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Personally, matlab drives me absolutely up the wall when it comes to ANYTHING other that flipping big matricies around. As a domain-specific tool for linear al

Personally, matlab drives me absolutely up the wall when it comes to ANYTHING other that flipping big matricies around. As a domain-specific tool for linear algebra, I certainly prefer it over R, but as a general purpose tool it makes me want to pull my own teeth out. It's just not designed to make good pipeline tools that are maintainable, easily tested, and easily refactored, and never was. Its ability to handle things like "easy and sensible string and path manipulations" are ... rudimentary, at best, and a weird pastiche of C, fortran, java, and whatever else language was faddish when that feature was added. I have more or less one real annoyance with the technical content of matlab. (One-indexing i can live with): size([1]) ans = [1 1] which is flatly wrong, and numpy gets it right: In[0] np.array([1]).shape Out[0] (1,) Python is actually a general purpose language which has a mature scientific stack, and i feel more secure in my numerical computations there because i can have a robust test suite and command line entry points into my code that increase my confidence that my code's doing what i think it should be, and makes it easy to use. Packaging is more or less a coin-flip. Python packaging is a giant faff; matlab packaging is nonexistent (you have to vendor every dependency yourself) and expensive (your users have to shell out for the toolboxes you use, and/or have the MCR installed and can't edit your code). I'll maintain matlab when i have to, but i don't enjoy it very much.

commandlinefan 7y ago
Yeah, I was more than a little surprised to see his perspective - I thought for sure he was going to rave about Julia, pick on Python a little, and skewer Matlab. My graduate thesis advisor forced me to use Matlab to do all of my master’s thesis work, and I found it to be about the most frustrating environment possible, at least for any actual programming. I’m a little shocked to read that anybody uses Matlab outside of a pure academic environment… I guess I just don’t work on sophisticated enough projects?
- scott_s 7y ago
  The author of this post is in academia, so Matlab outside of academia may be as rare as you think.
  - Ragib_Zaman 7y ago
    I know of a few major trading firms that use MATLAB for a lot of their analysis. In many companies that hire engineers they also often use MATLAB as it's sufficient for what they need those engineers to do (and programmers at those companies use different languages), and many engineers come out of their degree feeling most comfortable with MATLAB for scientific computation.
  - galangalalgol 7y ago
    it is widely used in the rf signal processing community. communications, radar, that sort of thing
    - markmark 7y ago
      That's where I used it, although it was a while ago now. Processing results from EMI/EMC testing.
  - 6thaccount2 7y ago
    I think it is actually prevalent in a lot of industry. They don't make a lot of money off academia with those ~$30 student licenses.
    - analog31 7y ago
      Historically, the free or cheap student licenses were believed to pay them back when those students moved into industry and were inclined to install what they were familiar with. There's still a lot of MATLAB in college teaching curricula. Part of when I help on-board newly graduated colleagues (typically engineers and scientists, not hired as programmers) is to reassure them that they can get a MATLAB license if will help them get productive quickly. This has happened once or twice. Many of them never bother, as they get busy enough with CAD and basic design work, that they don't really find a use for scientific computation. But to an increasing extent, they're willing to make the hop to Python, possibly just because it's a popular buzzword, but in any event, they are able to get themselves up to speed pretty quickly.
- im_down_w_otp 7y ago
  It's extremely popular in control engineering domains. You would find it an impossible task to track down an automobile manufacturer or a platform level supplier which doesn't leverage Matlab & Simulink all over the place.
- rthomas6 7y ago
  People in my place of work love it for DSP algorithms.
fireattack 7y ago
>which is flatly wrong Why is it wrong? Edit: typo
- 3JPLW 7y ago
  In and of itself, it's not wrong. Where it goes sideways is how Matlab chooses to allow matrix operations against these 1x1 matrices that should otherwise fail, how Matlab chooses to iterate (over columns, unless it's a "row-vector"), and how Matlab chooses to define length (the max dimension). Amusingly this also leads to things like x = 1 x(end+1) = 2 x == [1 2]
  - tnecniv 7y ago
    I don't see how any of those behaviors are wrong. It's just a standard that MATLAB elects to follow.
- hprotagonist 7y ago
  a 1-tensor is not a 2-tensor, and scalars have no area. matlab: size(1) ans = [1,1] python: In[0]: np.array(1).shape Out[0]: () 0-tensors are not 2-tensors, either. You can read matlab's result as "scalars are matricies that have one row and one column", and that's nonsense -- matlab effectively lacks a scalar numeric type; under the covers, everything is a matrix.
  - kgwgk 7y ago
    Arrays are not tensors (except when they are, of course). If you want to talk about (n-dimensional) arrays of numbers why wouldn’t the word “array” be enough?
    - hprotagonist 7y ago
      in the nomenclature i’m used to, scalars, vectors, and matrices are all special cases of tensors. ( they have rank 0,1, and 2 respectively). what numpy calls it is more or less moot.
nimrody 7y ago
One behavior I like about Matlab is that functions are functions. Arguments are passed by value and there's no way a function can modify its arguments (well, except perhaps objects which are less common). Matlab will try to optimize and avoid a copy if the function does not modify the argument. Matlab is also (sometimes) smart enough so that A=f(A) will modify A in place instead of making a copy. This is what I expect from a math oriented language. Maintain the illusion of referential transparency but optimize under the hood if possible. Also Matlab has a reasonable JIT compiler. And a good debugger. I no longer use Matlab but it is a very productive environment for scientific computing (simulations, exploration).
- bobbylarrybobby 7y ago
  Many numpy functions have an `inplace` (or maybe there’s an underscore there?) argument that tells whether to perform the operation in place or return a new array.
  - newen 7y ago
    It's completely arbitrarily whether a numpy function or method modifies the array or not. No way to tell except documentation or trying it out.
enriquto 7y ago
> (...) ANYTHING other that flipping big matricies around. but... what else is there, in life? Flipping big matrices around is nearly everything I do, and the python stuff seems too cumbersome for me to bother.
- cfusting 7y ago
  What kind of flipping are you talking about? I can transpose a matrix in numpy with X.T. What is cumbersome about this?
  - enriquto 7y ago
    In python, I hate hate hate having to do import numpy import scipy.sparse import scipy.sparse.linalg just to begin writing something. You cannot create a literal array without calling a function. You cannot concatenate arrays without calling a function, and moreover this function has a different name depending on whether your arrays are full or sparse. The @ notation for matrix products is horrendous (and .dot is even worse). Arrays are not first-class objects of the language, and you have to use an external library. This is more infuriating by the fact that other, more complex data structures like dictionaries or strings are natively supported, even if they are mostly useless for numerical computation. Compare the clean matrix flipping in octave z = [ kron(speye(rows(y)), x) ; kron(y, speye(cols(x))) ] to the python monstrosity z = scipy.sparse.vstack([ scipy.sparse.kron(scipy.sparse.eye(y.shape[0]), x), scipy.sparse.kron(y, scipy.sparse.eye(x.shape[1])) ])
    - mlevental 7y ago
      lol don't blame the tools for your ignorance of them from scipy.sparse import eye, kron from scipy.spare import vstack as vs z = vs([ kron(eye(y.shape[0]), x), kron(y, eye(x.shape[1])) ])
      - enriquto 7y ago
        It's exactly the same thing that I wrote, isn't it? The thing that kills my soul is the need for the "vs" function. Why aren't the symbols [] not enough ?
deleted 7y ago
[deleted]

commandlinefan 7y ago

Yeah, I was more than a little surprised to see his perspective - I thought for sure he was going to rave about Julia, pick on Python a little, and skewer Matlab. My graduate thesis advisor forced me to use Matlab to do all of my master’s thesis work, and I found it to be about the most frustrating environment possible, at least for any actual programming. I’m a little shocked to read that anybody uses Matlab outside of a pure academic environment… I guess I just don’t work on sophisticated enough projects?

scott_s 7y ago
The author of this post is in academia, so Matlab outside of academia may be as rare as you think.
- Ragib_Zaman 7y ago
  I know of a few major trading firms that use MATLAB for a lot of their analysis. In many companies that hire engineers they also often use MATLAB as it's sufficient for what they need those engineers to do (and programmers at those companies use different languages), and many engineers come out of their degree feeling most comfortable with MATLAB for scientific computation.
- galangalalgol 7y ago
  it is widely used in the rf signal processing community. communications, radar, that sort of thing
  - markmark 7y ago
    That's where I used it, although it was a while ago now. Processing results from EMI/EMC testing.
- 6thaccount2 7y ago
  I think it is actually prevalent in a lot of industry. They don't make a lot of money off academia with those ~$30 student licenses.
  - analog31 7y ago
    Historically, the free or cheap student licenses were believed to pay them back when those students moved into industry and were inclined to install what they were familiar with. There's still a lot of MATLAB in college teaching curricula. Part of when I help on-board newly graduated colleagues (typically engineers and scientists, not hired as programmers) is to reassure them that they can get a MATLAB license if will help them get productive quickly. This has happened once or twice. Many of them never bother, as they get busy enough with CAD and basic design work, that they don't really find a use for scientific computation. But to an increasing extent, they're willing to make the hop to Python, possibly just because it's a popular buzzword, but in any event, they are able to get themselves up to speed pretty quickly.
im_down_w_otp 7y ago
It's extremely popular in control engineering domains. You would find it an impossible task to track down an automobile manufacturer or a platform level supplier which doesn't leverage Matlab & Simulink all over the place.
rthomas6 7y ago
People in my place of work love it for DSP algorithms.

fireattack 7y ago

>which is flatly wrong Why is it wrong? Edit: typo

3JPLW 7y ago
In and of itself, it's not wrong. Where it goes sideways is how Matlab chooses to allow matrix operations against these 1x1 matrices that should otherwise fail, how Matlab chooses to iterate (over columns, unless it's a "row-vector"), and how Matlab chooses to define length (the max dimension). Amusingly this also leads to things like x = 1 x(end+1) = 2 x == [1 2]
- tnecniv 7y ago
  I don't see how any of those behaviors are wrong. It's just a standard that MATLAB elects to follow.
hprotagonist 7y ago
a 1-tensor is not a 2-tensor, and scalars have no area. matlab: size(1) ans = [1,1] python: In[0]: np.array(1).shape Out[0]: () 0-tensors are not 2-tensors, either. You can read matlab's result as "scalars are matricies that have one row and one column", and that's nonsense -- matlab effectively lacks a scalar numeric type; under the covers, everything is a matrix.
- kgwgk 7y ago
  Arrays are not tensors (except when they are, of course). If you want to talk about (n-dimensional) arrays of numbers why wouldn’t the word “array” be enough?
  - hprotagonist 7y ago
    in the nomenclature i’m used to, scalars, vectors, and matrices are all special cases of tensors. ( they have rank 0,1, and 2 respectively). what numpy calls it is more or less moot.

nimrody 7y ago

One behavior I like about Matlab is that functions are functions. Arguments are passed by value and there's no way a function can modify its arguments (well, except perhaps objects which are less common). Matlab will try to optimize and avoid a copy if the function does not modify the argument. Matlab is also (sometimes) smart enough so that A=f(A) will modify A in place instead of making a copy. This is what I expect from a math oriented language. Maintain the illusion of referential transparency but optimize under the hood if possible. Also Matlab has a reasonable JIT compiler. And a good debugger. I no longer use Matlab but it is a very productive environment for scientific computing (simulations, exploration).

bobbylarrybobby 7y ago
Many numpy functions have an `inplace` (or maybe there’s an underscore there?) argument that tells whether to perform the operation in place or return a new array.
- newen 7y ago
  It's completely arbitrarily whether a numpy function or method modifies the array or not. No way to tell except documentation or trying it out.

enriquto 7y ago

> (...) ANYTHING other that flipping big matricies around. but... what else is there, in life? Flipping big matrices around is nearly everything I do, and the python stuff seems too cumbersome for me to bother.

cfusting 7y ago
What kind of flipping are you talking about? I can transpose a matrix in numpy with X.T. What is cumbersome about this?
- enriquto 7y ago
  In python, I hate hate hate having to do import numpy import scipy.sparse import scipy.sparse.linalg just to begin writing something. You cannot create a literal array without calling a function. You cannot concatenate arrays without calling a function, and moreover this function has a different name depending on whether your arrays are full or sparse. The @ notation for matrix products is horrendous (and .dot is even worse). Arrays are not first-class objects of the language, and you have to use an external library. This is more infuriating by the fact that other, more complex data structures like dictionaries or strings are natively supported, even if they are mostly useless for numerical computation. Compare the clean matrix flipping in octave z = [ kron(speye(rows(y)), x) ; kron(y, speye(cols(x))) ] to the python monstrosity z = scipy.sparse.vstack([ scipy.sparse.kron(scipy.sparse.eye(y.shape[0]), x), scipy.sparse.kron(y, scipy.sparse.eye(x.shape[1])) ])
  - mlevental 7y ago
    lol don't blame the tools for your ignorance of them from scipy.sparse import eye, kron from scipy.spare import vstack as vs z = vs([ kron(eye(y.shape[0]), x), kron(y, eye(x.shape[1])) ])
    - enriquto 7y ago
      It's exactly the same thing that I wrote, isn't it? The thing that kills my soul is the need for the "vs" function. Why aren't the symbols [] not enough ?

deleted 7y ago

[deleted]