


fits significant sine waves to data (continuous data).
Usage: [datafit,Amps,freqs,Fval,sig]=fitlinesc(data,f0,params,p,plt)
Inputs:
Note that units of Fs, fpass have to be consistent.
data (data in [N,C] i.e. time x channels/trials or a single vector) - required.
f0 a single frequency at which you want to remove the
lines - specify empty [] if you just want the program
to compute the significant lines
params structure containing parameters - params has the
following fields: tapers, Fs, fpass, pad
tapers (parameters for calculating tapers [NW,K]) - optional. Defaults to [3 5]
Fs (sampling frequency) -- optional. Defaults to 1.
fpass (frequency band to be used in the calculation in the form
[fmin fmax])- optional.
Default all frequencies between 0 and Fs/2
pad (padding factor for the FFT) - optional. Defaults to 0.
e.g. For N = 500, if PAD = 0, we pad the FFT
to 512 points; if PAD = 2, we pad the FFT
to 2048 points, etc.
p (P-value to calculate error bars for) - optional. Defaults to 0.05/N where N is data length.
plt (y/n for plot and no plot respectively) - plots the
Fratio at all frequencies if y
Outputs:
datafit (linear superposition of fitted sine waves)
Amps (amplitudes at significant frequencies)
freqs (significant frequencies)
Fval (Fstatistic at all frequencies)
sig (significance level for F distribution p value of p)

0001 function [datafit,Amps,freqs,Fval,sig]=fitlinesc(data,f0,params,p,plt) 0002 % fits significant sine waves to data (continuous data). 0003 % 0004 % Usage: [datafit,Amps,freqs,Fval,sig]=fitlinesc(data,f0,params,p,plt) 0005 % 0006 % Inputs: 0007 % Note that units of Fs, fpass have to be consistent. 0008 % data (data in [N,C] i.e. time x channels/trials or a single vector) - required. 0009 % f0 a single frequency at which you want to remove the 0010 % lines - specify empty [] if you just want the program 0011 % to compute the significant lines 0012 % params structure containing parameters - params has the 0013 % following fields: tapers, Fs, fpass, pad 0014 % tapers (parameters for calculating tapers [NW,K]) - optional. Defaults to [3 5] 0015 % Fs (sampling frequency) -- optional. Defaults to 1. 0016 % fpass (frequency band to be used in the calculation in the form 0017 % [fmin fmax])- optional. 0018 % Default all frequencies between 0 and Fs/2 0019 % pad (padding factor for the FFT) - optional. Defaults to 0. 0020 % e.g. For N = 500, if PAD = 0, we pad the FFT 0021 % to 512 points; if PAD = 2, we pad the FFT 0022 % to 2048 points, etc. 0023 % p (P-value to calculate error bars for) - optional. Defaults to 0.05/N where N is data length. 0024 % plt (y/n for plot and no plot respectively) - plots the 0025 % Fratio at all frequencies if y 0026 % 0027 % 0028 % Outputs: 0029 % datafit (linear superposition of fitted sine waves) 0030 % Amps (amplitudes at significant frequencies) 0031 % freqs (significant frequencies) 0032 % Fval (Fstatistic at all frequencies) 0033 % sig (significance level for F distribution p value of p) 0034 data=change_row_to_column(data); 0035 [N,C]=size(data); 0036 if nargin < 3 || isempty(params); params=[]; end; 0037 [tapers,pad,Fs,fpass,err,trialave,params]=getparams(params); 0038 clear pad fpass err trialave 0039 if nargin<4;p=0.05/N;end; 0040 params.tapers=dpsschk(tapers,N,Fs); % calculate the tapers 0041 [Fval,A,f,sig] = ftestc(data,params,p,plt); 0042 if isempty(f0); 0043 fmax=findpeaks(Fval,sig); 0044 freqs=cell(1,C); 0045 Amps=cell(1,C); 0046 datafit=data; 0047 for ch=1:C; 0048 fsig=f(fmax(ch).loc); 0049 freqs{ch}=fsig; 0050 Amps{ch}=A(fmax(ch).loc,ch); 0051 Nf=length(fsig); 0052 fprintf('The significant lines for channel %d and the amplitudes are \n',ch); 0053 for nf=1:Nf; 0054 fprintf('%12.8f\n',fsig(nf)); 0055 fprintf('%12.8f\n',real(A(fmax(ch).loc(nf),ch))); 0056 fprintf('%12.8f\n',imag(A(fmax(ch).loc(nf),ch))); 0057 fprintf('\n'); 0058 end; 0059 datafit(:,ch)=exp(i*2*pi*(0:N-1)'*fsig/Fs)*A(fmax(ch).loc,ch)+exp(-i*2*pi*(0:N-1)'*fsig/Fs)*conj(A(fmax(ch).loc,ch)); 0060 end; 0061 else; 0062 [fsig,indx]=min(abs(f-f0)); 0063 fsig=f(indx); 0064 for ch=1:C; 0065 freqs{ch}=fsig; 0066 Amps{ch}=A(indx,ch); 0067 Nf=length(fsig); 0068 fprintf('For channel %d the amplitudes and the Fstatistic at f=%f are \n',ch,f0); 0069 fprintf('Fstatistic = %12.8f Fthreshold = %12.8f\n',Fval(indx),sig); 0070 fprintf('Real part of amplitude = %12.8f\n',real(A(indx,ch))); 0071 fprintf('Imaginary part of amplitude = %12.8f\n',imag(A(indx,ch))); 0072 datafit(:,ch)=exp(i*2*pi*(0:N-1)'*fsig/Fs)*A(indx,ch)+exp(-i*2*pi*(0:N-1)'*fsig/Fs)*conj(A(indx,ch)); 0073 end; 0074 end; 0075