On Tue, Nov 6, 2018 at 8:26 AM Foad Sojoodi Farimani <f.s.farim...@gmail.com> wrote: > > Dear Mark, > > Thanks for the reply. I will write in between your lines: > > On Tue, Nov 6, 2018 at 6:11 AM Mark Harfouche <mark.harfou...@gmail.com> > wrote: >> >> Foad, >> >> Visualizing data is definitely a complex field. I definitely feel your pain. > > I have actually been using numpy for a couple of years without noticing these > issues. recently I have been trying to encourage my collogues to move from > MATLAB to Python and also prepare some workshops for PhD network of my > university. >> >> Printing your data is but one way of visualizing it, and probably only >> useful for very small and constrained datasets. > > well actually it can be very useful. Consider Pandas .head() and .tail() > methods or Sympy's pretty printing functionalities. for bigger datasets the > function can get the terminals width and height and then based on the input > (U(n),D(n),L(n),R(n),UR(n,m),UL(n,m),DR(n,m),DL(n,m)) display what can be > shown and put horizontal 3-dots \u2026 … or vertical/inclined ones. Or id it > is Jupyter then one can use Markdown/LaTeX for pretty printing or even HTML > to add sliders as suggested by Eric. >> >> Have you looked into set_printoptions to see how numpy’s existing >> capabilities might help you with your visualization? > > This is indeed very useful. specially the threshold option can help a lot > with adjusting the width. but only for specific cases. >> >> The code you showed seems quite good. I wouldn’t worry about performance >> when it comes to functions that will seldom be called in tight loops. > > Thanks but I know it is very bad: > > it does not work properly for floats > it only works for 1D and 2D > there can be some recursive function I believe. >> >> As you’ll learn more about python and numpy, you’ll keep expanding it to >> include more use cases. >> For many of my projects, I create small submodules for visualization >> tailored to the specific needs of the particular project. >> I’ll try to incorporate your functions and see how I use them. > > Thanks a lot. looking forwards to your feedback >> >> Your original post seems to have some confusion about C Style vs F Style >> ordering. I hope that has been resolved. > > I actually came to the conclusion that calling it C-Style or F-Style or maybe > row-major column-major are bad practices. Numpy's ndarrays are not > mathematical multidimensional arrays but Pythons nested, homogenous and > uniform lists. it means for example 1, [1], [[1]] and [[[1]]] are all > different, while in all other mathematical languages out there (including > Sympy's matrices) they are the same.
I'm probably missing your point, because I don't understand your claim. Mathematically speaking, 1 and [1] and [[1] and [[[1]]] are different objects. One is a scalar, the second is an element of R^n with n=1 which is basically a scalar too from a math perspective, the third one is a 2-index object (an operator acting on R^1), the last one is a three-index object. These are all mathematically distinct. Furthermore, row-major and column-major order are a purely technical detail describing how the underlying data that is being represented by these multidimensional arrays is laid out in memory. So C/F-style order and the semantics of multidimensional arrays, at least as I see it, are independent notions. András _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@python.org https://mail.python.org/mailman/listinfo/numpy-discussion
