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Tools.cc
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Tools.cc
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#include <cmath>
#include <fstream>
#include <iostream>
#include <vector>
#include "Tools.h"
#include "TSpline.h"
#include "TH2F.h"
#include "Constants.h"
#include <boost/math/interpolators/whittaker_shannon.hpp>
// fft related
#include "FFTtools.h"
#include <fftw3.h>
using std::cout;
void Tools::MakeGraph(const int n,double *time,double *volts,TGraph *&mygraph,TH2F *&h2, double scalex,double scaley,string xaxistitle,string yaxistitle) {
double maxtime=-1.E20;
double maxv=-1.E20;
double mintime=1E20;
double minv=1.E20;
double timecopy[n];
double voltscopy[n];
for (int i=0;i<n;i++) {
timecopy[i]=time[i];
voltscopy[i]=volts[i];
timecopy[i]*=scalex;
voltscopy[i]*=scaley;
}
for (int i=0;i<n;i++) {
if (timecopy[i]>maxtime)
maxtime=timecopy[i];
if (timecopy[i]<mintime)
mintime=timecopy[i];
if (voltscopy[i]>maxv)
maxv=voltscopy[i];
if (voltscopy[i]<minv)
minv=voltscopy[i];
}
mygraph=new TGraph(n,timecopy,voltscopy);
h2=new TH2F("h2","",10*n,mintime*1.1,maxtime*1.1,100,minv*1.1,maxv*1.1);
h2->SetLineWidth(3);
h2->SetXTitle(xaxistitle.c_str());
h2->SetYTitle(yaxistitle.c_str());
}
int Tools::iSum(int* thisarray,int n) {
int sum=0;
for (int i=0;i<n;i++) {
sum+=thisarray[i];
} //for
return sum;
} //iSum
double Tools::getMaxMagnitude(vector<double> v) {
double mag=0.;
for (int i=0;i<(int)v.size();i++) {
if (v[i]>mag)
mag=v[i];
}
return mag;
}
void Tools::ShiftLeft(double *x,const int n,int ishift) {
double x_temp[n];
// shift the x array to the left by ishift bins and fill the gap with zeroes
for (int i=0;i<n;i++) {
x_temp[i]=x[i];
}
for (int i=0;i<n-ishift;i++) {
x[i]=x_temp[i+ishift];
}
for (int i=n-ishift;i<n;i++) {
x[i]=0.;
}
}
void Tools::ShiftRight(double *x,const int n,int ishift) {
double x_temp[n];
// shift the x array to the right by ishift bins and fill the gap with zeroes
for (int i=0;i<n;i++) {
x_temp[i]=x[i];
}
for (int i=ishift;i<n;i++) {
x[i]=x_temp[i-ishift];
}
for (int i=0;i<ishift;i++) {
x[i]=0.;
}
}
//! A function to do FFT
/*!
The function performs the FFT on an array data of size nsize
\param data the data to be transformed
\param isign whether you want a forward (1) or reverse (-1) transform
\param nsize size of the array to be transformed (must be a factor 2!)
\return void
*/
void Tools::realft(double *data, const int isign, int nsize){
/*
* This function was specifically engineered by Yuchieh Ku
* to emulate the interface of the numerical recipes "realft" function
* This function has exactly the same input and output formats as the "realft" function in the numerical recipes.
* Input array {f1,f2,f3....f_nsize}, after this fcn, it will become {F_0, F_N/2, F_1_r, F_1_c, F_2_r, F_2_c,...} (Forward).
* isign: 1/-1 Forward/Inverse FFT.
* For forward FFT, complex conjugate is taken since isign convention is opposite in numerical recipes.
* Inverse FFT has a N/2 normalization factor.
*/
if(isign==1){
FFTWComplex *fftarray;
fftarray=FFTtools::doFFT(nsize,data);
format_transform(nsize, 1, (fftw_complex*)fftarray, data);
delete [] fftarray;
}
else if(isign==-1){
fftw_complex *fftarray;
fftarray=(fftw_complex*) fftw_malloc(sizeof(fftw_complex) * (nsize/2+1));
format_transform(nsize,-1,fftarray, data);
double* invfft;
invfft=FFTtools::doInvFFT(nsize, (FFTWComplex*)fftarray);
for(int i=0;i<nsize;i++)
data[i]=invfft[i]*nsize/2;
free(fftarray);
delete [] invfft;
}
}
void Tools::format_transform(int nsize, int trdir, fftw_complex *out, double *data){
if(trdir==1){
for(int i=0;i<nsize;i++){
if(i%2){
data[i]=(-1)*out[i/2][i%2];
}
else{
data[i]=out[i/2][i%2];
}
}
data[1]=out[nsize/2][0];
}else if(trdir==-1){
for(int i=2;i<nsize;i++){
if(i%2){
out[i/2][i%2]=(-1)*data[i];
}
else {
out[i/2][i%2]=data[i];
}
}
out[0][0]=data[0];
out[0][1]=0;
out[nsize/2][0]=data[1];
out[nsize/2][1]=0;
}
}
double Tools::dSquare(double *p) {
return p[0]*p[0]+p[1]*p[1]+p[2]*p[2];
} //dSquare
int Tools::WhichIsMin(double *x,int n) {
double min=1.E22;
int imin=0;
for (int i=0;i<n;i++) {
if (x[i]<min) {
min=x[i];
imin=i;
}
} //for
return imin;
} //WhichIsMin
void Tools::Print(double *p,int i) {
for (int j=0;j<i;j++) {
cout << p[j] << " ";
} //for
cout << "\n";
} //Print (double*,int)
void Tools::Print(int *p,int i) {
for (int j=0;j<i;j++) {
cout << p[j] << " ";
} //for
cout << "\n";
} //Print (double*,int)
void Tools::GetNextNumberAsString(ifstream& fin,ofstream& fout,string& number) {
string temp;
getline(fin,temp); // get next line of the input file
fout << temp << "\n"; // output this line to the summary file
int place=0;
place=temp.find_first_of(" \t"); // find where the first space or tab is
number=temp.substr(0,place); // everything up until the first space is what we're looking for
} //GetNextNumberAsString
void Tools::GetNumbersAsStringArray(ifstream& fin, ofstream& fout,vector<string>& vnumbers, int nelements) {
string temp;
// getline(fin,temp);
// fout << temp << "\n";
// int place_previous=0;
// int place_next;
vnumbers.clear();
string s;
for (int n=0;n<nelements;n++) {
fin >> s;
fout << s << "\t"; // output this line to the summary file
vnumbers.push_back(s);
// place_next=temp.find_first_of("\t",place_previous+1); // find where first tab is
//vnumbers.push_back(temp.substr(place_previous,place_next-place_previous));
//place_previous=place_next;
}
getline(fin,temp);
fout << temp << "\n";
// cout << "temp is " << temp << "\n";
}
void Tools::GetNext2NumbersAsString(ifstream& fin,ofstream& fout,string& number1,string& number2, string& stherest) {
string temp;
getline(fin,temp); // get next line of the input file
fout << temp << "\n"; // output this line to the summary file
int place=0;
place=temp.find_first_of(" \t"); // find where the first space is
number1=temp.substr(0,place); // everything up until the first space is what we're looking for
temp=temp.substr(place+1,temp.size());
number2=temp.substr(0,temp.find_first_of(" "));
stherest=temp.substr(2,temp.size());
} //GetNext2NumbersAsString
double Tools::GetFWHM(TH1 *h1) {
int imax=h1->GetMaximumBin();
double max=h1->GetMaximum();
// cout << "imax, max are " << imax << " " << max << "\n";
int ibin_plus=0;
int ibin_minus=0;
// now step to the right until it's half
for (int ibin=imax;ibin<=h1->GetNbinsX();ibin++) {
if (h1->GetBinContent(ibin)<max/2.) {
ibin_plus=ibin;
ibin=h1->GetNbinsX()+1;
// cout << "ibin_plus is " << ibin_plus << "\n";
}
}
// now step to the left
for (int ibin=imax;ibin>=1;ibin--) {
if (h1->GetBinContent(ibin)<max/2.) {
ibin_minus=ibin;
ibin=0;
// cout << "ibin_minus is " << ibin_minus << "\n";
}
}
if (ibin_plus>0 && ibin_minus==0) {
ibin_minus=1;
//cout << "bin_minus is " << ibin_minus << "\n";
}
if (ibin_plus==0 && ibin_minus==0) {
cout << "Found 0 FWHM.\n";
return 0.;
}
return (h1->GetBinCenter(ibin_plus)-h1->GetBinCenter(ibin_minus))/2.;
}
void Tools::Zero(int *anarray,int n) {
for (int i=0;i<n;i++) {
anarray[i]=0;
} //for
} //Zero (int*,int)
void Tools::Zero(double *anarray,int n) {
for (int i=0;i<n;i++) {
anarray[i]=0.;
} //for
} //Zero (int*,int)
double Tools::dMinNotZero(const double *x,int n) {
double min=dMax(x,n);
if (min==0)
cout << "max is 0.\n";
for (int k=1;k<n;k++) {
if (x[k]<min && x[k]!=0)
min=x[k];
}
return min;
} //dMinNotZero(double*, int)
double Tools::dMin(const double *x,int n) {
double min=x[0];
for (int k=1;k<n;k++) {
if (x[k]<min)
min=x[k];
}
return min;
} //dMin(double*, int)
double Tools::dMin(double x,double y) {
double min=1.E22;
if (x<y)
min=x;
else
min=y;
return min;
} //dMin(double,double)
double Tools::dMax(const double *x,int n) {
double max=x[0];
for (int k=1;k<n;k++) {
if (x[k]>max)
max=x[k];
}
return max;
} //dMax(double*, int)
double Tools::dvMax(const vector<double> x) {
double max=x[0];
for (int k=1;k<(int)x.size();k++) {
if (x[k]>max)
max=x[k];
}
return max;
} //dMax(double*, int)
double Tools::dsMax(TSpline5 *sp) {
vector<double> y;
double maxn;
double blah1,blah2;
for (int i=0;i<sp->GetNp();i++) {
sp->GetKnot(i,blah1,blah2);
y.push_back(blah2);
}
maxn=Tools::dvMax(y);
return maxn;
}
double Tools::dMax(double a,double b) {
if (a>b)
return a;
else if (a<b)
return b;
else if (a==b)
return a;
return 0;
} //dMax(double,double
int Tools::Getifreq(double freq,double freq_low,double freq_high,int n) {
if (freq>=freq_high)
return -1;
if (freq<freq_low)
return -1;
return (int)((freq-freq_low)/(freq_high-freq_low)*(double)n);
} //Getifreq
void Tools::InterpolateComplex(double *array, const int n) {
// to get rid of the zero bins
double previous_nonzero=0.;
double next_nonzero=0.;
double check;
int ifirstnonzero=0;
int ilastnonzero=0;
int k;
int m=0;
int count_nonzero=0;
// find the first nonzero even element
while (array[2*m]==0) {
m++;
}
ifirstnonzero=m;
// count the nonzero elements
for (int i=0;i<n;i++) {
if (array[2*i]!=0)
count_nonzero++;
}
if (count_nonzero!=0) {
// loop through the elements of the array and replace the zeros with interpolated values
for (int i=ifirstnonzero;i<n;i++) {
if (array[2*i]!=0.) {
// set the lower nonzero value that we are interpolating from
previous_nonzero=array[2*i];
}
else {
check=0.;
k=i;
while (check==0. && k<n) {
check=array[2*k];
k++;
}
if (k<n) {
next_nonzero=check;
for (int j=i;j<k;j++) {
array[2*j]=previous_nonzero+(next_nonzero-previous_nonzero)*(double)(j-(i-1))/(double)(k-(i-1));
array[2*j+1]=array[2*j];
}
i=k-1;
previous_nonzero=next_nonzero;
}
else {
ilastnonzero=i-1;
i=n;
}
} // end if array=0
} // end loop over i
//if (inu==49416)
//cout << "inu, count_nonzero, diff are " << inu << " " << count_nonzero << " " << ilastnonzero << " " << ifirstnonzero << "\n";
//cout << "factor is " << (double)count_nonzero/(double)(ilastnonzero-ifirstnonzero) << "\n";
for (int j=0;j<n;j++) {
array[2*j]*=sqrt((double)count_nonzero/(double)(ilastnonzero-ifirstnonzero));
array[2*j+1]*=sqrt((double)count_nonzero/(double)(ilastnonzero-ifirstnonzero));
}
}
}
void Tools::NormalTimeOrdering(const int n,double *volts) {
double volts_temp[n];
for (int i=0;i<n/2;i++) {
volts_temp[i]=volts[i+n/2];
volts_temp[i+n/2]=volts[i];
}
for (int i=0;i<n;i++) {
volts[i]=volts_temp[i];
}
}
void Tools::NormalTimeOrdering_InvT(const int n,double *volts) {
double volts_temp[n];
for (int i=0;i<n/2;i++) {
volts_temp[i]=volts[i+n/2];
volts_temp[i+n/2]=volts[i];
}
for (int i=0;i<n;i++) {
volts[i]=volts_temp[n-i-1]; // inverse time
}
}
//! A function to do sinc interpolation from time basis of x1 to the time basis of x2
/*!
The function takes an input array (defined by n1, x1, y1), and interpolates
that data to a new time base, provided by x2, and puts the values into y2.
The user must therefore provide the number of input samples (n1)
and the x and y values of the data to be interpolated (x1, y1).
The user must also provide the number of points at which they would like
the function interpolated (n2) and the x-values where the function is to be
interpolation (x2). The content of y2[i] will be replaced with the interpolated values.
\param n1 number of points in the input array
\param x1 array of points representing the x-values of the input array
\param y1 array of points representing the y-values of the input array
\param n2 number of points in the output array
\param x1 array of points representing the x-values of the output array
\param y1 array of points representing the y-values of the output array
\return void
*/
void Tools::SincInterpolation(int n1, double *x1, double *y1, int n2, double *x2, double *y2){
/*
* The Whittaker-Shannon interpolator is useful in the case of band-limited data.
* Otherwise known as "sinc" interpolation, it protects the fidelity of the frequency spectrum of the signal.
* Unlike, say, cubic-spline interpolation--which is faster, but can leave artifacts.
* See https://en.wikipedia.org/wiki/Whittaker–Shannon_interpolation_formula for information,
* and https://www.boost.org/doc/libs/1_71_0/libs/math/doc/html/math_toolkit/whittaker_shannon.html
* for implementation details from the boost documentation.
* This method is slower than linear or spline interpolation--so its use is probably
* probably not ideal/necessary in cases where preserving spectral shape is not important.
*/
// the whittaker-shannon method likes the data to be in a vector
size_t num_input_samps = n1;
std::vector<double> input_y(num_input_samps);
for(size_t samp=0; samp<num_input_samps; samp++){
input_y[samp] = y1[samp];
}
double t0 = x1[0];
double dT = x1[1]-x1[0];
double first_input_sample = x1[0];
double last_input_sample = x1[n1-1];
auto interpolator = boost::math::interpolators::whittaker_shannon<std::vector<double>>(std::move(input_y), t0, dT);
for(int samp=0; samp<n2; samp++){
// check if the sample comes before the first sample of the input array (x1[0])
// or after the last sample of the input array (x1[n1-1])
// if so, then we are asking for the function to *extrapolate*, not *interpolate*
// just use the first/last sample, which replicates the behavior in SimpleLinearInterpolation_OutZero
if(x2[samp]<first_input_sample){
// before first sample, use first sample y1
y2[samp] = y1[0];
}
else if(x2[samp]>last_input_sample){
// after last sample, use last sample of y1
y2[samp] = y1[n1-1];
}
else{
// in the range of support, do interpolation
y2[samp] = interpolator(x2[samp]);
}
}
}
void Tools::SimpleLinearInterpolation(int n1, double *x1, double *y1, int n2, double *x2, double *y2 ) { // reads n1 array values x1, y1 and do simple linear interpolation and return n2 array with values x2, y2.
// if interploated array has wider range (x values) than original array, it will use the first original value
//
int first=0; // first x2 array which is bigger than x1[0]
int last=0; // last x2 array which is smaller than x1[n1-1]
int cnt = 0;
for (int i=0; i<n2; i++) {
if (x2[i] < x1[0] ) {
first++;
}
else if (x2[i] > x1[n1-1]) {
last++;
}
}
for (int i=0; i<n2; i++) {
if (i<first) { // if x2 has smaller x values than x1, just use x1[0] value
y2[i] = y1[0];
}
else if (i>n2-last-1) { // if x2 has bigger x values than x1, just use x1[n1-1] value
y2[i] = y1[n1-1];
}
else {
cnt=-1;
for (int j=0; j<n1; j++) {
//if (x2[i] < x1[j] && cnt==-1) {
if (x2[i] <= x1[j] && cnt==-1) {
cnt = j;
}
}
y2[i] = y1[cnt-1] + (x2[i]-x1[cnt-1])*(y1[cnt]-y1[cnt-1])/(x1[cnt]-x1[cnt-1]);
}
}
}
void Tools::SimpleLinearInterpolation_OutZero(int n1, double *x1, double *y1, int n2, double *x2, double *y2 ) { // reads n1 array values x1, y1 and do simple linear interpolation and return n2 array with values x2, y2.
// if interploated array has wider range (x values) than original array, it will use the first original value
//
int first=0; // first x2 array which is bigger than x1[0]
int last=0; // last x2 array which is smaller than x1[n1-1]
int cnt = 0;
for (int i=0; i<n2; i++) {
if (x2[i] < x1[0] ) {
first++;
}
else if (x2[i] > x1[n1-1]) {
last++;
}
}
for (int i=0; i<n2; i++) {
if (i<first) { // if x2 has smaller x values than x1, just use x1[0] value
//y2[i] = y1[0];
y2[i] = 0.;
}
else if (i>n2-last-1) { // if x2 has bigger x values than x1, just use x1[n1-1] value
//y2[i] = y1[n1-1];
y2[i] = 0.;
}
else {
cnt=-1;
//for (int j=0; j<n1; j++) {
for (int j=1; j<n1; j++) {
//if (x2[i] < x1[j] && cnt==-1) {
if (x2[i] <= x1[j] && cnt==-1) {
cnt = j;
}
}
y2[i] = y1[cnt-1] + (x2[i]-x1[cnt-1])*(y1[cnt]-y1[cnt-1])/(x1[cnt]-x1[cnt-1]);
// test
// if y2[i] goes outside y1[cnt] and y1[cnt-1] range (which should not)
if ( ( y2[i] > y1[cnt] && y2[i] > y1[cnt-1] ) ||
( y2[i] < y1[cnt] && y2[i] < y1[cnt-1] ) ) {
cout<<"SimpleLinearInterpolation bug?! y2["<<i<<"] : "<<y2[i]<<" where y1["<<cnt<<"] : "<<y1[cnt]<<", y1["<<cnt-1<<"] : "<<y1[cnt-1]<<std::endl;
}
}
}
}
double Tools::SimpleLinearInterpolation_extend_Single(int n1, double *x1, double *y1, double x2 ) { // reads n1 array values x1, y1 and do simple linear interpolation and return y2 value
int first=0; // first x2 array which is bigger than x1[0]
int last=0; // last x2 array which is smaller than x1[n1-1]
int cnt = 0;
double slope_1;
double slope_2;
slope_1 = (y1[1] - y1[0]) / (x1[1] - x1[0]);
slope_2 = (y1[n1-1] - y1[n1-2]) / (x1[n1-1] - x1[n1-2]);
double y2;
if ( x2 < x1[0] ) { // if x2 has smaller x values
y2 = slope_1 * (x2 - x1[0]) + y1[0];
}
else if ( x2 > x1[n1-1] ) {
y2 = slope_2 * (x2 - x1[n1-1]) + y1[n1-1];
}
else { // in between
cnt=-1;
for (int j=0; j<n1; j++) {
//if (x2[i] < x1[j] && cnt==-1) {
if (x2 <= x1[j] && cnt==-1) {
cnt = j;
}
}
y2 = y1[cnt-1] + (x2-x1[cnt-1])*(y1[cnt]-y1[cnt-1])/(x1[cnt]-x1[cnt-1]);
}
return y2;
}
void Tools::get_random_rician(double signal_amplitude, double signal_phase, double sigma, double &litude, double &phase){
double rand_gauss_a, rand_gauss_b;
get_circular_bivariate_normal_random_variable(rand_gauss_a, rand_gauss_b);
// check the value
//cout<<"Factor from random rician : "<<sqrt(rand_gauss_a * rand_gauss_a +rand_gauss_b *rand_gauss_b) * sqrt(2./M_PI)<<"\n";
// Gives the gaussian-distributed random variables a standard deviation of sigma
rand_gauss_a *= sigma;
rand_gauss_b *= sigma;
// Gives the gaussian-distributed random variables a mean of (v*cos(theta), v*sin(theta)) when v is the mean of the desired rician distribution
rand_gauss_a += signal_amplitude * cos(signal_phase);
rand_gauss_b += signal_amplitude * sin(signal_phase);
// The Rician Distribution produces the probability of the the absolute value (radius) of a circular bivariate normal random variable:
amplitude = sqrt(rand_gauss_a * rand_gauss_a + rand_gauss_b * rand_gauss_b);
// Thus, the descriptor other than amplitude for the circular bivariate is given by a phase:
phase = atan2(rand_gauss_b, rand_gauss_a);
return;
}
void Tools::get_circular_bivariate_normal_random_variable(double& rand_gauss_a, double& rand_gauss_b){
double rand_uni_a = gRandom->Rndm(); //gRandom->Rndm() produces uniformly-distributed floating points in ]0,1]
double rand_uni_b = gRandom->Rndm();
// Box-Muller transform from a bivariate uniform distribution from 0 to 1 to a gaussian with mean = 0 and sigma = 1
rand_gauss_a = sqrt(-2. * log(rand_uni_a)) * cos(2. * M_PI * rand_uni_b);
rand_gauss_b = sqrt(-2. * log(rand_uni_a)) * sin(2. * M_PI * rand_uni_b);
return;
}
void Tools::Exchange( double &a, double &b ) {
double tmp = a;
a = b;
b = tmp;
}