how to perform wavelet transform on time series speed signal
I have time vs velocity data. This should be used as my time series speed signal on which i have to perform continuous wavelet transform using matlab (wavelet toolbox). But I am not able to incorporate the time component. I am importing signal from workspace which is a nx1 array(velocity). Any clarification on how to incorporate time vs speed as my signal will be great. Thanks in advance...
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Calling a Function in Matlab with Symbolic Functions as Arguments
I have written the following
Matlab
function:function EulerMethod(t_min,t_max,h,f,Y,yzero) tlist = t_min:h:t_max; N = (t_max  t_min)/h; ylist = transpose(zeros(N+1,1)); ylist(1) = yzero; for i=1:N term = f(tlist(i),ylist(i))*h; ylist(i+1) = ylist(i) + term; end yrange = Y(tlist); % modified to generate a new figure window each time. figure; plot(tlist,yrange,'red','LineWidth', 2); hold; plot(tlist,ylist,'blue','LineWidth', 2); plot(tlist, abs(yrange  ylist),'magenta','LineWidth', 2) % modified to wrap the title. title({'Graphs of the True Solution, Euler Solution,', 'and the Absolute Value of the Global Error (GE)'}) xlabel('t') ylabel('Y(t)') legend({'True Solution','Euler Solution', 'Absolute Value of the GE'},'Location','southwest') end
I now try and call this function in another script. The variables
f
andY
in the function are symbolic functions; so, in the other file, I first declare these functions before calling this function. Here's the code:clc syms f(t,y) syms Y(t) f(t,y) = y + 2.0*cos(t); %This the derivative of the function whose solution we're trying to computed Y(t) = sin(t) + cos(t); %This is the true solution; % Calling function EulerMethod(0.0, 6.0, 0.2, f, Y, 1.0);
I, however, get errors when I run the second script. Can anyone help me figure out what's going wrong? I suspect this may be because of the way I have both input and used the symbolic functions
f
andY
but I am not sure. 
How to plot a multidimensional array in matlab?
I have a table as follows
system:index 2017_06_18 2017_06_19 2017_06_20 2017_06_21 2 612.8099664 1174.656713 1282.083251 815.3828357 3 766.4103726 1345.135952 1322.726083 749.998993 4 765.0230453 1411.669136 1350.437586 610.9541838 5 553.5858458 1374.14789 1152.086957 566.7924468 6 466.9780908 1311.903756 1060.494001 559.1982264 7 257.1162602 1270.182385 988.5455285 562.9224932 8 230.6611542 1310.971988 1001.548768 502.3266959
I want to plot a 2dcolormap representing system:index as y axis, dates as x axis and values under dates as colors. I tried with the following code but it did not give what I want.
clear clc filename = 'TurbidityDailyMean.xlsx'; data = xlsread(filename,'TurbidityDailyMean','A1:E8'); figure; hold on for i = 2:5 y = data(:,1); x = data(:,i); plot(x,y) end
I need to map a colormap as mentioned above. But from what I tried it gives something else. And another fact is that I can't insert system:index and dates row into matlab with relevant data.

Regexp syntax MATLAB
input1 = ' 8 BKN 15 BKN ' input2 = ' 2 X 3SM ' regexp(input1, '\s{1}\d(12)\s{1}c{3}\s{1}') regexp(input2, ''\s{1}\d(12)\c{1}\s{1}c{1}\s{1}' )
Have trouble getting regexp to work. I'm not at all great a debugging.
The code needs to identify (one space, (one digit or two digits), one space, three characters
[AZ]
, and one space)The code needs (one space, one digit or two digits, one space, X the letter, one digit and two characters, and one space)

Why I cannot get the same length when I reconstruct the data from wavelet packets by pywt
For example, I tried to reconstruct the data by Node 'aaa' by this code:
q = pywt.WaveletPacket(range(0,100),'db4',mode = 'symmetric') n = pywt.WaveletPacket(None,'db4',mode = 'symmetric') n['aaa'] = q['aaa'] n = n.reconstruct()
But as the result, the length of n is 102, not 100. Why the length changed in reconstructed data?

code for continuous wavelet transform
Do you have a code to make the continuous wavelet transform? I can do it with the Fourier transform. But the fourier transform of my wavelet is not calculable. Here is my wavelet:
$psi(t)=cos(2*\pi*C*ln(1t/D))$ where C and D are real constants