘h’ typecode of array.array

ulab.bool :_DType

Type code for boolean values

ulab.get_printoptions() → Dict[str, int]

Get printing options

ulab.set_printoptions(threshold: Optional[int] = None, edgeitems: Optional[int] = None) → None

Set printing options

ulab.ndinfo(array: ulab.array) → None
ulab.arange(stop: _float, step: _float = 1, *, dtype: _DType = ulab.float) → ulab.array
ulab.arange(start: _float, stop: _float, step: _float = 1, *, dtype: _DType = ulab.float) → ulab.array

Return a new 1-D array with elements ranging from start to stop, with step size step.

ulab.concatenate(arrays: Tuple[ulab.array], *, axis: int = 0) → ulab.array

Join a sequence of arrays along an existing axis.

ulab.diag(a: ulab.array, *, k: int = 0) → ulab.array

Return specified diagonals.

ulab.eye(size: int, *, M: Optional[int] = None, k: int = 0, dtype: _DType = ulab.float) → ulab.array

Return a new square array of size, with the diagonal elements set to 1 and the other elements set to 0.

ulab.full(shape: Union[int, Tuple[int, …]], fill_value: Union[_float, _bool], *, dtype: _DType = ulab.float) → ulab.array

Return a new array of the given shape with all elements set to 0.

ulab.linspace(start: _float, stop: _float, *, dtype: _DType = ulab.float, num: int = 50, endpoint: _bool = True, retstep: _bool = False) → ulab.array

Return a new 1-D array with num elements ranging from start to stop linearly.

ulab.logspace(start: _float, stop: _float, *, dtype: _DType = ulab.float, num: int = 50, endpoint: _bool = True, base: _float = 10.0) → ulab.array

Return a new 1-D array with num evenly spaced elements on a log scale. The sequence starts at base ** start, and ends with base ** stop.

ulab.ones(shape: Union[int, Tuple[int, …]], *, dtype: _DType = ulab.float) → ulab.array

Return a new array of the given shape with all elements set to 1.

ulab.zeros(shape: Union[int, Tuple[int, …]], *, dtype: _DType = ulab.float) → ulab.array

Return a new array of the given shape with all elements set to 0.

ulab.frombuffer(buffer: ReadableBuffer, dtype: _DType = ulab.float, count: int = - 1, offset: int = 0) → ulab.array

Interpret a buffer as a 1-dimensional array.