Syntax to save Neural Network Object in Matlab R2011a - matlab

I have trained a neural network using MATLAB and I need to save it to be able to test it in the future.
I would like the appropriate syntax on how I can do this. Please note that I am aware of the graphical toolbox which easily lets you save a trained network, but unfortunately the options provided are not sufficient for me and so I have to create and train a network of my own using code.
I have tried the following syntax to save a trained network. (Most of the syntax is copy paste from the internet with little experimentation of my own.)
save('net.mat', net)
save(net)
save('net.net', net, '-mat')
save('net.net', net)
But I always seem to get the same error:
??? Error using ==> save
Argument must contain a string.
If there are experienced users who could lead me to a concrete answer which is sure to work, I would be very grateful.

From here.
When using parentheses (function syntax) you need to use quotes around the object name. Note that the function requires an object description and not the object itself. This makes sense since it can also take wildcards that describe multiple objects and then save them all into the '.mat' file.
In short, when you're using parentheses, use this:
save('net.mat', 'net')
Alternatively you can use the command syntax (no parentheses) and then quotes are optional. All options below are valid (and equivalent):
save net.mat net
save net.mat 'net'
save 'net.mat' net
save 'net.mat' 'net'
See also Command vs. Function Syntax

Related

Overwrote built in function - Standard deviation

I want to have a std.m file for the standard deviation. It is in data fun toolbox, but, by mistake, I changed the code and the std command is not working anymore. How can I run the original std (standard deviation) command?
Taking all the comments out, the function std.m is actually extremely simple:
function y = std(varargin)
y = sqrt(var(varargin{:}));
This is the definition of the standard deviation: the square root of the Variance.
Set built-in functions to Read-Only
Now don't go breaking the var.m file because it is more complex and I wonder if there would be copyright issue to display the listing here.
To avoid the problem of breaking built-in files, it is advisable to set all your Matlab toolbox files as Read Only. I remember old Matlab installer giving the option to do that at install time. I don't know if the installer still offers the option, but if not it is extremely easy to do it manually (on Windows, just select your folders, right-click Properties, tick read only and accept to propagate the property to all subfolders and files).
Overloading
Once this is done, your built-in files are safe. You can still modify the default behavior of a built-in function by overloading it. This consist in writing a function with the same name and arrange for it to be called before the default function (your overload function becomes the default one).
This article explain how to overload user functions.
Matlab does not recommend to directly overload the built-in functions (rather call it another name like mySTD.m for example), but if you insist it is perfectly feasible and still a much better option than modifying the built-in function... at least the original function is still intact somewhere.

At which lines in my MATLAB code a variable is accessed?

I am defining a variable in the beginning of my source code in MATLAB. Now I would like to know at which lines this variable effects something. In other words, I would like to see all lines in which that variable is read out. This wish does not only include all accesses in the current function, but also possible accesses in sub-functions that use this variable as an input argument. In this way, I can see in a quick way where my change of this variable takes any influence.
Is there any possibility to do so in MATLAB? A graphical marking of the corresponding lines would be nice but a command line output might be even more practical.
You may always use "Find Files" to search for a certain keyword or expression. In my R2012a/Windows version is in Edit > Find Files..., with the keyboard shortcut [CTRL] + [SHIFT] + [F].
The result will be a list of lines where the searched string is found, in all the files found in the specified folder. Please check out the options in the search dialog for more details and flexibility.
Later edit: thanks to #zinjaai, I noticed that #tc88 required that this tool should track the effect of the name of the variable inside the functions/subfunctions. I think this is:
very difficult to achieve. The problem of running trough all the possible values and branching on every possible conditional expression is... well is hard. I think is halting-problem-hard.
in 90% of the case the assumption that the output of a function is influenced by the input is true. But the input and the output are part of the same statement (assigning the result of a function) so looking for where the variable is used as argument should suffice to identify what output variables are affected..
There are perverse cases where functions will alter arguments that are handle-type (because the argument is not copied, but referenced). This side-effect will break the assumption 2, and is one of the main reasons why 1. Outlining the cases when these side effects take place is again, hard, and is better to assume that all of them are modified.
Some other cases are inherently undecidable, because they don't depend on the computer states, but on the state of the "outside world". Example: suppose one calls uigetfile. The function returns a char type when the user selects a file, and a double type for the case when the user chooses not to select a file. Obviously the two cases will be treated differently. How could you know which variables are created/modified before the user deciding?
In conclusion: I think that human intuition, plus the MATLAB Debugger (for run time), and the Find Files (for quick search where a variable is used) and depfun (for quick identification of function dependence) is way cheaper. But I would like to be wrong. :-)

Use of %# notation for declaring dependencies

In MATLAB, you can declare a function dependency with:
%#function myExtraFunctionName
Doing so tells MATLAB that myExtraFunctionName is required by the script or function to operate, even if it's called by an eval statement or some other method that the various dependency checkers or compilers can't figure out.
I have several files that load in .mat or other data files that are required for the script to run, and I would like to include them in a similar manner so that when I run a dependency check with, say fList = matlab.codetools.requiredFilesAndProducts, it will find these data files as well. Ultimately what I would like to be able to do is generate the list of files and pass it to zip to archive every file required to run a given script or function, including data files.
Trying to find any documentation on this feature is challenging because the MATLAB help won't let you just type in %# and searching for %#function just searches for function. Google does the same thing: "hash percent function" returns lots of information on hash tables, "%#function matlab" strips out the important characters, and "declare matlab function" "declare matlab function dependency" turns up nothing useful. I don't remember where I encountered this syntax, so I don't even know if this is a documented feature or not.
I have two questions:
Can someone point me to documentation on this syntax along with some clues as to what keywords I should be using to search?
Can this be used to declare dependencies other than m-files and, if not, how can I go about doing that?
%#function is a pragma directive that informs MATLAB Compiler that the specified function will be called indirectly using feval, eval, or the like.
This is important because the static code analyzer will not be able to detect such dependencies on its own. For instance the name of the function could be stored in a string as in:
fcn = 'myFunction';
feval(fcn)
As far as I know, this is only used by the MATLAB Compiler, nothing else.
There are other similar pragmas. For example MATLAB Coder has %#codegen compiler directive.
I don't have any answer, but maybe you can use this website:
http://www.symbolhound.com/
It let you do search using symbols.

Anonymous function corruption in MATLAB. What does '#sf%' mean?

I was stumped by a segmentation fault in MATLAB.
It seems like it was caused by an anonymous function that was loaded from a mat file.
The original anonymous function handle was:
#(x)scaledNlfun(x,#logexp1,1e3)
But when it is loaded, it becomes:
#sf%1#(x)scaledNlfun(x,#logexp1,1e3)
It seems to be okay, when I call it in command line, but it creates a segmentation fault (or Segmentation violation) within a function. Not the function call itself, but a few lines after that. In debugging mode, if I step through the statement, it is fine as well.
The stack trace shows bunch of
[ 0] 0x00002b20b97baba4 /usr/local/MATLAB/R2013a/bin/glnxa64/libmwm_interpreter.so+04127652
and it happens on both MATLAB 2012a and 2013a on a Linux 2.6.18-371.3.1.el5 SMP.
This function handle was saved within a parfor loop using '-v7.3' option because the struct that contains the handle was too big. If I replace the anonymous function after loading the mat file, everything works fine, so I'm thinking the matlab load function has a bug.
Unfortunately, I cannot create a minimal example to reproduce the error. I tried saving anonymous function handles within parfor with '-v7.3', but without the other complex data structures, it seems to work fine. But I have 80 mat files that would reliably crash matlab (many of them more than 1GB).
In any case, does anybody know what that "#sf%" mean? (it's not the stateflow toolbox)
The core of the problem seems to be that you have #sf%1# where you would expect # just looking at this, I can think of a few possibilities:
Somehow sf%1# was inserted after the original #
Somehow #sf%1# was substituted in place of the original #
Somehow #sf%1 was attached before the original #
I would actually bet on the third one, but here are the most logical scenarios I can think of that could cause this problem:
Perhaps there was an invisible char?
Perhaps some kind of strange character conversion?
Probably a situation where two things are stored in a variable instead of one. Perhaps something like #s or #sf and some separating characters.
All in all, this does not explain why it would go well if you run the entire program in the console, but perhaps you just ran part of it. In that case these could be some things to look out for.

Is there a way to do command aliasing in matlab R2011b?

I am relatively new at Matlab.
I am trying to create an alias for a command that looks like the following.
run('full/path/to/some/script').
In particular, I would like to be able to write something equivalent to Bash's
alias myAlias = run('full/path/to/some/script')
And then be able to type myAlias and get the same effect as the right hand side.
I have looked at the documentation here, but I still get the error Undefined function or variable 'alias' when I try to use it, even after I first type syms at the prompt, so I believe that either I am not importing the toolbox correctly or this is not a feature in R2011b.
One additional requirement is that I would like the alias to stick even after I call clear, which should clear all the other active variables in the workspace.
for example:
f = #() run('foldername\scriptname')
then just writing f() will execute scriptname.
Here I've used an anonymous function, you can add more content to it if needed.
You can make #natan's answer tolerate clearing the workspace by making it an m-file.
In myAlias.m, put run('full/path/to/some/script'). I'm sure you are aware of this solution, but you might not want to do so, because of the resulting messy file system.
You can simply add the m-file to some folder and use addpath('where/ever/you/put/the/script') to make it accessible.