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how to generate a random number ?

Priom Rahman — Sat, 31 Jul 2010 02:05:04 -0400

Hi guys, just wondering if someone could help me work out the code to generate a random number between 0 and 1 ? with any number having an equal likelyhood of being generated ?

Re: Line segment intersection?

Steve — Sat, 31 Jul 2010 01:23:04 -0400

ImageAnalyst <imageanalyst@mailinator.com> wrote in message <8887b212-9387-4b54-af5f-6f8e388aa410@j8g2000yqd.googlegroups.com>...
> Are you (1) going to place all the blue lines first and then check
> (like your example), or are you (2) going to place one line at each
> iteration of a loop and then check against that one line (kind of like
> your explanation that mentioned a loop) and then break out of the loop
> if the latest line is within the radius?
>
> A dumb brute force way is to write the lines into a 2D matrix (image)
> and then use the Euclidean Distance Transform (bwdist() which is in
> the Image Processing Toolbox), but I bet there's a more clever
> analytical method.

Thanks for your answer.
Every line is growing over time and i want to check which lines are colliding and stop the growth of these lines. Like in my example.

I'm using such a 2D matrix at the moment, but when the lines get very long this matrix gets very huge, sometimes more than the allowed variable size allowed.

So I'm looking for an analytical way. This is really tricky...

Re: Line segment intersection?

ImageAnalyst — Sat, 31 Jul 2010 01:13:02 -0400

Are you (1) going to place all the blue lines first and then check
(like your example), or are you (2) going to place one line at each
iteration of a loop and then check against that one line (kind of like
your explanation that mentioned a loop) and then break out of the loop
if the latest line is within the radius?

A dumb brute force way is to write the lines into a 2D matrix (image)
and then use the Euclidean Distance Transform (bwdist() which is in
the Image Processing Toolbox), but I bet there's a more clever
analytical method.

Anushka for Shape FX Hot Shot Thigh Gel

ANUSHKA — Sat, 31 Jul 2010 00:58:10 -0400

Anushka for Shape FX Hot Shot Thigh Gel

**************************************
http://sites.google.com/site/anushkaphotosalert

Re: Line segment intersection?

Steve — Sat, 31 Jul 2010 00:53:03 -0400

> Does it only matter if they intersect once? I.e. If the line is intersected by _any_ other line it's true or do you need the number that intersect it?
>
> If you just need a boolean value for each line this doesn't sound like such a difficult problem as any time there is an intersection, both lines don't need to have any further calculations done for them.
> To do this I would set up a sparse upper triangular matrix where each row/column corresponds to 1 line and traverse it horizontally. Once the condition of intersection is met; neither of those rows will need traversed any further cutting down on necessary computations. You could have a table with the points and circle radius/location so that a function; given the two indexes could check the criteria for intersection.
>
> Just a few thoughts; good luck!
> -Sean

Well, the problem is that I don't need the intersection point. As soon as a part of any another line is within the certain radius of the tip of my line, this is what I would need. A boolean value would be ok for the first time.
And I don't want to have such a matrix in the background. I have more than 30000 lines, which is more than the allowed variable size in matlab. A vektorized solution would be the best - if possible.

Re: [Q] Programatically set bookmarks in matlab editor?

Walter Roberson — Fri, 30 Jul 2010 23:44:21 -0400

Kevin wrote:
> Is this possible?

My memory is going. :( I thought that last night or this morning I had read a
posting from someone at Mathworks showing the class to access for another
desktop related function, and I was going to look at that posting and see if I
could figure out some places to look to answer your question. I went back
through 4 days of postings and could not find anything close to what I was
thinking of. Sorry.

Possibly, http://undocumentedmatlab.com might have some useful information
about this; it's the sort of trouble that Yair would get into :p

Re: TechTradeTool help

Walter Roberson — Fri, 30 Jul 2010 23:40:29 -0400

Cren Soppelsa wrote:
> Hi all, I downloaded the following file: TechTradeTool
>
> http://www.mathworks.com/matlabcentral/fileexchange/3806-techtradetool
>
> I tried to use it, but starting "Plot Trading System" button gives me
> the following error message:
>
> ??? Error using ==> tsmovavg
> Invalid number of inputs.
>
> Error in ==> movAv at 3
> tsOut = tsmovavg (tsIn, 's', (iDays-1), 0,1);

> What's the problem? How can I solve it?

It appears that the interface for tsmovavg() has changed over the years.

I am not certain, but comparing documentation of the old interface,

http://www.math.carleton.ca/old/help/matlab/MathWorks_R13Doc/toolbox/ftseries/tsmovavg.html

against the new

http://www.mathworks.com/access/helpdesk/help/toolbox/finance/tsmovavg.html

the documented difference is that the "lead" parameter has been dropped. In
the call there, "lead" would correspond to the (iDays-1) expression.

However, if you examine what the parameter does in the old interface and
compare to the new interface, the semantic meaning of what used to be called
"lead" _seems_ to be the same as what is now called "lag", and there does not
appear to be any equivalent to what was formally called "lag". The "lag" value
that is coded there is the 0, so what used to be called "lag" was effectively
not used before.

If I am correct in my interpretation of the wording of the new documentation,
the implication is that you should be able to fix the code by deleting the 0,
out of the tsmovavg call in the movAv routine.

It would not surprise me if you encounter other similar problems, but it's
worth a shot.

"An error occurred while reading the desktop configuration"

Peter — Fri, 30 Jul 2010 23:27:04 -0400

I think this is only the 2nd time I have started up matlab - I am a new user. I ran it for many days before having to restart the pc for other reasons. I first shut down matlab.

Now when I start it up it runs fine but keeps giving me this message in the command window - "Warning: An error occurred while reading the desktop configuration file. Using the default configuration."

Can anyone tell me what I should do to fix this?

Thanks

(Running on Windows 7 professional)

TechTradeTool help

Cren Soppelsa — Fri, 30 Jul 2010 23:25:27 -0400

Hi all, I downloaded the following file: TechTradeTool

http://www.mathworks.com/matlabcentral/fileexchange/3806-techtradetool

I tried to use it, but starting "Plot Trading System" button gives me the following error message:

??? Error using ==> tsmovavg
Invalid number of inputs.

Error in ==> movAv at 3
tsOut = tsmovavg (tsIn, 's', (iDays-1), 0,1);

Error in ==> Dimbeta at 4
[tsMovAv validFromAv] = movAv (tsIn, 1, idays1);

Error in ==> sysdimbeta at 5
[tsDim validFromDim] = dimbeta (tsIn,idays1);

Error in ==> plotSystem at 34
[tsSysOut, tsSysOutPlot] = sysDimbeta(st, tsIn, days1, days2);

??? Error using ==> plotSystem
Error using ==> tsmovavg
Invalid number of inputs.

??? Error while evaluating uicontrol Callback

What's the problem? How can I solve it?

Thank you :)

Re: How to quickly generate list of traversal schemes

Walter Roberson — Fri, 30 Jul 2010 23:25:07 -0400

Jeremy Freeman wrote:
> I have ran into a speed barrier on a piece of code I'm working, and I
> hope some of you guys can offer any advice on my problem.
>
> I have to determine the best way to connect source points to destination
> points for use in a blob tracking algorithm. Because of the non
> descriptive nature of the blobs, I effectively have a list of points for
> the set of destinations and sources. I also have the distances between
> each source and destination pair.
>
> Now, for the problem. I need to find mutually exclusive sets (no
> destination can have a source that another node has, and a source can
> have no destination that another source has). After generating the
> sets, I can determine the weights and pick the best.
>
> I am currently doing this with a brute force method (with a few
> optimizations), but still have serious speed issues on the size of the
> arrays that I am using.
>
> The bottleneck is generating the sets. Any ideas on how to do this faster?

This sounds to me to be possibly equivalent to "The Marriage Problem",
http://www.cut-the-knot.org/arithmetic/marriage.shtml

smoothin a beizer curve

Danna — Fri, 30 Jul 2010 23:22:06 -0400

I have this code, the P1(3,1)(3,2) points are the same as P(1,1)(1,2), and i need to subtitude them to smooth the result

P1=[-5,3;4,-2;3,2];
P=[3,2;5,6;2,4;3,4];
t=0:0.01:1;
X(:,1)=(1-t).^2*P1(1,1)+2*(1-t).*t*P1(2,1)+t.^2*P1(3,1);
X(:,2)=(1-t).^2*P1(1,2)+2*(1-t).*t*P1(2,2)+t.^2*P1(3,2);
plot(X(:,1),X(:,2))
hold on
X1(:,1)=(1-t).^3*P(1,1)+3*(1-t).^2.*t*P(2,1)+3*(1-t).*t.^2*P(3,1)+t.^3*P(4,1);
X1(:,2)=(1-t).^3*P(1,2)+3*(1-t).^2.*t*P(2,2)+3*(1-t).*t.^2*P(3,2)+t.^3*P(4,2);
plot(X1(:,1),X1(:,2))

I tried this, but it didn´t work out:

P1=[-5,3;4,-2;3,2];
P=[3,2;5,6;2,4;3,4];

t=0:0.01:1;
P1(3,1)=(1-t)*P(3,1)+P1(1,1);
P1(3,2)=(1-t)*P(3,2)+P1(1,2);
P(1,1)=(1-t)*P(3,1)+P1(1,1);
P(1,2)=(1-t)*P(3,1)+P1(1,1);

X(:,1)=(1-t).^2*P1(1,1)+2*(1-t).*t*P1(2,1)+t.^2*P1(3,1);
X(:,2)=(1-t).^2*P1(1,2)+2*(1-t).*t*P1(2,2)+t.^2*P1(3,2);
plot(X(:,1),X(:,2))
hold on
X1(:,1)=(1-t).^3*P(1,1)+3*(1-t).^2.*t*P(2,1)+3*(1-t).*t.^2*P(3,1)+t.^3*P(4,1);
X1(:,2)=(1-t).^3*P(1,2)+3*(1-t).^2.*t*P(2,2)+3*(1-t).*t.^2*P(3,2)+t.^3*P(4,2);
plot(X1(:,1),X1(:,2))

what can i do???

thanks

scrollbar/slider for the axes

tunio — Fri, 30 Jul 2010 23:21:04 -0400

hi,
as i mentioned in my previous message that i am using the following code to plot two different types of data on two axes. One of them is 'xls' and the other one is 'ascii'.
now the next task is the implementation of a slider at the horizontal position for the both axes so when i zoom in into the axes and the graph expand then with help of this slider i should move from left to right or right to left along the graph.
i am not very familier to matlab and this is the part of a project which i have to finish in 1 week so i,ll be very thankful if any body can help me in detail for this part of my project.
here are the codes from my m.file

function varargout = ekg_vis(varargin)
gui_Singleton = 1;
gui_State = struct('gui_Name', mfilename, ...
                   'gui_Singleton', gui_Singleton, ...
                   'gui_OpeningFcn', @ekg_vis_OpeningFcn, ...
                   'gui_OutputFcn', @ekg_vis_OutputFcn, ...
                   'gui_LayoutFcn', [] , ...
                   'gui_Callback', []);
if nargin && ischar(varargin{1})
    gui_State.gui_Callback = str2func(varargin{1});
end

if nargout
    [varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
    gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT

file = '';

% --- Executes just before ekg_vis is made visible.
function ekg_vis_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject handle to figure
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% varargin command line arguments to ekg_vis (see VARARGIN)

% Choose default command line output for ekg_vis
handles.output = hObject;

% Update handles structure
guidata(hObject, handles);
set(hObject, 'toolbar','figure');

% This sets up the initial plot - only do when we are invisible
% so window can get raised using ekg_vis.
%if strcmp(get(hObject,'Visible'),'off')
% plot(rand(5));
%end

% UIWAIT makes ekg_vis wait for user response (see UIRESUME)
% uiwait(handles.figure1);

% --- Outputs from this function are returned to the command line.
function varargout = ekg_vis_OutputFcn(hObject, eventdata, handles)
% varargout cell array for returning output args (see VARARGOUT);
% hObject handle to figure
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)

% Get default command line output from handles structure
varargout{1} = handles.output;

% --- Executes on button press in pushbutton1.
function pushbutton1_Callback(hObject, eventdata, handles)
% hObject handle to pushbutton1 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)

sh(1)=subplot(2,1,1);
cla;
file=get(handles.text1,'String');
data = xlsread(file);
data_len = length(data);
plot(data(1:data_len,1));

h = uicontrol('Style', 'pushbutton', 'String', 'Clear Graph/s',...
    'Position', [10 10 103 30], 'Callback', 'cla');

sh(2)=subplot(2,1,2);
cla;
filea=get(handles.text2,'String');
dataascii = textread(filea);
data_lenascii = length(dataascii);
plot(dataascii);

linkaxes(sh,'x');

% --------------------------------------------------------------------
function FileMenu_Callback(hObject, eventdata, handles)
% hObject handle to FileMenu (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)

% --------------------------------------------------------------------
function OpenMenuItem_Callback(hObject, eventdata, handles)
% hObject handle to OpenMenuItem (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
file = uigetfile('*.fig');
if ~isequal(file, 0)
    open(file);
end

% --------------------------------------------------------------------
function PrintMenuItem_Callback(hObject, eventdata, handles)
% hObject handle to PrintMenuItem (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
printdlg(handles.figure1)

% --------------------------------------------------------------------
function CloseMenuItem_Callback(hObject, eventdata, handles)
% hObject handle to CloseMenuItem (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
selection = questdlg(['Close ' get(handles.figure1,'Name') '?'],...
                     ['Close ' get(handles.figure1,'Name') '...'],...
                     'Yes','No','Yes');
if strcmp(selection,'No')
    return;
end

delete(handles.figure1)

% --- Executes on selection change in popupmenu1.
function popupmenu1_Callback(hObject, eventdata, handles)
% hObject handle to popupmenu1 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)

% Hints: contents = get(hObject,'String') returns popupmenu1 contents as cell array
% contents{get(hObject,'Value')} returns selected item from popupmenu1

% --- Executes during object creation, after setting all properties.
function popupmenu1_CreateFcn(hObject, eventdata, handles)
% hObject handle to popupmenu1 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles empty - handles not created until after all CreateFcns called

% Hint: popupmenu controls usually have a white background on Windows.
% See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
     set(hObject,'BackgroundColor','white');
end

set(hObject, 'String', {'plot(rand(5))', 'plot(sin(1:0.01:25))', 'bar(1:.5:10)', 'plot(membrane)', 'surf(peaks)'});

% --- If Enable == 'on', executes on mouse press in 5 pixel border.
% --- Otherwise, executes on mouse press in 5 pixel border or over pushbutton1.
function pushbutton1_ButtonDownFcn(hObject, eventdata, handles)
% hObject handle to pushbutton1 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)

% --- Executes on button press in pushbutton4.
function pushbutton4_Callback(hObject, eventdata, handles)
% hObject handle to pushbutton4 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)

[name path index] = uigetfile('*.xls','Bitte Excel Datei auswählen');
file = strcat(path,name);
set(handles.text1,'String',file);

% --- Executes on button press in pushbuttonacsii.
function pushbuttonacsii_Callback(hObject, eventdata, handles)
% hObject handle to pushbuttonacsii (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)

[name path index] = uigetfile('*.ascii','Bitte ascii Datei auswählen');
file = strcat(path,name);
set(handles.text2,'String',file);

Re: remove

Walter Roberson — Fri, 30 Jul 2010 23:18:50 -0400

Abhishek wrote:

>> > syms A B C D E F G H I J K L M N O P Q R S T U V W X Y Z a b c d e
>> f g h i j k l m n o p q r s t u v w x y z S1 TL1 >

> for k=1:i
> eq(k)=TL1(k+i+2);
> end
> eq1=num2cell(eq);
> TTL1=num2cell(TL1);
> S=solve(eq1{:},TTL1{3:i+2});
> Vout=S.x;
> Vin=z;
> H=Vout/Vin;
> which works but i want to use Vout=S.TTL1{3};
> Vin=S.TTL1{2};
> H=Vout/Vin;
> as it is a part of automation....But it gives error as
> >S.TTL1{3}
> ??? Reference to non-existent field 'TTL1'.

S.(TTL1{3})

Re: fread repetition factor

Ralph Page — Fri, 30 Jul 2010 23:07:21 -0400

Walter Roberson <roberson@hushmail.com> wrote in message <i2vk6a$nu$2@canopus.cc.umanitoba.ca>...
> Ralph Page wrote:
> > I am using:
> > DataValues=fread(fid,'2304*uint8',116);
> > To read in 2304 bytes, then skip 116 bytes and repeat for the entire file.
> > Works great.
> > I'd like to make the 2304 value a variable.
> > So far I have been unsuccessful, is it possible?
>
> DataValues=fread(fid,sprintf('%d*uint8',BytesToRead),116);

Thanks Walter, works great

Re: How do you find all the 0's in a matrix and replace with NaN

Priom Rahman — Fri, 30 Jul 2010 23:02:06 -0400

Brilliant thanks !!!!!!