On 2016-10-02, nicolasessisbre...@gmail.com <nicolasessisbre...@gmail.com>: > **How does this compare to Python+Numpy? > **How much faster is Fython, and what are the restrictions on the > **Python code? > > Python+Numpy allows easy processing of vector, but there is a limit to > how much user-defined logic can be used with Numpy. For example, > operating on three different arrays to do something like > > if x[i] > 0 : > temp = get_value( y[i] ) > > if temp > 0: > z[i] = another_operation( z[i] ) > > may require three different Numpy calls. > With Fython, the if statements and the loop around them is directly > compiled to machine code.
> Fython speed is the same as Fortran speed. > > In some applications, I get a speed-up of 100 compared to Cython, and > a speed-up of 10 compared to C. > > I'm not a Cython nor a C expert, and I know that with some good > compiler flags, one may make the performance of these two languages > similar two Fortran. The advantage of Fython is that everything is > tune out-of-box because of its connection to Fortran. > > There is no restriction on the Python code. > Once a Fython program is avalaible, Python can throw any scalar or > Numpy array at it. > > **whether Fython is pass by reference (Fortran) or value > **and then there's the 'little' matter of one-based (Fortran) or > **zero-based (python) arrays? > > Fython is passed by reference, so that any modification made to a > variable in Fython is propagated back to Python. > > Fython follows Fortran syntax and is one-based by default. > This doesn't give any interop problem with Python, because what > matters is to know the pointer to the first element of an array, and > Fython knows it. > > For the programmer convenience, like Fortran, Fython allows the choice > between one-based and zero-based indexing at array declaration. Thank you! it sounds very interesting indeed, particularly for those of us with a substantial Fortran code base which needs to be updated. Please keep us posted on your progress! -- https://mail.python.org/mailman/listinfo/python-list
