+1 Numpy also behaves the way Mike is suggesting here. imran On Fri, Jul 28, 2017 at 5:21 PM, Nakul Jindal wrote: > +1 to Mike & Deron. > > Two other languages/packages that behave like this: > R : http://www.r-tutor.com/r-introduction/matrix > Octave : > https://www.gnu.org/software/octave/doc/interpreter/Index-Expressions.html > > > -Nakul > > > > > On Fri, Jul 28, 2017 at 4:03 PM, Deron Eriksson > wrote: > > > Thank you Mike for bringing this up. To me, this definitely makes sense > at > > the user (DML) level. > > > > For a Java-style pseudocode example, currently we require the user to do > > the following: > > int[][] m = int[][]{1,2,3,4}; > > int[][] n = m[0][0]; > > int x = (int) n; > > > > I feel the following would be more 'natural': > > int[][] m = int[][]{1,2,3,4}; > > int x = m[0][0]; > > > > If a user asks for a specific cell (and not a range) in DML code, I think > > the user clearly wants a value and not a matrix that the user needs to > cast > > via as.scalar. > > > > Deron > > > > > > > > On Fri, Jul 28, 2017 at 3:41 PM, wrote: > > > > > Currently, non-range matrix indexing, such as `X[1,2]`, returns a 1x1 > > > matrix in SystemML rather than a single scalar value. This is > > inconsistent > > > with mathematical semantics, and with array indexing semantics of any > > major > > > language, thus leading to confusion for users. > > > > > > I would like to propose that non-range indexing at the language level, > > > such as `X[1,2]`, should return a single scalar value, and range > indexing > > > of any kind at the language level, including the trivial example > > > `X[1:1,2:2]`, should return a matrix. This would lead to clear > semantics > > > that are consistent with mathematics and language array indexing, thus > > > preventing user confusion. Additionally, these are the semantics that > > the > > > NumPy project uses. > > > > > > Interested to hear thoughts from the rest of the community! > > > > > > -Mike > > > > > > -- > > > > > > Mike Dusenberry > > > GitHub: github.com/dusenberrymw > > > LinkedIn: linkedin.com/in/mikedusenberry > > > > > > Sent from my iPhone. > > > > > > > > >