==========================
Numpy Support in *numba*
==========================
One objective of *numba* is having a seamless integration with *NumPy*. *NumPy* arrays provide
an efficient storage method for homogeneous sets if data. *NumPy* dtypes provide type information
useful when compiling, and the regular, structured storage of potentially large amounts of data
in memory provides an ideal memory layout for code generation. *numba* excels at generating code
that executes on top of *NumPy* arrays.
*NumPy* support in Numba comes in many forms:
* *numba* understands *NumPy* ufuncs and is able to generate equivalent native code for many of them.
* *NumPy* arrays are directly supported in *numba*. Access to *Numpy* arrays is very efficient, as indexing is lowered to memory accessing when possible.
* *numba* is able to generate ufuncs/gufuncs. This means that it is possible to implement ufuncs/gufuncs within Python, getting speeds comparable to that of ufuncs/gufuncs implemented in C extension modules using the NumPy C API.
Supported ufuncs
================
One objective on *numba* is having all the standard ufuncs in NumPy understood by numba. When a supported ufunc is found when compiling a function, *numba* maps the ufunc to equivalent native code. This allows the use of those ufuncs in *numba* code that gets compiled in no-python mode.
Limitations
-----------
Right now support for ufuncs is quite limited in no-python mode. Meaning that only a selection of the ufuncs work in no-python mode.
Also, in its current implementation ufuncs working on arrays will only compile in no-python mode if the output is explicit (the output array is passed as second argument). Note that this limitation does not apply when applied to scalars
Following is a list of the different *NumPy* ufuncs that *numba* is aware of, sorted in the same way as in the *NumPy* documentation.
Math operations
---------------
============== ============= ===========
UFUNC MODE
-------------- --------------------------
name python-mode no-python
============== ============= ===========
add Yes Yes
subtract Yes Yes
multiply Yes Yes
divide Yes Yes
logaddexp Yes Yes
logaddexp2 Yes Yes
true_divide Yes Yes
floor_divide Yes Yes
negative Yes Yes
power Yes Yes
remainder Yes No
mod Yes No
fmod Yes No
abs Yes Yes
absolute Yes Yes
fabs Yes Yes
rint Yes Yes
sign Yes Yes
conj Yes No
exp Yes Yes
exp2 Yes Yes
log Yes Yes
log2 Yes Yes
log10 Yes Yes
expm1 Yes Yes
log1p Yes Yes
sqrt Yes Yes
square Yes No
reciprocal Yes No
conjugate Yes No
============== ============= ===========
Trigonometric functions
-----------------------
============== ============= ===========
UFUNC MODE
-------------- --------------------------
name python-mode no-python
============== ============= ===========
sin Yes Yes
cos Yes Yes
tan Yes Yes
arcsin Yes Yes
arccos Yes Yes
arctan Yes Yes
arctan2 Yes Yes
hypot Yes Yes
sinh Yes Yes
cosh Yes Yes
tanh Yes Yes
arcsinh Yes Yes
arccosh Yes Yes
arctanh Yes Yes
deg2rad Yes Yes
rad2deg Yes Yes
degrees Yes Yes
radians Yes Yes
============== ============= ===========
Bit-twiddling functions
-----------------------
============== ============= ===========
UFUNC MODE
-------------- --------------------------
name python-mode no-python
============== ============= ===========
bitwise_and Yes No
bitwise_or Yes No
bitwise_xor Yes No
bitwise_not Yes No
invert Yes No
left_shift Yes No
right_shift Yes No
============== ============= ===========
Comparison functions
--------------------
============== ============= ===========
UFUNC MODE
-------------- --------------------------
name python-mode no-python
============== ============= ===========
greater Yes No
greater_equal Yes No
less Yes No
less_equal Yes No
not_equal Yes No
equal Yes No
logical_and Yes No
logical_or Yes No
logical_xor Yes No
logical_not Yes No
maximum Yes No
minimum Yes No
fmax Yes No
fmin Yes No
============== ============= ===========
Floating functions
------------------
============== ============= ===========
UFUNC MODE
-------------- --------------------------
name python-mode no-python
============== ============= ===========
isfinite Yes No
isinf Yes No
isnan Yes No
signbit Yes No
copysign Yes Yes
nextafter Yes No
modf Yes No
ldexp Yes* No
frexp Yes No
floor Yes Yes
ceil Yes Yes
trunc Yes Yes
spacing Yes No
============== ============= ===========
\* not supported on windows 32 bit