So I am creating an app to work out a value based on a series of variables. The variables are:
Gender
Age
Weight
Creatinine
Here's what the app looks like:
In order to simplify the process somewhat I decided to make the gender selection a dropdown menu, this has caused me some issues since I have it setup like so:
And the maths associated with the button looks like so:
function CalculateButtonPushed(app, event)
gender = app.PatientGenderDropDown.Value ;
age = app.PatientAgeEditField.Value ;
weight = app.LeanBodyWeightEditField.Value ;
serum = app.SerumCreatinineEditField.Value ;
final = (gender*(age)*weight) / (serum) ;
app.ResultEditField.Value = final ;
end
end
Running this gives the following error:
Error using
matlab.ui.control.internal.model.AbstractNumericComponent/set.Value
(line 104) 'Value' must be numeric, such as 10.
As far as I am aware, the values I input into ItemsData are numeric values. Have I missed something or is there a better way to do this?
If you put a breakpoint in the offending file on the appropriate line (by running the below code),
dbstop in uicomponents\+matlab\+ui\+control\+internal\+model\AbstractNumericComponent.m at 87
you could see the following in your workspace, after clicking the button:
There are two separate problems here, both of which can be identified by looking at the newValue validation code (appearing in AbstractNumericComponent.m):
% newValue should be a numeric value.
% NaN, Inf, empty are not accepted
validateattributes(...
newValue, ...
{'numeric'}, ...
{'scalar', 'real', 'nonempty'} ...
);
Here are the issues:
The new value is a vector of NaN.
The reason for this is in this line:
final = (gender*(age)*weight) / (serum) ;
where serum has a value of 0 - so this is the first thing you should take care of.
The new value is a vector of NaN.
This is a separate problem, since the set.Value function (which is implicitly called when you assign something into the Value field), is expecting a scalar. This happens because gender is a 1x4 char array - so it's treated as 4 separate numbers (i.e. the assumption about ItemsData being a numeric is incorrect). The simplest solution in this case would be to str2double it before use. Alternatively, store the data in another location
(such as a private attribute of the figure), making sure it's numeric.
Related
I have an excel file and I need to read it based on string values in the 4th column. I have written the following but it does not work properly:
[num,txt,raw] = xlsread('Coordinates','Centerville');
zn={};
ctr=0;
for i = 3:size(raw,1)
tf = strcmp(char(raw{i,4}),char(raw{i-1,4}));
if tf == 0
ctr = ctr+1;
end
zn{ctr}=raw{i,4};
end
data=zeros(1,10); % 10 corresponds to the number of columns I want to read (herein, columns 'J' to 'S')
ctr=0;
for j = 1:length(zn)
for i=3:size(raw,1)
tf=strcmp(char(raw{i,4}),char(zn{j}));
if tf==1
ctr=ctr+1;
data(ctr,:,j)=num(i-2,10:19);
end
end
end
It gives me a "15129x10x22 double" thing and when I try to open it I get the message "Cannot display summaries of variables with more than 524288 elements". It might be obvious but what I am trying to get as the output is 'N = length(zn)' number of matrices which represent the data for different strings in the 4th column (so I probably need a struct; I just don't know how to make it work). Any ideas on how I could fix this? Thanks!
Did not test it, but this should help you get going:
EDIT: corrected wrong indexing into raw vector. Also, depending on the format you might want to restrict also the rows of the raw matrix. From your question, I assume something like selector = raw(3:end,4); and data = raw(3:end,10:19); should be correct.
[~,~,raw] = xlsread('Coordinates','Centerville');
selector = raw(:,4);
data = raw(:,10:19);
[selector,~,grpidx] = unique(selector);
nGrp = numel(selector);
out = cell(nGrp,1);
for i=1:nGrp
idx = grpidx==i;
out{i} = cell2mat(data(idx,:));
end
out is the output variable. The key here is the variable grpidx that is an output of the unique function and allows you to trace back the unique values to their position in the original vector. Note that unique as I used it may change the order of the string values. If that is an issue for you, use the setOrderparameter of the unique function and set it to 'stable'
I am trying to define the following function in MATLAB:
file = #(var1,var2,var3,var4) ['var1=' num2str(var1) 'var2=' num2str(var2) 'var3=' num2str(var3) 'var4=' num2str(var4)'];
However, I want the function to expand as I add more parameters; if I wanted to add the variable vark, I want the function to be:
file = #(var1,var2,var3,var4,vark) ['var1=' num2str(var1) 'var2=' num2str(var2) 'var3=' num2str(var3) 'var4=' num2str(var4) 'vark=' num2str(vark)'];
Is there a systematic way to do this?
Use fprintf with varargin for this:
f = #(varargin) fprintf('var%i= %i\n', [(1:numel(varargin));[varargin{:}]])
f(5,6,7,88)
var1= 5
var2= 6
var3= 7
var4= 88
The format I've used is: 'var%i= %i\n'. This means it will first write var then %i says it should input an integer. Thereafter it should write = followed by a new number: %i and a newline \n.
It will choose the integer in odd positions for var%i and integers in the even positions for the actual number. Since the linear index in MATLAB goes column for column we place the vector [1 2 3 4 5 ...] on top, and the content of the variable in the second row.
By the way: If you actually want it on the format you specified in the question, skip the \n:
f = #(varargin) fprintf('var%i= %i', [(1:numel(varargin));[varargin{:}]])
f(6,12,3,15,5553)
var1= 6var2= 12var3= 3var4= 15var5= 5553
Also, you can change the second %i to floats (%f), doubles (%d) etc.
If you want to use actual variable names var1, var2, var3, ... in your input then I can only say one thing: Don't! It's a horrible idea. Use cells, structs, or anything else than numbered variable names.
Just to be crytsal clear: Don't use the output from this in MATLAB in combination with eval! eval is evil. The Mathworks actually warns you about this in the official documentation!
How about calling the function as many times as the number of parameters? I wrote this considering the specific form of the character string returned by your function where k is assumed to be the index of the 'kth' variable to be entered. Array var can be the list of your numeric parameters.
file=#(var,i)[strcat('var',num2str(i),'=') num2str(var) ];
var=[2,3,4,5];
str='';
for i=1:length(var);
str=strcat(str,file(var(i),i));
end
If you want a function to accept a flexible number of input arguments, you need varargin.
In case you want the final string to be composed of the names of your variables as in your workspace, I found no way, since you need varargin and then it looks impossible. But if you are fine with having var1, var2 in your string, you can define this function and then use it:
function str = strgen(varargin)
str = '';
for ii = 1:numel(varargin);
str = sprintf('%s var%d = %s', str, ii, num2str(varargin{ii}));
end
str = str(2:end); % to remove the initial blank space
It is also compatible with strings. Testing it:
% A = pi;
% B = 'Hello!';
strgen(A, B)
ans =
var1 = 3.1416 var2 = Hello!
I'm creating a program to simulate a random walk and it requires the user to input an integer number of steps to take for the walk.
The prompt for this uses code very similar to this:
**% Ask user for a number.
defaultValue = 45;
titleBar = 'Enter a value';
userPrompt = 'Enter the integer';
caUserInput = inputdlg(userPrompt, titleBar, 1,{num2str(defaultValue)});
if isempty(caUserInput),return,end; % Bail out if they clicked Cancel.
% Round to nearest integer in case they entered a floating point number.
integerValue = round(str2double(cell2mat(caUserInput)));
% Check for a valid integer.
if isnan(integerValue)
% They didn't enter a number.
% They clicked Cancel, or entered a character, symbols, or something else not allowed.
integerValue = defaultValue;
message = sprintf('I said it had to be an integer.\nI will use %d and continue.', integerValue);
uiwait(warndlg(message));
end**
However, I want it to simply display the "Enter a value" prompt again if the user does not enter an integer the first time i.e. 4.4.
Any ideas?
Thanks!
if (mod(integerValue,1) == 0)
will evaluate to true if integerValue is an integer. Simply augment your if statement w/ this logic. You might want to consider changing to using a while loop so the user can enter bad input more than once.
The first answer is totally correct for checking for an integer value, but to address the "show prompt again" issue you can just use a loop conditioning it to get the exact kind of data you want:
caUserInput = nan; %or anything worng for that matter
while isempty(caUserInput) || isnan(caUserInput)
caUserInput = inputdlg(userPrompt, titleBar, 1,{num2str(defaultValue)});
end
if you want you can start it again with different argument lines in a more fancy style:
inputiswrong = 1; %or anything worng for that matter
while inputiswrong
inputiswrong = 0;
caUserInput = inputdlg(userPrompt, titleBar, 1,{num2str(defaultValue)});
if isempty(caUserInput )
userPrompt = 'Try again with an input';
inputiswrong = 1;
end
if isnan(caUserInput )
userPrompt = 'not really a number';
inputiswrong = 1;
end
%and so on
end
In both scenarios you should consider transforming the caUserInput to something you could use, i think inputdlg returns a cell so maybe a cell2mat() around the inputdlg().
Remember that unspecified inputs in MATLAB are double-precision by default. For instance a=3 is not an integer. So you should consider two cases:
Integer type
If you are talking about integer type in MATLAB the easiest way is to use isinteger function by MATLAB:
tf = isinteger(A)
for instance:
isinteger(4.4)
=
0
as I mentioned before, 3 is not an integer:
isinteger(3)
=
0
but this one is integer actually:
isinteger(uint8(3))
=
1
To repeat the input query also easily use the same function in a while loop
while ~isinteger(a)
disp('enter an integer');
....
end
Constant double-precision with no decimal
But if you are considering normal constant inputs to be integers you could convert them to integer and compare the result with the original value:
while a ~= double(int64(a))
disp('enter an integer');
....
end
int64 converts the double type to integer, and double converts it back to double. If in this process the number remains unchanged, then you could consider that it was intended to be an integer.
Recommendation for you specific program
I would use a fix function to get rid of the decimal parts. Usually when you receive a double-precision number including decimal values, the main intention is the the number before the floating point. So in many algorithms it is common practice to use fix to round each element of the given number to the nearest integer toward zero.
I'm trying to conjure up a little parser that reads a .txt file containing parameters for an algorithm so i don't have to recompile it everytime i change a parameter. The application is C code generated from .m via coder, which unfortunately prohibits me from using a lot of handy matlab gimmicks.
Here's my code so far:
% read textfile
string = readfile(filepath);
% do fancy rearranging
linebreaks = zeros(size(string));
equals = zeros(size(string));
% find delimiters
for n=1:size(string,2)
if strcmp(string(n),char(10))
linebreaks(n) = 1;
elseif strcmp(string(n), '=')
equals(n) = 1;
end
end
% write first key-value pair
idx_s = find(linebreaks);idx_s = [idx_s length(string)];
idx_e = find(equals);
key = string(1:idx_e(1)-1);
value = str2double(string(idx_e(1)+1:idx_s(1)-1));
parameters.(key) = value;
% find number of parameters
count = length(idx_s);
% write remaining key-value pairs
for n=2:count
key = string(idx_s(n-1)+1:idx_e(n)-1);
value = str2double(string(idx_e(n)+1:idx_s(n)-1));
parameters.(key) = value;
end
The problem is that seemingly coder does not support dynamic fieldnames for structures like parameters.(key) = value.
I'm a bit at a loss as to how else i am supposed to come up with a parameter struct that holds all my key-value pairs without hardcoding it. It would somewhat (though not completely) defeat the purpose if the names of keys were not dynamically linked to the parameter file (more manual work if parameters get added/deleted, etc.). If anybody has an idea how to work around this, i'd be very grateful.
As you say, dynamic fieldnames for structures aren't allowed in MATLAB code to be used by Coder. I've faced situations much like yours before, and here's how I handled it.
First, we can list some nice tools that are allowed in Coder. We're allowed to have classes (value or handle), which can be quite handy. Also, we're allowed to have variable sized data if we use coder.varsize to specifically designate it. We also can use string values in switch statements if we like. However, we cannot use coder.varsize for properties in a class, but you can have varsized persistent variables if you like.
What I'd do in your case is create a handle class for storing and retrieving the values. The following example is pretty basic, but will work and could be expanded. If a persistent variable were used in a method, you could even create a varsized allocated storage for the data, but in my example, it's a property and has been limited in the number of values it can store.
classdef keyval < handle %# codegen
%KEYVAL A key and value class designed for Coder
% Stores an arbitrary number of keys and values.
properties (SetAccess = private)
numvals = 0
end
properties (Access = private)
intdata
end
properties (Constant)
maxvals = 100;
maxkeylength = 30;
end
methods
function obj = keyval
%KEYVAL Constructor for keyval class
obj.intdata = repmat(struct('key', char(zeros(1, obj.maxkeylength)), 'val', 0), 1, obj.maxvals);
end
function result = put(obj, key, value)
%PUT Adds a key and value pair into storage
% Result is 0 if successful, 1 on error
result = 0;
if obj.numvals >= obj.maxvals
result = 1;
return;
end
obj.numvals = obj.numvals + 1;
tempstr = char(zeros(1,obj.maxkeylength));
tempstr(1,1:min(end,numel(key))) = key(1:min(end, obj.maxkeylength));
obj.intdata(obj.numvals).key = tempstr;
obj.intdata(obj.numvals).value = value;
end
function keystring = getkeyatindex(obj, index)
%GETKEYATINDEX Get a key name at an index
keystring = deblank(obj.intdata(index).key);
end
function value = getvalueforkey(obj, keyname)
%GETVALUEFORKEY Gets a value associated with a key.
% Returns NaN if not found
value = NaN;
for i=1:obj.numvals
if strcmpi(keyname, deblank(obj.intdata(i).key))
value = obj.intdata(i).value;
end
end
end
end
end
This class implements a simple key/value addition as well as lookup. There are a few things to note about it. First, it's very careful in the assignments to make sure we don't overrun the overall storage. Second, it uses deblank to clear out the trailing zeros that are necessary in the string storage. In this situation, it's not permitted for the strings in the structure to be of different length, so when we put a key string in there, it needs to be exactly the same length with trailing nulls. Deblank cleans this up for the calling function.
The constant properties allocate the total amount of space we're allowed in the storage array. These can be increased, obviously, but not at runtime.
At the MATLAB command prompt, using this class looks like:
>> obj = keyval
obj =
keyval with properties:
numvals: 0
>> obj.put('SomeKeyName', 1.23456)
ans =
0
>> obj
obj =
keyval with properties:
numvals: 1
>> obj.put('AnotherKeyName', 34567)
ans =
0
>> obj
obj =
keyval with properties:
numvals: 2
>> obj.getvalueforkey('SomeKeyName')
ans =
1.2346
>> obj.getkeyatindex(2)
ans =
AnotherKeyName
>> obj.getvalueforkey(obj.getkeyatindex(2))
ans =
34567
If a totally variable storage area is desired, the use of persistent variables with coder.varsize would work, but that will limit the use of this class to a single instance. Persistent variables are nice, but you only get one of them ever. As written, you can use this class in many different places in your program for different storage. If you use a persistent variable, you may only use it once.
If you know some of the key names and are later using them to determine functionality, remember that you can switch on strings in MATLAB, and this works in Coder.
I am currently trying to map some data within a month depending on 'Month', 'week', 'day'.
This means that in principle I have three keys. I thought of following solutions to the problem:
1)
containers.Map(month,containers.Map(week,containers.Map(day,value)))
The problem with this solutions is to reference it I must use: How can I index a MATLAB array returned by a function without first assigning it to a local variable?.
And I find this solution rather "ugly".
2)
So another way would be to use a Map with multiple keys. The containers documentation show that only a single dimension key is allowed.
Question:
Do you have any trick to solve this multiple key problem?
Update/Solution:
I ended using a concatenated string as a key (as suggested) I added following piece of code to make the containers.Map as a proper multi-dimensional hashmap. Take a look below (I excluded week for simplification):
classdef example
properties
myMap % Map for storage
end
methods
function obj = example()
obj.myMap = containers.Map;
end
function obj2 = setVal(obj2,value,Month,DayType)
key = strcat(num2str(Month),'-',num2str(DayType));
obj2.myMap(key) = value;
end
function value = getValue(obj,Month,DayType)
key = strcat(num2str(Month),'-',num2str(DayType));
value = obj.myMap(key);
end
end
You could perhaps use all three of those keys to build a single key. I'm assuming this can be done as Month, week and day could be considered as unique. There is only one unique combination of these per occurrence. As such, simply take these keys and build them into single strings, then use theses as keys into your dictionary / containers.Map().
Here's an example:
%// Test data
month1 = 'May';
week1 = 2;
day1 = 'Thursday';
month2 = 'June';
week2 = 3;
day2 = 'Friday';
month3 = 'July';
week3 = 4;
day3 = 'Sunday';
%// Define keys
key1 = [month1 num2str(week1) day1];
key2 = [month2 num2str(week2) day2];
key3 = [month3 num2str(week3) day3];
%// Build dictionary
M = containers.Map();
M(key1) = 'Hello!';
M(key2) = 'Testing!';
M(key3) = 'Yes!';
%// Now test accessing
disp(M(key1));
disp(M(key2));
disp(M(key3));
The above code will take three months, three weeks and days, convert them into strings, and use these as keys into your dictionary. I don't know what the output type is for your purposes, so I just assigned strings. Note that I took the numbers and used num2str to convert the numbers into strings to ensure compatibility with the rest of the string. I don't know what data type week is (or any of the other variables in fact...), so simply use what I have and modify it for your own purposes.
I create the dictionary, then to test it, I access each of the values with each of the keys. As expected, my output is:
Hello!
Testing!
Yes!
There is a new MapNested class on Matlabs File-exchange:
http://de.mathworks.com/matlabcentral/fileexchange/62492-mapnested-implementation-for-nested-maps--map-of-maps-
or on github:
https://github.com/RolandRitt/Matlab-NestedMap
Check it out!
The syntax for setting an value is the following:
NMapobj = MapNested(); %constructor;
NMapobj(key1, key2, key3) = value;
for retrieving:
value = NMapobj(key1, key2, key3);