I'm using MATLAB 2013a and trying to find peak points of my data. When I tried code example given in
Find Peaks with Minimum Separation
I am getting the following error:
Error using uddpvparse (line 122)
Invalid Parameter/Value pairs.
Error in findpeaks>parse_inputs (line 84)
hopts = uddpvparse('dspopts.findpeaks',varargin{:});
Error in findpeaks (line 59)
[X,Ph,Pd,Th,Np,Str,infIdx] = parse_inputs(X,varargin{:});
I tried simple x and y vectors and got the same error. What can be the problem?
I have the same problem as you (R2013a on OSX) with the example by the Mathworks. For some reason it seems we can't use findpeaks with the x-and y-data as input arguments, We need to call the function with the y data and use the [peaks,locations] output to get the peaks/plot them.
It looks like in R2014b they changed some stuff about findpeaks that does not work with older versions...like calling the function with not output argument in R2014b plots the data/peaks without any additional step...but it does not for earlier versions.
Anyhow here is a way to workaround the problem. Call findpeaks with a single input argument (y data that is, you can use property/value pairs as well) and use the indices (locations) to show the peaks:
clc
clear
load sunspot.dat
year = sunspot(:,1);
avSpots = sunspot(:,2);
[peaks, locations] = findpeaks(avSpots)
plot(year,avSpots)
hold on
scatter(year(locations),avSpots(locations),40,'filled')
hold off
Output:
It might be worthwhile to contact The Mathworks about this. Hope that helps!
Related
Today I tried to run a MATLAB m-file that someone gave me. It works fine for him, but I encountered a warning and errors (below). I am using a Mac with OS X Yosemite (10.10.5) and a new version of MATLAB (R2015b). The person who prepared the m-file would have used an older one and Windows.
From a blog at Mathworks and posts online/here, the error seems to be due to a MATLAB update--a change from using numeric values to point towards graphics objects to using objects themselves. I understand this in theory, but don't know how to fix my code (it has been years since I used MATLAB regularly, so I'm pretty lost).
Warning: Text handle output is not supported when a contour handle
argument is supplied and label placement is automatic.
In clabel (line 214)
In control_volume_20150706>plot_xxx (line 733)
In control_volume_20150706 (line 104)
In run (line 96)
Error using sprintf
Function is not defined for
'matlab.graphics.GraphicsPlaceholder' inputs.
Error in control_volume_20150706>plot_xxx (line 734)
sprintf('%10.4f \n',text_handle);
Error in control_volume_20150706 (line 104) plot_xxx (nr,
xwidevec, yhighvec, omegamat, psimat, umat, vmat, ...
Error in run (line 96) evalin('caller', [script ';']);
This is what the code looks like in the vicinity of line 733:
Line 731 contourlevels = omegamat(1, :) ;
Line 732 [C,h] = contour(X,
Y, flipud(omegamat), contourlevels, 'LineWidth', 2 );
Line 733
text_handle = clabel(C,h);
Line 734 sprintf('%10.4f \n',text_handle);
I would be very grateful for any hints about how to deal with this.
If h is a handle which refers to some object, then in R2015a and later this is the object itself, while in previous versions it's a double which points to an object (as you noted in the question). You can use h.double in R2015a and later to get what would previously be h. E.g., pre-R2015a h = figure(999) would set h to 999, a double; with R2015a and later h is an object and h.double is 999.
I have several sets of data that I want to fit but not all of them look the same (some look like a Gaussian with one peak, some like two Gaussians with 2 peaks or Lorentzians). I wanted to try this method
http://www.mathworks.com/matlabcentral/fileexchange/31562-data-driven-fitting-with-matlab/content/fitit.m
but the program given is not complete so I can not use it (there is no line that defines 'train' and 'test'). I am writing it so that it suits and works for my data (based on the code that it is given and the demo). I was able to find the best fit but I am also trying to use the bootstrap technique in order to find the confidence intervals. My data is xdata and ydata and they are sorted and the duplicates have been removed before I use them in my program.
cpart=cvpartition(size(xdata,1),'k',10);
tr_x=xdata(training(cpart,1));
tr_y=ydata(training(cpart,1));
tst_x=xdata(test(cpart,1));
tst_y=ydata(test(cpart,1));
all_span=linspace(0.01,0.99,99);
s=zeros(length(all_span);
for k=1:length(all_span)
f = #(tr_x,tr_y,tst_x,tst_y) norm(tst_y mylowess (tr_x, tr_y, tst_x, all_span (k)))^2
s(k) = sum(crossval(f,datax,datay,'partition',cpart));
end
[~,mj]=min(s);
n_span=all_span(mj);%n_span is the optimal span
function ys=mylowess(x1,y1,xs,span)
ys1 = smooth(x1,y1,span,'loess');
ys = interp1(x1,ys1,xs,'linear',NaN);
if any(isnan(ys))
ys(xs<x1(1)) = ys1(1);
ys(xs>x1(end)) = ys1(end);
end
So up to this point I understand the program and I have managed to find the optimal span. I want to find the confidence intervals but so far I was not able to make it work.
When I type:
NB=length(xdata);
f=#(xdata,ydata) mylowess(xdata,ydata,xdata,n_span);
yboot2 = bootstrp(NB,f,xdata,ydata)';
I get the following error
Error using griddedInterpolant
The grid vectors are not strictly monotonic increasing.
Error in interp1 (line 186)
F = griddedInterpolant(X,V,method);
Error in mylowess (line 26)
ysmooth=interp1(xdata,ysmooth1,xinput,'linear',NaN);
As I said before there are no duplicates in xdata and I have already sorted xdata before I used them in the program. Can anyone see the mistake I am making? Or is there an easier way to get the confidence intervals?
Thank you for your help.
I'm trying to use getpts to get the location of the selected points by the user.
I used it as follows:
[X,Y] = getpts(imread('xyz.jpg'));
But, got the following error:
Error using getpts (line 46)
First argument is not a valid handle.
Error in program (line 7)
[X,Y] = getpts(imread('xyz.jpg'));
Why is that?
Thanks.
getpts needs a handle to either a figure or an axes, not a matrix as given by imread.
The simple solution is to display the image, then input either gca or gcf to getpts. Or you can manage handles on your own, but I don't think you wan't to do that.
Or to put it on one line with imshow:
[X,Y] = getpts(get(imshow('xyz.jpg'),'Parent'));
Using the adftest function in MATLAB's econometrics toolbox, I'm receiving the following error:
>> [h1,pVal1] = adftest(y1,'model','ARD')
Error using lagmatrix (line 25)
lagmatrix: wrong # of input arguments
Error in adftest>runReg (line 705)
yLags = lagmatrix(y,0:(testLags+1));
Error in adftest (line 417)
testReg = runReg(i,y,testT,testLags,testModel,needRegOut);
y1 is a <41x1> vector of doubles.
Has anyone received this error or have any thoughts on what the issue is? I am using this code right out of the box so I'm not sure what is going on. I'd post to MATLAB's site, but it is down for maintenance.
This is either a bug in Matlab, in which case you should submit it on the Matlab support site. Before you do that, you should check that you don't have a function lagmatrix on your path that shadows the built-in function. Type
which lagmatrix
on the command line. If the path does not point to your Matlab installation, you should move lagmatrix off the Matlab search path.
Also note that y1 should not contain all NaN, or be otherwise degenerate, so you may want to check the function using the sample data as suggested in the help to be sure it's a bug and not just your data.
I had the same problem with this function. In my case, the problem was the function lagmatrix (older version) in my MATLAB path and the adftest function was the newest version. The soluction was delete the older version of lagmatrix.
I have a simple function written
function[] = myfun(p,q)
fminbnd(#(x)myfun1(q,p,b),0,1)
where myfun1's output is from the function quad.
How do I plot myfun? I've tried fplot(#(x)myfun(1,x),0,1) but this gives me a matrix dimensions must agree error...
Your question does not contain enough information to identify exactly where the problem lies, but one issue is certainly that myfun does not return any output. What should fplot plot, if there is nothing returned by the function?
Try
function out = myfun(p,q)
%# you may want to define b here
out = fminbnd(#(x)myfun1(q,p,b),0,1);
If that doesn't fix the issue, turn on the debugging mode by typing dbstop if error at the command line. This will show where exactly the error occurs, and allow you to inspect the variables for correct shape.