What is missing from MATLAB?

I'm curious, is there something you wish to do with MATLAB but you can't, maybe something you can do with other similar software but can't with MATLAB?

For new entries, please use the follow-up thread here. Please do not post new answers in this thread.

[Nitin Chauhan]

Yes there one thing. I am not able to find out the induction machine model with stator isolated windings available with all the six stator winding terminals access.

[Walter Roberson]

But can you do that in other similar software, Nitin?

[Andrew P]

Yes, 6 terminal induction machines are possible in other software. PSCAD has a 6 terminal induction machine model, although I don't think it's part of their standard library.

[Walter Roberson]

Huh, PSCAD turns out to be made by an organization on the first north-south road over from here. :-)

[Jeff Owen]

When inserting text into a figure, Matlab gives 'left, center, or right' as options for horizontal placement. Why not 'top, middle, and bottom'? I have a vector of text strings, the top of which I want to position at the top of the graph, but the placement is automatically 'middle'. The length of the vector changes from time to time. It would be clumsy to have to re-calculate the placement coordinates based on the length of the vector. Easier if I could just say 'top'.

[Jeff Owen]

Oops, turns out it is there. I just tried 'VerticalAlignment','top' and it works. Should be included in the help file associated with 'text'?

[Stephen23]

"... horizontal placement. Why not 'top, middle, and bottom'?"

Because top, middle, and bottom are vertical alignment, not horizontal alignment.

"Should be included in the help file associated with 'text'?"

In the help page: "For a full list, see Text Properties", which takes you to the page describing all of properties of the text object. These are listed in their own dedicated help page (just like with every other graphics object).

Answer 1

[Walter Roberson]

The result of every expression should be further indexable by all of the index methods. This includes not only function calls but literals or expressions: e.g.,

(1:3:20)(K:K+1)

or

[struct('hello',A+5),B].hello

[Andrew Newell]

Doesn't this just make code more cryptic?

[Oleg Komarov]

This makes code a lot more cryptic...

[Walter Roberson]

It is pretty standard for object-oriented languages, and has long existed in (e.g.) C. It works in Maple too. These days what is confusing is a language where for a small number of expression types it does _not_ work -- especially since half of the battle is historical parsing reasons about procedures with no arguments.

[Matt Tearle]

It certainly *can* make for cryptic code, but so can virtually any construct. This is a construct I've wanted a few times, and I don't think it would have been particularly cryptic in those cases.... well, not if I'd commented my code, at least... Oh. Right.

[Paulo Silva]

Walter I accepted your answer because it was the most voted and I agree with both suggestions, lets make Matlab even better.

[David Goldsmith]

I want this bad: I might not use it much in m-files (then again I might), but I want it _all the time_ in interactive mode, e.g., when I'm debugging!

[Irl]

A nice way to implement this without a very dangerous extension of existing syntax would be a function that simply indexes into an array, kind of like getfield: my wished-for function, call it getelement, would do this:

getelement([1 2 3;4 5 6],[2 3])

returns 6, i.e., operates like

[1 2 3;4 5 6](2,3)

[Raphael Cautain]

Several old languages - not solely functional languages - have already this functionality : C, IDL ... The present situation is just a restriction, since the result is safely available in the interpreter. This extension would save memory.

@Irl : while waiting for this :

function output = getelement(expr, subs)
q = num2cell(subs);
output = expr(q{:});
end

[Walter Roberson]

Raphael, the extension would not actually save any memory, except for an entry in the name table. Everything else about the expression would be shared, due to the way "copy on write" works in MATLAB.

T = expression(); T(2,3)

does not take any more memory than expression()(2,3) would. T would be created as essentially a pointer to the memory that describes the type and array dimensions of the expression and the location of the memory block, so doing the assignment only takes enough memory for the name "T" and the pointer.

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

[timo]

yay

[MINATI]

Also in solving ode (BY bvp4c) if we take variation of any parameter in X-axis when previously f ' varies with x

Ref: https://in.mathworks.com/matlabcentral/answers/396548-how-to-plot-for-t0-5-y-axis-vs-nt-ranges-from-0-1-to-0-5-in-x-axis-where-alre

[Adam Danz]

I searched for this thread solely to add this recommendation only to find that not only has it already been added but is the most supported suggestion.

The use of literals in expressions has been available in Python and I disagree with some of the (8 year old) comments above that such practice would be cryptic. On the contrary, it's pretty intuitive what the following lines do:

n=3
[1,2,4,7,11,14,16,17](n)

% hypothetical ans:
% ans = 4

[Rik]

@Adam, I think we are almost there. The example given makes me shudder with the though of how novice users will misuse this to strive for more compact code instead of better readable code.

Your example makes sense, but that tends to be true for most constructs. Currently (R2019b) you can do this:

n=3;
if ~verLessThan('matlab','9.7')
    table([1,2,4,7,11,14,16,17]).Var1(n)
end

Edit:

I just tested this on R2015a, and it already works, despite the release notes suggesting otherwise. That very same release notes search suggest this isn't actually something new, but is actually something that was ostensibly removed in R2010a.

%both of these work in R2015a (and presumably most releases):
n=3;table([1,2,4,7,11,14,16,17]).Var1(n)
n=3;struct('Var1',[1,2,4,7,11,14,16,17]).Var1(n)
%the struct line does error on R13 (v6.5)

Answer 2

[Jan]

A long term supported version!

The current policy to fix bugs mainly by shipping a new release has the important drawback, that a new relase includes new bugs ever. If reliability is extremely important, e.g. for the prediction of the outcome of surgical operations for children, MATLAB is a fairly good choice, as long as a program runs only on the release it was developped on. I must be able to reproduce the results of a published medical study for 10 years. If such a study needs 5 years to measure the long term effects of a medical treatment, it is really unclear, if I can run MATLAB 2010b in the year 2025. Therefore MATLAB is actually not suitable for a long term study -- but there is a good argument to use it in spite of these facts: The alternatives are even worse.

[Doug Hull]

Have you tried compiling? This will lock down an executable.

[Jan]

Locking is not helpful: I can simply avoid installing (and buying) new Matlab releases to lock the current state. But when I compile my program, I suffer from two sources of bugs, which cannot be fixed: In my program *and* in the Matlab release.

Imagine an institute, which has very strict user-policies for security reasons and is still running e.g. Matlab 6.5 for compatibility reasons. Now the local admin found out, that this release is affected by the SPRINTF-bug, which allows to gain root privilegs. If the admin follows his contract, he has to forbid the usage of Matlab 6.5, such that I have to install the newer (and much better) Matlab release 2010b and need 3 month for checking all differences in the results to assure a certain level of reliability. After some month a new severe bug will appear, which will be fixed only by updating to a newer release. And after some month a new severe bug will appear...

[Robert Cumming]

I agree with this point, while compiling (or pcode) can "freeze/lockdown" code - what happens if you have to do some investigations into the internals of your code?

I work in the Aerospace industry and projects are expected to have lifecycle of 10's of years (think Boeing 747 entered service in the 60's and is still selling today). In certification, any data which is analysed/processed using any code must be re-produceable at any point in the the future - bugs and all!! ;)

So we have to keep a log of which version of Matlab was used and must be able to go back to that version if and when required.

[Horia]

Unfortunately, you have to accept the drawbacks of new releases:

Eg:I never arrived to use Photoshop CS4 Extended from within Matlab R2009b, and R2010B, all 64 bits;and I lost a lot of time trying to apply the solutions given by Mathworks, Adobe and forums. Everything works like a charm with 2011a,Photoshop CS5 Extended and the Intel C++ compiler (all, 64 bits).

I'm sure all this is commercial strategy.To use Robert Cumming's example:what would become the car industry if it worked like Boeing?

[Jan]

There is a new service pack for 2010b, although it is 2012 now. I do not have 2010b, such that I cannot download the SP2 and check the improvements. But I'm positively impressed by this special support activity!

I think it is worth to announce this update in public, because it increases the user's trust in the reliability of Matlab substantially.

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

[dpb]

Hadn't seen this previously until last activity link was adjacent...but it's still most apropos to real world.

Can't agree with Jan/Robert more -- in nuclear power generation field we were expected to keep similar abilities to reproduce safety-related calculations for "the life of the plant" which began as the 40-yr lifetime when applications were filed. Many of these plants are now well past that and have foreseeable futures extending another 20 years or more.

Hence, we were never able to use MATLAB for such because it wasn't stable.

Of course, it's impossible to now rerun old LIFE cross-section calculations on the Philco-3000 I ran in 1968, but at least we did have a traceable migration path.

"Geezer Alert!"

Until building inspector/fire marshall put end to it for possibly exceeding design floor loadings and the fire-safety issue, the entire outside halways of the office building were lined from one end to the other with metal shelves stacked full of "greenbar" folders of computer output. One overnight run would generate roughly 12-18" stack of printout, almost a hundred of us each doing that virtually every night added up to a lot of paper! Eventually they rented the old PigglyWiggly store and turned it into the repository for filing/retrieval identification before shipping them to the salt mines in Hutchinson, KS, for long term storage.

https://www.undergroundvaults.com/about-us/hutchinson/

http://www.kansastravel.org/hutchinson/kansasundergroundsaltmuseum2.htm

Answer 3

[Matt Fig]

Real pass by reference.

[Doug Hull]

Where does out current model not suffice?

[Peter O'Connor]

should just have an option to create matrices that act as if they were subclasses of handle (pointers).

ie a=rand(1,1000000); b=a; a(1)=2; takes a long time, a(1)~=b(1)

a=*rand(1,1000000); b=a; a(1)=2; would be fast, a(1)==b(1). this'd be practical if calling functions to modify, not copy, a large matrix.

[Malcolm Lidierth]

Peter

How about this?

classdef databucket < handle
 
 properties (Access='public')
 Bucket
 end
 
 methods
 
 function obj=databucket(data)
 obj.Bucket=data;
 return
 end
 
 function varargout=subsref(obj, varargin)
 varargout{1:nargout}=subsref(obj.Bucket, varargin{:});
 return
 end
 
 function varargout=subsasgn(obj, varargin)
 varargout{1:nargout}=subsasgn(obj.Bucket, varargin{:});
 return
 end
 
 end
 
end

I've created a set classes that do something like this using data on file, either memory mapped or accessed using low-level i/o so the "Bucket" can be many Gb without having them in memory all at once. With extra work to overload size, double etc and make X(:) a special case, these "nakhur" classes can be used anywhere a double precision array can be used in m-code.

[owr]

Malcolm, databucket is nice but an issue is that subsref in objects is much slower than in native arrays. Try this:

% Start Code
N = 100000;
d1 = randn(N,1);
d2 = randn(N,1);
db1 = databucket(d1);
db2 = databucket(d2);
dres = zeros(N,1);
dbres = zeros(N,1);
tic;
for i=1:N
 dres(i) = d1(i).*d2(i);
end
nativetime = toc
tic;
for i=1:N
 dbres(i) = db1(i).*db2(i);
end
objecttime = toc
% End code

In terms of the original question though, Ive managed fine without explicit pass by reference. But I can understand why one would want it.

Answer 4

[Doug Hull]

The most effective way to put in an enhancement request for MATLAB is shown here.

It is fine to discuss things, but this forum is not guaranteed to be seen by the right people. The above link is.

[Jan]

I suggest: Discuss at first here, forward the results afterwards.

[Michelle Hirsch]

I'm certainly watching the discussion! Jan's idea is a good one. You may want to mention if a particular suggestion happened to get lots of votes.

Thanks to all of you for your input.

[Julian]

Doug, may I ask how does one view/navigate/search the enhancement requests submitted this way? Mathworks.com search allows you to search Bug Reports (for example), but I could not see "enhancement requests". Thanks.

Answer 5

[Aurelien Queffurust]

What is missing in MATLAB?

Here are my two quick thoughts for today :

1) More choice in default uicontrols:

Currently , user interface controls include push buttons, toggle buttons, sliders, radio buttons, edit text controls, static text controls, pop-up menus, check boxes, and list boxes.

I would like to have more custom pushbuttons . I would like to be able to modify the borderwidth (like for uipanel) , to choose another form than rectangle or square like circle , triangle ... I really feel frustrated not to be able to build a GUI with such components . Currently the only thing I do to enhance the design of my softwares is to use CData to add icons ! I always try to find the best backgroundcolor for my GUI ...changing colors is possible but not the form/appearance of the uicontrols.

Except uitable which is quite new, I didn't find any major improvement to build GUI since many years.

2) Documentation in another language

What about a French doc ?!! Translating the doc in Japanese was possible , so doing the same thing in French should be also possible .

Aurélien

My Blog for MATLAB geeks

[Steven Lord]

App Designer, introduced in release R2016a, includes many additional components. Some of these may be of use to you; if there are others that you'd like to see included that aren't there, please submit an enhancement request with details about the components you want to see included.

[timo]

The tool is nice , but if more than 1000 lines of generated lines of code it crawls to a halt !

[Steven Lord]

That is a known issue captured in bug report 1376893.

[Steven Lord]

Bug report 1376893 was marked as fixed in release R2016b, and the Release Notes for MATLAB in both release R2017a and release R2017b say that loading apps in App Designer is faster.

[Steven Lord]

In release R2018b, the Release Notes has two entries relevant to this question:

• "Building Apps: Faster canvas interactions in App Designer"
• "Running Apps: Faster startup time for apps"

[Steven Lord]

1) The capability to create custom UI component classes was added in release R2020b and the ability to use them in App Designer was added in release R2021a. See the Release Notes for more information.

2) A subset of the documentation is available in French on the web in release R2021a.

Re: performance of App Designer: The Performance section of the release R2021a Release Notes lists several improvements related to graphics, UIs, and the Live Editor.

Answer 6

[Jan]

It would be very helpful, if the Mex-interface is completely documented. Especially the inplace write access to variables passed by reference is a holy secret - although it is possible already and would be much more efficient.

[Royi Avital]

+1

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

Answer 7

[Walter Roberson]

Graphic support for arbitrary unicode characters.

[Ian]

yes please! surely matlab should be unicode friendly by now!

[Walter Roberson]

(This has been added in more places, as of R2014b. If I understand correctly there are still a few places that cannot handle Unicode; some parts of Simulink, I think I read, and the TeX and LaTeX interpreters do not have Unicode support.)

[Walter Roberson]

I have been able to use unicode characters with TeX, but not with LaTeX.

Answer 8

[Walter Roberson]

Exposed documented serialization routines. Currently, to transmit Matlab variables to a different process, about the best method available is to save() to file, send the binary file, read the binary and write it to disk, and load() the variables.

Better methods must exist already for use with parallel processing, so it would help to expose and document them.

[Joan Puig]

I would love to see this implemented

[Ian]

I would really love to see this too, even if all we have access to is the byte stream result of save we could route somewhere else. Ideally there would be a defined intermediate format.

[Mike]

Yes, Something like this is needed.

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

Answer 9

[Oleg Komarov]

Anti-aliasing... MYAA

[Michael Johnston]

Yeah, it's kind of ridiculous that we need to go to the File Exchange to be able to produce reasonable looking figures. The figure export options in MATLAB are pretty weak because they're not WYSWIG... lots of trial and error and visits to File Exchange required to produce something that looks decent in a PDF.

[Walter Roberson]

(Anti-Aliasing was improved from R2014b or a release soon after that. I gather it still has some oddities as of R2016a.)

Answer 10

[Walter Roberson]

Programmatic layout routines. I had to create my own, one pass to shrink-wrap a control to the size it needs to hold the value(s), and the second pass to position the control relative to another control.

Exporting from GUIDE produces completely unmaintainable coordinates. It is not an option for producing maintainable software.

[Walter Roberson]

(App Designer is possibly a step in this direction; I have not looked at it much.)

[Steven Lord]

I'm not completely sure if this satisfies your needs, but we introduced a function uigridlayout in release R2018b that may help with laying out your app more easily.

[Walter Roberson]

Looks like that is for App Designer use.

[Image Analyst]

And AppDesigner is so cumbersome to use that I don't use it. I'd like to talk to the AppDesigner developers if I can and explain to them why it's not having quick adoption (from what I can see) and how we can improve it to a point where I can actually start using it. They probably think it's great. Well, it has promise but it's not great yet.

[Adam]

I tend to use the GUI Layout toolbox for this kind of thing.

[Steven Lord]

I've forwarded this particular answer to some of the people responsible for App Designer.

[Adam]

I would also agree with Image Analyst on App Designer. I like some aspects of it and the direction it promises, but I don't find it in any way usable, for numerous reasons, a few of which I've passed on, others I have probably forgotten as I haven't used it for quite a while now.

[Sulaymon Eshkabilov]

MATLAB's GUIDE has to be improved by cleaning up some automatically generated components of nested/subfunctions. It should have some explicit hints for users to ease the process of editing them w.r.t their designed GUI tools. Good luck.

[Rik]

@Sulaymon Eshkabilov Mathworks decided to improve on GUIDE by removing it. All templates (except blank) are already removed in R2021a, so I expect them to remove it completely in R2021b or R2022a.

For a more GUI-related discussion you may have look at this thread. If you have anything to add, feel free to comment there.

[Sulaymon Eshkabilov]

Thanks. I will definitely go over this issue to find out what novelties are introduced in 2021a as soon as I install it.

[Adam Danz]

From the documentation

https://www.mathworks.com/help/matlab/creating_guis/about-the-simple-guide-gui-example.html

Answer 11

[Ben Petschel]

1. Distinguishing variable from function names in M-Lint. To get around the current limitation, "declare" which names are variables and which are functions, e.g. with %#fdef and %#vdef statements somewhere after the help header. These could be generated automatically e.g. via a dialogue box that asks the user to tick the boxes as to which ambiguous names are which. It would be useful for detecting uninitialized variables and other common typos.

2. Allow pausing/monitoring/debugging calculations mid-flow, e.g. with a pause button, or breakpoints that can be added during program execution, or a variable monitor window that displays variable values in a given workspace while the function/script is running. Would be very useful for monitoring long calculations without killing them.

3. multiple-line anonymous functions, or allow function declarations in scripts.

4. function calls with named arguments and default values in the function definition, e.g. "function f(x=[],n=length(x))" and "f(n=1)".

[Walter Roberson]

Pausing state for examination without ruining the calculation would be beneficial!

[K E]

Yes, I have always wanted that myself.

[Steven Lord]

Release R2016a introduced a Pause button in the editor. Using it temporarily interrupts execution and enters debug mode. See the item in the Desktop section of the Release Notes for MATLAB for that release.

[Steven Lord]

As of release R2016b you can now define local functions inside of script files.

[Walter Roberson]

That is a good step towards solving a common problem (though one I probably would have solved by expanding the error message...), but I suspect that now more than ever people are going to be wanting to copy and paste entire scripts with functions to the command line.

[Steven Lord]

Release R2019b allows you to declare specific restrictions (and default values) for input arguments. See more in the Release Notes and the documentation page to which that note links.

Answer 12

[Walter Roberson]

An equivalent to the ?: operator, in which the unselected part does not get evaluated.

[Jan Rubak]

I've wished for the same, especially for use in anonymous functions.

[David Goldsmith]

"I've wished for the same" many times...

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

Answer 13

[Walter Roberson]

A way to return multiple outputs from a function in an expression context, without having to resort to using a separate assignment statement.

Even if at the beginning this only allowed selecting one output to return by discarding the leading N outputs, that would help .

This is functionality that cannot be written at the user level.

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

[dpb]

Does not Octave have at least some of this capability I think I recall seeing? I agree (and added my vote for the Answer previously); just ran into another case on a forum query the other day where temporary created for no other reason clutters up the workspace...

Answer 14

[Peter O'Connor]

ability to enter default inputs like in python as in function out=foo(bar,bar1='arr',bar2='yarr') ...

[Oleg Komarov]

I don't get it, does it mean that on the next call of foo, the second input will be automatically 'arr'?

[Walter Roberson]

foo(bar) would be treated as foo(bar,'arr','yarr')

foo(bar,bar1) would be treated as foo(bar,bar1,'yarr')

foo(bar,bar1,bar2) would have no default applied.

[Walter Roberson]

The best tool along these lines that I have ever seen was for DEC VAX VMS. The tool allowed one to construct conditional trees of argument processing, so that some arguments would only be expected (or given default value if missing) if other arguments were present, or so that it was possible to say that arguments were incompatible. The default values could vary depending upon which switches were used, I seem to recall. Arguments could be defined as keyword or as positional or as "positional unless given as a keyword". I no longer recall if explicit data types could be given for how the argument was to be stored, but it was possible to restrict the form of input arguments (e.g., to specify that an argument _had_ to be an integer with exponential format disallowed.) Valid values for arguments could be given as a list of specific words. Abbreviations were handled -- only as much of the word as was necessary to disambiguate it was required to be entered by the user.

I miss some features of VMS...

[Ben Petschel]

A nice feature of the R language is non-constant default inputs, for example function(x,n=length(x)), whereas Python defines the defaults at compile time. Having this feature as well as named arguments in the function call such as foo(n=1) would save the tedium of processing varargin.

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

[Royi Avital]

I think Octave implemented this.

[Steven Lord]

Release R2019b allows you to declare specific restrictions (and default values) for input arguments. See more in the Release Notes and the documentation page to which that note links.

[Walter Roberson]

That's some change!

[Adam]

I hadn't even noticed R2019b is out. The e-mail notifications of a new release seem to be a little tardy I've noticed! Not that I really need the new release as soon as it is out though.

[Rik]

They're not fully done implementing it anyway; the MinGW compiler installer isn't working yet. I hope they will post something there when it is, because I will probably forget to install it untill I'm getting weird errors...

Answer 15

[Daniel Shub]

A function to check if a string clashes with an official MATLAB function. Something like Jan's UniqueFuncNames, but with support for all MATLAB toolboxes. Preferably something that can handle different MATLAB versions and input classes. In other words randi exists in 2012a, but was it a function in r2008a or is there an fft function for class int16. The "which" function is helpful for your current version, but only for toolboxes you own.

[Jan]

It would be easy to expand UniqueFuncNames, if somebody with access to full Matlab installations assists.

[Daniel Shub]

While it would be easy, this is something that I think TMW should supply and maintain. I would think they could even automate the process.

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

[Walter Roberson]

I have started playing with Virtual Machines on my Mac. I might still have an XP install disk around, so I could potentially install quite a few versions back. However, I have not found any way of figuring out the names of the internal routines that do not happen to have a corresponding .m file for documentation purposes.

Jan, do you have an automated discovery routine that can be pointed at a base installation? Easiest would be if it did not require running the release so I didn't have to install the old OS's.

I do not have access to all toolboxes, but we could at least get somewhere.

[Steven Lord]

In release R2014b we added capability where MATLAB suggests which MathWorks product is required for an undefined function, which is a step towards what was requested. See the item "Suggested MathWorks products for undefined functions" in the Language and Programming section of the Release Notes for MATLAB for release R2014b for more information.

Answer 16

[Will]

Syntax highlighting that picks up fields of structures, not just the structure names themselves.

I want to know where I use a given field, and to be able to universally alter all uses if I rename it, as you can with variable names, structure names, etc.

[Rik]

Before I learned about the %#ok I used this as a feature to hide some warnings. In hindsight a terrible idea.

[dpb]

"Before I learned about the %#ok..."

OK, that's greek to me...???

[Steven Lord]

Code Analyzer warning suppression. See the "Adjust Code Analyzer Message Indicators and Messages" section on this documentation page for more information.

[Lucademicus]

I guess Rik's comment is offtopic, I agree with Will.

Automatically highlighting a selected field of a struct (or property of an object) would be very helpfull. I'm using VS Code, which is a bit better because it highlights other words similar to the selected field.

Answer 17

[Walter Roberson]

A notation to be able to represent multi-dimensional data, instead of having to cat(N,...) the dimensions together.

This notation should in turn be understood by (e.g.) load routines

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

Answer 18

[Walter Roberson]

More flexibility to work with I/O streams rather than having to have everything in memory.

As a simple example: unzip a single file starting from the current position in an I/O stream, rather than having to unzip to disk and read the resulting file.

[Walter Roberson]

I think it would be acceptable for this purpose to introduce a new IOStream object, with IOStream(fid) pulling out the object for the file id #fid . To start the basic properties of the IOStream would be the fields you get from applying fopen() to that fid.

A Position property when read could substitute for ftell(fid), and when set could substitute for fseek(fid,POS,'bof') .

Mainly, though, by having a distinct object class wrapping the fid, it would become easier to overload methods, especially in places where a file name string is expected as the first parameter.

imwrite(Array,IOStream(4)) would write to the given stream rather than to a file name.

This becomes more powerful when you allow IOStreams to become associated with blocks of memory, as per traditional unix memmap semantics -- which allow dual access through the fid and through memory

Or perhaps it would be better to have an IOObject class with subclasses for "stream" (non-seekable) and "block" (seekable) objects. That leads into possibilities such as asynch reads with callbacks, and scatter-gather I/O... maybe even DMA to devices...

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

[Andrew Janke]

I would like to see this. And conversely, there are some functions that only work on files (where you supply the file name); it would be nice to be able to supply an equivalent of Java's ByteArrayInputStream to get them to work on an in-memory buffer instead.

[Steven Lord]

This doesn't sound exactly like what you requested, but could a datastore array (introduced in release R2014b) satisfy some of your requirements for such an I/O stream, possibly if used to create a tall array?

Answer 19

[Walter Roberson]

Short-circuiting vectorized conditional tests. This might require introducing a new keyword.

For example,

x > y/2

would normally compute the entire element-by-element vector x(K) > Y(K)/2, and then that vector would be processed within whatever expression was around it. For example,

find(x > y/2,1,'first')

or

if any(x > y/2)

But logically these don't need the entire vector result, just a single scalar result.

A lot of the time people are working with vectors too short for BLAS to kick in, but long enough that the time savings of short-circuiting would add up.

Imagine, for example, a new keyword "first":

find(first x > y/2)

or

if first x > y/2

"first" could return either 0 or [] if not found; [] would be more consistent, and ~[] is false so ~first would work like ~any(). On the other hand, what it should return so that it works with find() and logic conditions is a good question.

[Jan]

See these FEX submissions:

http://www.mathworks.com/matlabcentral/fileexchange/27857-anyExceed

http://www.mathworks.com/matlabcentral/fileexchange/26867-anyEq

[Royi Avital]

What's the difference between FEX and MEX?

[Walter Roberson]

FEX is the MATLAB File Exchange. MEX is the MATLAB API and compiling tool for C, C++, and Fortran to interface with MATLAB.

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

Answer 20

[Walter Roberson]

Pipes / popen() / ability to communicate interactively with other programs without having to use tcp/udp .

[Walter Roberson]

(This has not been implemented yet, as of R2016a)

Answer 21

[Walter Roberson]

Inspired by Carl's csvread requests:

A textscan format specifier indicating that a date was expected at that position, possibly including embedded blanks. A modifier would allow specification of one of the standard date format numbers. Output would be a serial date number.

Extra points for a format specifier that allowed the standard date elements, such as

%t{mmm yy, HH:MM}

[Walter Roberson]

(This was implemented about R2014b.)

[Walter Roberson]

(However, handling spaces in a %D format requires that the WhiteSpace property be set to exclude spaces.)

[Walter Roberson]

readtable() and kin are getting increasingly better at deducing date format, including when there are are spaces.

Answer 22

[David Goldsmith]

Multiple inspector instances in one instance of MATLAB: I want to be able to "inspect" more than one object at a time (e.g., to be able to compare property values); presently, I have to launch a new instance of MATLAB for each distinct inspector instance I want to use simultaneously--a tremendous waste of resources! (Don't worry, I'm submitting a formal enhancement request.)

[Walter Roberson]

I hit this yesterday. One of my first time using the inspector, dropped into the extended color-picker subsection, chose colors, and to physically write down the rgb values and close back up through several levels before I could edit the new rgb values into the code I was touching up :(

[Aurelien Queffurust]

Definetly agree: inspecting mustiple uicontrols within GUIDE at the same time should be implemented!

[Image Analyst]

Are you saying that MATLAB has a built-in color-picker tool dialog box? What is the function called? I have a need for a user to select a color via the regular color picker kind of tool that you see in so many other applications. It will be used to specify colors for the things (text, circles, etc.) that I put into the graphical overlay above the image I've displayed. Or do I need to pick one of these from the File Exchange?

[Jan]

@Image Analyst: Do you mean uisetcolor? Or perhaps Undocumented: color selection components

[Image Analyst]

Yes, that's it! I think it's a major omission that this function doesn't come up when you search for "color" in the help, and it's not even listed as a "see also" in the ColorSpec page of the help. I'll send in a feature request for that. Thanks for telling us about this function.

[Jan]

@IA: It is easy to find:

docsearch color

Then it is about the 600th(!) element in the list on the left, when you sort the results alphabetically, what has been possible in the help browser of R2009a. In R2011b I do not find uisetcolor through docsearch at all. And after too many negative opinions I'm not eager to search in the help browser of R2013a.

So you are right: This will be an important enhancement request. I post a question here also, because it will be published earlier than the modified help text most likely ;-)

[Walter Roberson]

R2013, if I type uisetcolor into the GUI search engine, it shows up without difficulty. But if you tried to search for it without knowing the right verb (e.g., if you were looking for "pick color") then good luck.

Answer 23

[Walter Roberson]

If there is an atan2() function, why isn't there an acot2() function or acos2() or asin2() ?? Equal time for arc functions!

[Andrew Newell]

We shall overco-o-ome! We shall overco-o-ome! We shall overcome some day-a-a-a-ay!

Answer 24

[Dan K]

A true polar plot. I've been using an old copy of mmpolar (thanks Duane) for years. It seems ridiculous that the built in functionality has hard coded axis labels,etc. It's even brutal trying to adjust things that can be accessed, since the underlying coordinates are all Cartesian.

[Walter Roberson]

Also, we get a surprising number of requests for log-polar plots. Yes, that causes problems for rho that are negative, and requires an infinite amount of canvas to represent from rho = 0 to any positive rho, but people want it anyhow.

[Steven Lord]

Release R2016a introduced the polarplot and polaraxes functions.

Answer 25

[Ken]

What is missing in MATLAB?

Here is my quick thought for today (and most days when editing large sequences of code) :

In the native editor, it is nice when clicking on the if, try, for, etc... beinning construct or the end statement and it reference the line that may be far off the screen for it paired construct beginning/end but why hasn't anyone implemented the begging construct highlight to also include any of the else/catch in between constructs?

It would be nice when reviewing someone else's code to simply click on the beginning logic construct and see all sub blocks (if any) along with the location of the end construct statement.

[craq]

I wondered that myself, especially since clicking on the else will show you the corresponding if. I'd add switch/case to your list.

Answer 26