]> git.donarmstrong.com Git - mothur.git/blobdiff - linearalgebra.cpp
changing command name classify.shared to classifyrf.shared
[mothur.git] / linearalgebra.cpp
index 2e0321e53bb8f601fcaff916db5534cc217709be..cd2ca0397bb21493761c69f729893103fc314613 100644 (file)
@@ -8,8 +8,15 @@
  */
 
 #include "linearalgebra.h"
+#include "wilcox.h"
 
 // This class references functions used from "Numerical Recipes in C++" //
+
+/*********************************************************************************************************************************/
+inline double SQR(const double a)
+{
+    return a*a;
+}
 /*********************************************************************************************************************************/
 
 inline double SIGN(const double a, const double b)
@@ -17,6 +24,235 @@ inline double SIGN(const double a, const double b)
     return b>=0 ? (a>=0 ? a:-a) : (a>=0 ? -a:a);
 }
 /*********************************************************************************************************************************/
+//NUmerical recipes pg. 245 - Returns the complementary error function erfc(x) with fractional error everywhere less than 1.2 × 10−7.
+double LinearAlgebra::erfcc(double x){
+    try {
+        double t,z,ans;
+        z=fabs(x);
+        t=1.0/(1.0+0.5*z); 
+        
+        ans=t*exp(-z*z-1.26551223+t*(1.00002368+t*(0.37409196+t*(0.09678418+
+            t*(-0.18628806+t*(0.27886807+t*(-1.13520398+t*(1.48851587+
+            t*(-0.82215223+t*0.17087277))))))))); 
+        
+        //cout << "in erfcc " << t << '\t' << ans<< endl;
+        return (x >= 0.0 ? ans : 2.0 - ans);
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "betai");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+//Numerical Recipes pg. 232
+double LinearAlgebra::betai(const double a, const double b, const double x) {
+    try {
+        double bt;
+        double result = 0.0;
+        
+        if (x < 0.0 || x > 1.0) { m->mothurOut("[ERROR]: bad x in betai.\n"); m->control_pressed = true; return 0.0; }
+        
+        if (x == 0.0 || x == 1.0)  { bt = 0.0; }
+        else { bt = exp(gammln(a+b)-gammln(a)-gammln(b)+a*log(x)+b*log(1.0-x));  }
+        
+        if (x < (a+1.0) / (a+b+2.0)) { result = bt*betacf(a,b,x)/a; }
+        else { result = 1.0-bt*betacf(b,a,1.0-x)/b; }
+        
+        return result;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "betai");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+//Numerical Recipes pg. 219
+double LinearAlgebra::gammln(const double xx) {
+    try {
+        int j;
+        double x,y,tmp,ser;
+        static const double cof[6]={76.18009172947146,-86.50532032941677,24.01409824083091,
+            -1.231739572450155,0.120858003e-2,-0.536382e-5};
+        
+        y=x=xx;
+        tmp=x+5.5;
+        tmp -= (x+0.5)*log(tmp);
+        ser=1.0;
+        for (j=0;j<6;j++) {
+            ser += cof[j]/++y;
+        }
+        return -tmp+log(2.5066282746310005*ser/x);
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "gammln");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+//Numerical Recipes pg. 223
+double LinearAlgebra::gammp(const double a, const double x) {
+    try {
+        double gamser,gammcf,gln;
+        
+        if (x < 0.0 || a <= 0.0) { m->mothurOut("[ERROR]: Invalid arguments in routine GAMMP\n"); m->control_pressed = true; return 0.0;}
+        if (x < (a+1.0)) {
+            gser(gamser,a,x,gln);
+            return gamser;
+        } else {
+            gcf(gammcf,a,x,gln);
+            return 1.0-gammcf;
+        }
+        
+        return 0;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "gammp");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+//Numerical Recipes pg. 223
+double LinearAlgebra::gammq(const double a, const double x) {
+    try {
+        double gamser,gammcf,gln;
+        
+        if (x < 0.0 || a <= 0.0) { m->mothurOut("[ERROR]: Invalid arguments in routine GAMMQ\n"); m->control_pressed = true; return 0.0; }
+        if (x < (a+1.0)) {
+            gser(gamser,a,x,gln);
+            return 1.0-gamser;
+        } else {
+            gcf(gammcf,a,x,gln);
+            return gammcf;
+        }   
+        
+        return 0;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "gammp");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+//Numerical Recipes pg. 224
+double LinearAlgebra::gcf(double& gammcf, const double a, const double x, double& gln){
+    try {
+        const int ITMAX=100;
+        const double EPS=numeric_limits<double>::epsilon();
+        const double FPMIN=numeric_limits<double>::min()/EPS;
+        int i;
+        double an,b,c,d,del,h;
+        
+        gln=gammln(a);
+        b=x+1.0-a;
+        c=1.0/FPMIN;
+        d=1.0/b;
+        h=d;
+        for (i=1;i<=ITMAX;i++) {
+            an = -i*(i-a);
+            b += 2.0;
+            d=an*d+b;
+            if (fabs(d) < FPMIN) { d=FPMIN; }
+            c=b+an/c;
+            if (fabs(c) < FPMIN) { c=FPMIN; }
+            d=1.0/d;
+            del=d*c;
+            h *= del;
+            if (fabs(del-1.0) <= EPS) break;
+        }
+        if (i > ITMAX)  { m->mothurOut("[ERROR]: a too large, ITMAX too small in gcf\n"); m->control_pressed = true; }
+        gammcf=exp(-x+a*log(x)-gln)*h;
+        
+        return 0.0;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "gcf");
+               exit(1);
+       }
+
+}
+/*********************************************************************************************************************************/
+//Numerical Recipes pg. 223
+double LinearAlgebra::gser(double& gamser, const double a, const double x, double& gln) {
+    try {
+        int n;
+        double sum,del,ap;
+        const double EPS = numeric_limits<double>::epsilon();
+        
+        gln=gammln(a);
+        if (x <= 0.0) { 
+            if (x < 0.0) {  m->mothurOut("[ERROR]: x less than 0 in routine GSER\n"); m->control_pressed = true;  }
+            gamser=0.0; return 0.0;
+        } else {
+            ap=a;
+            del=sum=1.0/a;
+            for (n=0;n<100;n++) {
+                ++ap;
+                del *= x/ap;
+                sum += del;
+                if (fabs(del) < fabs(sum)*EPS) {
+                    gamser=sum*exp(-x+a*log(x)-gln);
+                    return 0.0;
+                }
+            }
+            
+            m->mothurOut("[ERROR]: a too large, ITMAX too small in routine GSER\n");
+            return 0.0;
+        }
+        return 0;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "gser");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+//Numerical Recipes pg. 233
+double LinearAlgebra::betacf(const double a, const double b, const double x) {
+    try {
+        const int MAXIT = 100;
+        const double EPS = numeric_limits<double>::epsilon();
+        const double FPMIN = numeric_limits<double>::min() / EPS;
+        int m1, m2;
+        double aa, c, d, del, h, qab, qam, qap;
+        
+        qab=a+b;
+        qap=a+1.0;
+        qam=a-1.0;
+        c=1.0;
+        d=1.0-qab*x/qap;
+        if (fabs(d) < FPMIN) d=FPMIN;
+        d=1.0/d;
+        h=d;
+        for (m1=1;m1<=MAXIT;m1++) {
+            m2=2*m1;
+            aa=m1*(b-m1)*x/((qam+m2)*(a+m2));
+            d=1.0+aa*d;
+            if (fabs(d) < FPMIN) d=FPMIN;
+            c=1.0+aa/c;
+            if (fabs(c) < FPMIN) c=FPMIN;
+            d=1.0/d;
+            h *= d*c;
+            aa = -(a+m1)*(qab+m1)*x/((a+m2)*(qap+m2));
+            d=1.0+aa*d;
+            if (fabs(d) < FPMIN) d=FPMIN;
+            c=1.0+aa/c;
+            if (fabs(c) < FPMIN) c=FPMIN;
+            d=1.0/d;
+            del=d*c;
+            h *= del;
+            if (fabs(del-1.0) < EPS) break;
+        }
+        
+        if (m1 > MAXIT) { m->mothurOut("[ERROR]: a or b too big or MAXIT too small in betacf."); m->mothurOutEndLine(); m->control_pressed = true; }
+        return h;
+        
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "betacf");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
 
 vector<vector<double> > LinearAlgebra::matrix_mult(vector<vector<double> > first, vector<vector<double> > second){
        try {
@@ -799,14 +1035,7 @@ double LinearAlgebra::calcKendall(vector<double>& x, vector<double>& y, double&
                                
                double p = (numCoor - numDisCoor) / (float) count;
                
-               //calc signif - zA - http://en.wikipedia.org/wiki/Kendall_tau_rank_correlation_coefficient#Significance_tests
-               double numer = 3.0 * (numCoor - numDisCoor);
-        int n = xscores.size();
-        double denom = n * (n-1) * (2*n + 5) / (double) 2.0;
-        denom = sqrt(denom);
-        sig = numer / denom;
-               
-               if (isnan(sig) || isinf(sig)) { sig = 0.0; }
+               sig = calcKendallSig(x.size(), p);
                
                return p;
        }
@@ -815,12 +1044,434 @@ double LinearAlgebra::calcKendall(vector<double>& x, vector<double>& y, double&
                exit(1);
        }
 }
+double LinearAlgebra::ran0(int& idum)
+{
+    const int IA=16807,IM=2147483647,IQ=127773;
+    const int IR=2836,MASK=123459876;
+    const double AM=1.0/double(IM);
+    int k;
+    double ans;
+    
+    idum ^= MASK;
+    k=idum/IQ;
+    idum=IA*(idum-k*IQ)-IR*k;
+    if (idum < 0) idum += IM;
+    ans=AM*idum;
+    idum ^= MASK;
+    return ans;
+}
+
+double LinearAlgebra::ran1(int &idum)
+{
+       const int IA=16807,IM=2147483647,IQ=127773,IR=2836,NTAB=32;
+       const int NDIV=(1+(IM-1)/NTAB);
+       const double EPS=3.0e-16,AM=1.0/IM,RNMX=(1.0-EPS);
+       static int iy=0;
+       static vector<int> iv(NTAB);
+       int j,k;
+       double temp;
+    
+       if (idum <= 0 || !iy) {
+               if (-idum < 1) idum=1;
+               else idum = -idum;
+               for (j=NTAB+7;j>=0;j--) {
+                       k=idum/IQ;
+                       idum=IA*(idum-k*IQ)-IR*k;
+                       if (idum < 0) idum += IM;
+                       if (j < NTAB) iv[j] = idum;
+               }
+               iy=iv[0];
+       }
+       k=idum/IQ;
+       idum=IA*(idum-k*IQ)-IR*k;
+       if (idum < 0) idum += IM;
+       j=iy/NDIV;
+       iy=iv[j];
+       iv[j] = idum;
+       if ((temp=AM*iy) > RNMX) return RNMX;
+       else return temp;
+}
+
+double LinearAlgebra::ran2(int &idum)
+{
+       const int IM1=2147483563,IM2=2147483399;
+       const int IA1=40014,IA2=40692,IQ1=53668,IQ2=52774;
+       const int IR1=12211,IR2=3791,NTAB=32,IMM1=IM1-1;
+       const int NDIV=1+IMM1/NTAB;
+       const double EPS=3.0e-16,RNMX=1.0-EPS,AM=1.0/double(IM1);
+       static int idum2=123456789,iy=0;
+       static vector<int> iv(NTAB);
+       int j,k;
+       double temp;
+    
+       if (idum <= 0) {
+               idum=(idum==0 ? 1 : -idum);
+               idum2=idum;
+               for (j=NTAB+7;j>=0;j--) {
+                       k=idum/IQ1;
+                       idum=IA1*(idum-k*IQ1)-k*IR1;
+                       if (idum < 0) idum += IM1;
+                       if (j < NTAB) iv[j] = idum;
+               }
+               iy=iv[0];
+       }
+       k=idum/IQ1;
+       idum=IA1*(idum-k*IQ1)-k*IR1;
+       if (idum < 0) idum += IM1;
+       k=idum2/IQ2;
+       idum2=IA2*(idum2-k*IQ2)-k*IR2;
+       if (idum2 < 0) idum2 += IM2;
+       j=iy/NDIV;
+       iy=iv[j]-idum2;
+       iv[j] = idum;
+       if (iy < 1) iy += IMM1;
+       if ((temp=AM*iy) > RNMX) return RNMX;
+       else return temp;
+}
+
+double LinearAlgebra::ran3(int &idum)
+{
+       static int inext,inextp;
+       static int iff=0;
+       const int MBIG=1000000000,MSEED=161803398,MZ=0;
+       const double FAC=(1.0/MBIG);
+       static vector<int> ma(56);
+       int i,ii,k,mj,mk;
+    
+       if (idum < 0 || iff == 0) {
+               iff=1;
+               mj=labs(MSEED-labs(idum));
+               mj %= MBIG;
+               ma[55]=mj;
+               mk=1;
+               for (i=1;i<=54;i++) {
+                       ii=(21*i) % 55;
+                       ma[ii]=mk;
+                       mk=mj-mk;
+                       if (mk < int(MZ)) mk += MBIG;
+                       mj=ma[ii];
+               }
+               for (k=0;k<4;k++)
+                       for (i=1;i<=55;i++) {
+                               ma[i] -= ma[1+(i+30) % 55];
+                               if (ma[i] < int(MZ)) ma[i] += MBIG;
+                       }
+               inext=0;
+               inextp=31;
+               idum=1;
+       }
+       if (++inext == 56) inext=1;
+       if (++inextp == 56) inextp=1;
+       mj=ma[inext]-ma[inextp];
+       if (mj < int(MZ)) mj += MBIG;
+       ma[inext]=mj;
+       return mj*FAC;
+}
+
+double LinearAlgebra::ran4(int &idum)
+{
+#if defined(vax) || defined(_vax_) || defined(__vax__) || defined(VAX)
+       static const unsigned long jflone = 0x00004080;
+       static const unsigned long jflmsk = 0xffff007f;
+#else
+       static const unsigned long jflone = 0x3f800000;
+       static const unsigned long jflmsk = 0x007fffff;
+#endif
+       unsigned long irword,itemp,lword;
+       static int idums = 0;
+    
+       if (idum < 0) {
+               idums = -idum;
+               idum=1;
+       }
+       irword=idum;
+       lword=idums;
+       psdes(lword,irword);
+       itemp=jflone | (jflmsk & irword);
+       ++idum;
+       return (*(float *)&itemp)-1.0;
+}
+
+void LinearAlgebra::psdes(unsigned long &lword, unsigned long &irword)
+{
+       const int NITER=4;
+       static const unsigned long c1[NITER]={
+               0xbaa96887L, 0x1e17d32cL, 0x03bcdc3cL, 0x0f33d1b2L};
+       static const unsigned long c2[NITER]={
+               0x4b0f3b58L, 0xe874f0c3L, 0x6955c5a6L, 0x55a7ca46L};
+       unsigned long i,ia,ib,iswap,itmph=0,itmpl=0;
+    
+       for (i=0;i<NITER;i++) {
+               ia=(iswap=irword) ^ c1[i];
+               itmpl = ia & 0xffff;
+               itmph = ia >> 16;
+               ib=itmpl*itmpl+ ~(itmph*itmph);
+               irword=lword ^ (((ia = (ib >> 16) |
+                          ((ib & 0xffff) << 16)) ^ c2[i])+itmpl*itmph);
+               lword=iswap;
+       }
+}
+/*********************************************************************************************************************************/
+double LinearAlgebra::calcKendallSig(double n, double r){
+    try {
+        
+        double sig = 0.0;
+        double svar=(4.0*n+10.0)/(9.0*n*(n-1.0)); 
+        double z= r/sqrt(svar); 
+        sig=erfcc(fabs(z)/1.4142136);
+
+               if (isnan(sig) || isinf(sig)) { sig = 0.0; }
+        
+        return sig;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "calcKendallSig");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+double LinearAlgebra::calcKruskalWallis(vector<spearmanRank>& values, double& pValue){
+       try {
+        double H;
+        set<string> treatments;
+        
+        //rank values
+        sort(values.begin(), values.end(), compareSpearman);
+        vector<spearmanRank*> ties;
+        int rankTotal = 0;
+        vector<int> TIES;
+        for (int j = 0; j < values.size(); j++) {
+            treatments.insert(values[j].name);
+            rankTotal += (j+1);
+            ties.push_back(&(values[j]));
+            
+            if (j != values.size()-1) { // you are not the last so you can look ahead
+                if (values[j].score != values[j+1].score) { // you are done with ties, rank them and continue
+                    if (ties.size() > 1) { TIES.push_back(ties.size()); }
+                    for (int k = 0; k < ties.size(); k++) {
+                        double thisrank = rankTotal / (double) ties.size();
+                        (*ties[k]).score = thisrank;
+                    }
+                    ties.clear();
+                    rankTotal = 0;
+                }
+            }else { // you are the last one
+                if (ties.size() > 1) { TIES.push_back(ties.size()); }
+                for (int k = 0; k < ties.size(); k++) {
+                    double thisrank = rankTotal / (double) ties.size();
+                    (*ties[k]).score = thisrank;
+                }
+            }
+        }
+        
+        
+        // H = 12/(N*(N+1)) * (sum Ti^2/n) - 3(N+1)
+        map<string, double> sums;
+        map<string, double> counts;
+        for (set<string>::iterator it = treatments.begin(); it != treatments.end(); it++) { sums[*it] = 0.0; counts[*it] = 0; }
+        
+        for (int j = 0; j < values.size(); j++) {
+            sums[values[j].name] += values[j].score;
+            counts[values[j].name]+= 1.0;
+        }
+        
+        double middleTerm = 0.0;
+        for (set<string>::iterator it = treatments.begin(); it != treatments.end(); it++) {
+            middleTerm += ((sums[*it]*sums[*it])/counts[*it]);
+        }
+        
+        double firstTerm = 12 / (double) (values.size()*(values.size()+1));
+        double lastTerm = 3 * (values.size()+1);
+        
+        H = firstTerm * middleTerm - lastTerm;
+        
+        //adjust for ties
+        if (TIES.size() != 0) {
+            double sum = 0.0;
+            for (int j = 0; j < TIES.size(); j++) { sum += ((TIES[j]*TIES[j]*TIES[j])-TIES[j]); }
+            double result = 1.0 - (sum / (double) ((values.size()*values.size()*values.size())-values.size()));
+            H /= result;
+        }
+        
+        //Numerical Recipes pg221
+        pValue = 1.0 - (gammp(((treatments.size()-1)/(double)2.0), H/2.0));
+        
+        return H;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "calcKruskalWallis");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+//thanks http://www.johndcook.com/cpp_phi.html
+double LinearAlgebra::pnorm(double x){
+    try {
+        // constants
+        double a1 =  0.254829592;
+        double a2 = -0.284496736;
+        double a3 =  1.421413741;
+        double a4 = -1.453152027;
+        double a5 =  1.061405429;
+        double p  =  0.3275911;
+        
+        // Save the sign of x
+        int sign = 1;
+        if (x < 0)
+            sign = -1;
+        x = fabs(x)/sqrt(2.0);
+        
+        // A&S formula 7.1.26
+        double t = 1.0/(1.0 + p*x);
+        double y = 1.0 - (((((a5*t + a4)*t) + a3)*t + a2)*t + a1)*t*exp(-x*x);
+        
+        return 0.5*(1.0 + sign*y);
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "pnorm");
+               exit(1);
+       }
+}
+
+/*********************************************************************************************************************************/
+double LinearAlgebra::calcWilcoxon(vector<double>& x, vector<double>& y, double& sig){
+       try {           
+               double W = 0.0;
+        sig = 0.0;
+        
+        vector<spearmanRank> ranks;
+        for (int i = 0; i < x.size(); i++) {
+            if (m->control_pressed) { return W; }
+            spearmanRank member("x", x[i]);
+            ranks.push_back(member);
+        }
+        
+        for (int i = 0; i < y.size(); i++) {
+            if (m->control_pressed) { return W; }
+            spearmanRank member("y", y[i]);
+            ranks.push_back(member);
+        }
+        
+        //sort values
+               sort(ranks.begin(), ranks.end(), compareSpearman);
+               
+               //convert scores to ranks of x
+               vector<spearmanRank*> ties;
+               int rankTotal = 0;
+        vector<int> TIES;
+               for (int j = 0; j < ranks.size(); j++) {
+            if (m->control_pressed) { return W; }
+                       rankTotal += (j+1);
+                       ties.push_back(&(ranks[j]));
+            
+                       if (j != ranks.size()-1) { // you are not the last so you can look ahead
+                               if (ranks[j].score != ranks[j+1].score) { // you are done with ties, rank them and continue
+                    if (ties.size() > 1) { TIES.push_back(ties.size()); }
+                                       for (int k = 0; k < ties.size(); k++) {
+                                               float thisrank = rankTotal / (float) ties.size();
+                                               (*ties[k]).score = thisrank;
+                                       }
+                                       ties.clear();
+                                       rankTotal = 0;
+                               }
+                       }else { // you are the last one
+                if (ties.size() > 1) { TIES.push_back(ties.size()); }
+                               for (int k = 0; k < ties.size(); k++) {
+                                       float thisrank = rankTotal / (float) ties.size();
+                                       (*ties[k]).score = thisrank;
+                               }
+                       }
+               }
+        
+        //from R wilcox.test function
+        //STATISTIC <- sum(r[seq_along(x)]) - n.x * (n.x + 1)/2
+        double sumRanks = 0.0;
+        for (int i = 0; i < ranks.size(); i++) {
+            if (m->control_pressed) { return W; }
+            if (ranks[i].name == "x") { sumRanks += ranks[i].score; }
+        }
+        
+        W = sumRanks - x.size() * ((double)(x.size() + 1)) / 2.0;
+        
+        //exact <- (n.x < 50) && (n.y < 50)
+        bool findExact = false;
+        if ((x.size() < 50) && (y.size() < 50)) { findExact = true; }
+        
+        
+        if (findExact && (TIES.size() == 0)) { //find exact and no ties
+            //PVAL <- switch(alternative, two.sided = {
+            //p <- if (STATISTIC > (n.x * n.y/2))
+            PWilcox wilcox;
+            double pval = 0.0;
+            if (W > ((double)x.size()*y.size()/2.0)) {
+                //pwilcox(STATISTIC-1, n.x, n.y, lower.tail = FALSE)
+                pval = wilcox.pwilcox(W-1, x.size(), y.size(), false);
+            }else {
+                //pwilcox(STATISTIC,n.x, n.y)
+                pval = wilcox.pwilcox(W, x.size(), y.size(), true);
+            }
+            sig = 2.0 * pval;
+            if (1.0 < sig) { sig = 1.0; }
+        }else {
+            //z <- STATISTIC - n.x * n.y/2
+            double z = W - (double)(x.size() * y.size()/2.0);
+            //NTIES <- table(r)
+            double sum = 0.0;
+            for (int j = 0; j < TIES.size(); j++) { sum += ((TIES[j]*TIES[j]*TIES[j])-TIES[j]); }
+           
+            //SIGMA <- sqrt((n.x * n.y/12) * ((n.x + n.y + 1) -
+                                            //sum(NTIES^3 - NTIES)/((n.x + n.y) * (n.x + n.y -
+                                                                            //1))))
+            double sigma = 0.0;
+            double firstTerm = (double)(x.size() * y.size()/12.0);
+            double secondTerm = (double)(x.size() + y.size() + 1) - sum / (double)((x.size() + y.size()) * (x.size() + y.size() - 1));
+            sigma = sqrt(firstTerm * secondTerm);
+            
+            //CORRECTION <- switch(alternative, two.sided = sign(z) * 0.5, greater = 0.5, less = -0.5)
+            double CORRECTION = 0.0;
+            if (z < 0) { CORRECTION = -1.0; }
+            else if (z > 0) { CORRECTION = 1.0; }
+            CORRECTION *= 0.5;
+            
+            z = (z - CORRECTION)/sigma;
+            
+            //PVAL <- switch(alternative,  two.sided = 2 * min(pnorm(z), pnorm(z, lower.tail = FALSE)))
+            sig = pnorm(z);
+            if ((1.0-sig) < sig) { sig = 1.0 - sig; }
+            sig *= 2;
+        }
+        
+        return W;
+       }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "calcWilcoxon");
+               exit(1);
+       }
+}
+
+/*********************************************************************************************************************************/
+double LinearAlgebra::choose(double n, double k){
+       try {
+        n = floor(n + 0.5);
+        k = floor(k + 0.5);
+        
+        double lchoose = gammln(n + 1.0) - gammln(k + 1.0) - gammln(n - k + 1.0);
+        
+        return (floor(exp(lchoose) + 0.5));
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "choose");
+               exit(1);
+       }
+}
 /*********************************************************************************************************************************/
 double LinearAlgebra::calcSpearman(vector<double>& x, vector<double>& y, double& sig){
        try {
                if (x.size() != y.size()) { m->mothurOut("[ERROR]: vector size mismatch."); m->mothurOutEndLine(); return 0.0; }
                
                //format data
+        double sf = 0.0; //f^3 - f where f is the number of ties in x;
+        double sg = 0.0; //f^3 - f where f is the number of ties in y;
                map<float, int> tableX; 
                map<float, int>::iterator itTable;
                vector<spearmanRank> xscores; 
@@ -865,6 +1516,8 @@ double LinearAlgebra::calcSpearman(vector<double>& x, vector<double>& y, double&
                                                float thisrank = rankTotal / (float) xties.size();
                                                rankx[xties[k].name] = thisrank;
                                        }
+                    int t = xties.size();
+                    sf += (t*t*t-t);
                                        xties.clear();
                                        rankTotal = 0;
                                }
@@ -915,6 +1568,8 @@ double LinearAlgebra::calcSpearman(vector<double>& x, vector<double>& y, double&
                                                float thisrank = rankTotal / (float) yties.size();
                                                rank[yties[k].name] = thisrank;
                                        }
+                    int t = yties.size();
+                    sg += (t*t*t-t);
                                        yties.clear();
                                        rankTotal = 0;
                                }
@@ -943,19 +1598,52 @@ double LinearAlgebra::calcSpearman(vector<double>& x, vector<double>& y, double&
                                
                p = (SX2 + SY2 - di) / (2.0 * sqrt((SX2*SY2)));
                
-               //signifigance calc - http://en.wikipedia.org/wiki/Spearman%27s_rank_correlation_coefficient
-               double temp = (x.size()-2) / (double) (1- (p*p));
-               temp = sqrt(temp);
-               sig = p*temp;
-               if (isnan(sig) || isinf(sig)) { sig = 0.0; }
-                               
+               //Numerical Recipes 646
+        sig = calcSpearmanSig(n, sf, sg, di);
+               
                return p;
        }
        catch(exception& e) {
                m->errorOut(e, "LinearAlgebra", "calcSpearman");
                exit(1);
        }
-}              
+}
+/*********************************************************************************************************************************/
+double LinearAlgebra::calcSpearmanSig(double n, double sf, double sg, double d){
+    try {
+        
+        double sig = 0.0;
+        double probrs = 0.0;
+        double en=n;
+        double en3n=en*en*en-en;
+        double aved=en3n/6.0-(sf+sg)/12.0;
+        double fac=(1.0-sf/en3n)*(1.0-sg/en3n);
+        double vard=((en-1.0)*en*en*SQR(en+1.0)/36.0)*fac;
+        double zd=(d-aved)/sqrt(vard);
+        double probd=erfcc(fabs(zd)/1.4142136);
+        double rs=(1.0-(6.0/en3n)*(d+(sf+sg)/12.0))/sqrt(fac);
+        fac=(rs+1.0)*(1.0-rs);
+        if (fac > 0.0) {
+            double t=rs*sqrt((en-2.0)/fac);
+            double df=en-2.0;
+            probrs=betai(0.5*df,0.5,df/(df+t*t));
+        }else {
+            probrs = 0.0;
+        }
+        
+        //smaller of probd and probrs is sig
+        sig = probrs;
+        if (probd < probrs) { sig = probd; }
+        
+               if (isnan(sig) || isinf(sig)) { sig = 0.0; }
+               
+        return sig;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "calcSpearmanSig");
+               exit(1);
+       }
+}
 /*********************************************************************************************************************************/
 double LinearAlgebra::calcPearson(vector<double>& x, vector<double>& y, double& sig){
        try {
@@ -989,11 +1677,8 @@ double LinearAlgebra::calcPearson(vector<double>& x, vector<double>& y, double&
                                
                r = numerator / denom;
                
-               //signifigance calc - http://faculty.vassar.edu/lowry/ch4apx.html
-               double temp =  (1- (r*r)) / (double) (x.size()-2);
-               temp = sqrt(temp);
-               sig = r / temp;
-               if (isnan(sig) || isinf(sig)) { sig = 0.0; }
+               //Numerical Recipes pg.644
+        sig = calcPearsonSig(x.size(), r);
                
                return r;
        }
@@ -1001,33 +1686,331 @@ double LinearAlgebra::calcPearson(vector<double>& x, vector<double>& y, double&
                m->errorOut(e, "LinearAlgebra", "calcPearson");
                exit(1);
        }
-}                      
+}
+/*********************************************************************************************************************************/
+double LinearAlgebra::calcPearsonSig(double n, double r){
+    try {
+        
+        double sig = 0.0;
+        const double TINY = 1.0e-20;
+        double z = 0.5*log((1.0+r+TINY)/(1.0-r+TINY)); //Fisher's z transformation
+    
+        //code below was giving an error in betacf with sop files
+        //int df = n-2;
+        //double t = r*sqrt(df/((1.0-r+TINY)*(1.0+r+TINY)));
+        //sig = betai(0.5+df, 0.5, df/(df+t*t));
+        
+        //Numerical Recipes says code below gives approximately the same result
+        sig = erfcc(fabs(z*sqrt(n-1.0))/1.4142136);
+               if (isnan(sig) || isinf(sig)) { sig = 0.0; }
+               
+        return sig;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "calcPearsonSig");
+               exit(1);
+       }
+}
 /*********************************************************************************************************************************/
 
 vector<vector<double> > LinearAlgebra::getObservedEuclideanDistance(vector<vector<double> >& relAbundData){
+    try {
 
-       int numSamples = relAbundData.size();
-       int numOTUs = relAbundData[0].size();
-       
-       vector<vector<double> > dMatrix(numSamples);
-       for(int i=0;i<numSamples;i++){
-               dMatrix[i].resize(numSamples);
+        int numSamples = relAbundData.size();
+        int numOTUs = relAbundData[0].size();
+        
+        vector<vector<double> > dMatrix(numSamples);
+        for(int i=0;i<numSamples;i++){
+            dMatrix[i].resize(numSamples);
+        }
+        
+        for(int i=0;i<numSamples;i++){
+            for(int j=0;j<numSamples;j++){
+                
+                if (m->control_pressed) { return dMatrix; }
+                
+                double d = 0;
+                for(int k=0;k<numOTUs;k++){
+                    d += pow((relAbundData[i][k] - relAbundData[j][k]), 2.0000);
+                }
+                dMatrix[i][j] = pow(d, 0.50000);
+                dMatrix[j][i] = dMatrix[i][j];
+                
+            }
+        }
+        return dMatrix;
        }
-       
-       for(int i=0;i<numSamples;i++){
-               for(int j=0;j<numSamples;j++){
-                       
-                       double d = 0;
-                       for(int k=0;k<numOTUs;k++){
-                               d += pow((relAbundData[i][k] - relAbundData[j][k]), 2.0000);
-                       }
-                       dMatrix[i][j] = pow(d, 0.50000);
-                       dMatrix[j][i] = dMatrix[i][j];
-                       
-               }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "getObservedEuclideanDistance");
+               exit(1);
        }
-       return dMatrix;
-       
 }
 
 /*********************************************************************************************************************************/
+vector<double> LinearAlgebra::solveEquations(vector<vector<double> > A, vector<double> b){
+    try {
+        int length = (int)b.size();
+        vector<double> x(length, 0);
+        vector<int> index(length);
+        for(int i=0;i<length;i++){  index[i] = i;   }
+        double d;
+        
+        ludcmp(A, index, d);  if (m->control_pressed) { return b; }
+        lubksb(A, index, b);
+        
+        return b;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "solveEquations");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+vector<float> LinearAlgebra::solveEquations(vector<vector<float> > A, vector<float> b){
+    try {
+        int length = (int)b.size();
+        vector<double> x(length, 0);
+        vector<int> index(length);
+        for(int i=0;i<length;i++){  index[i] = i;   }
+        float d;
+        
+        ludcmp(A, index, d);  if (m->control_pressed) { return b; }
+        lubksb(A, index, b);
+        
+        return b;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "solveEquations");
+               exit(1);
+       }
+}
+
+/*********************************************************************************************************************************/
+
+void LinearAlgebra::ludcmp(vector<vector<double> >& A, vector<int>& index, double& d){
+    try {
+        double tiny = 1e-20;
+        
+        int n = (int)A.size();
+        vector<double> vv(n, 0.0);
+        double temp;
+        int imax;
+        
+        d = 1.0;
+        
+        for(int i=0;i<n;i++){
+            double big = 0.0;
+            for(int j=0;j<n;j++){   if((temp=fabs(A[i][j])) > big ) big=temp;  }
+            if(big==0.0){   m->mothurOut("Singular matrix in routine ludcmp\n");    }
+            vv[i] = 1.0/big;
+        }
+        
+        for(int j=0;j<n;j++){
+            if (m->control_pressed) { break; }
+            for(int i=0;i<j;i++){
+                double sum = A[i][j];
+                for(int k=0;k<i;k++){   sum -= A[i][k] * A[k][j];   }
+                A[i][j] = sum;
+            }
+            
+            double big = 0.0;
+            for(int i=j;i<n;i++){
+                double sum = A[i][j];
+                for(int k=0;k<j;k++){   sum -= A[i][k] * A[k][j];   }
+                A[i][j] = sum;
+                double dum;
+                if((dum = vv[i] * fabs(sum)) >= big){
+                    big = dum;
+                    imax = i;
+                }
+            }
+            if(j != imax){
+                for(int k=0;k<n;k++){
+                    double dum = A[imax][k];
+                    A[imax][k] = A[j][k];
+                    A[j][k] = dum;
+                }
+                d = -d;
+                vv[imax] = vv[j];
+            }
+            index[j] = imax;
+            
+            if(A[j][j] == 0.0){ A[j][j] = tiny; }
+            
+            if(j != n-1){
+                double dum = 1.0/A[j][j];
+                for(int i=j+1;i<n;i++){ A[i][j] *= dum; }
+            }
+        }
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "ludcmp");
+               exit(1);
+       }
+}
+
+/*********************************************************************************************************************************/
+
+void LinearAlgebra::lubksb(vector<vector<double> >& A, vector<int>& index, vector<double>& b){
+    try {
+        double total;
+        int n = (int)A.size();
+        int ii = 0;
+        
+        for(int i=0;i<n;i++){
+            if (m->control_pressed) { break; }
+            int ip = index[i];
+            total = b[ip];
+            b[ip] = b[i];
+            
+            if (ii != 0) {
+                for(int j=ii-1;j<i;j++){
+                    total -= A[i][j] * b[j];
+                }
+            }
+            else if(total != 0){  ii = i+1;   }
+            b[i] = total;
+        }
+        for(int i=n-1;i>=0;i--){
+            total = b[i];
+            for(int j=i+1;j<n;j++){ total -= A[i][j] * b[j];  }
+            b[i] = total / A[i][i];
+        }
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "lubksb");
+               exit(1);
+       }
+}
+/*********************************************************************************************************************************/
+
+void LinearAlgebra::ludcmp(vector<vector<float> >& A, vector<int>& index, float& d){
+    try {
+        double tiny = 1e-20;
+        
+        int n = (int)A.size();
+        vector<float> vv(n, 0.0);
+        double temp;
+        int imax;
+        
+        d = 1.0;
+        
+        for(int i=0;i<n;i++){
+            float big = 0.0;
+            for(int j=0;j<n;j++){   if((temp=fabs(A[i][j])) > big ) big=temp;  }
+            if(big==0.0){   m->mothurOut("Singular matrix in routine ludcmp\n");    }
+            vv[i] = 1.0/big;
+        }
+        
+        for(int j=0;j<n;j++){
+            if (m->control_pressed) { break; }
+            for(int i=0;i<j;i++){
+                float sum = A[i][j];
+                for(int k=0;k<i;k++){   sum -= A[i][k] * A[k][j];   }
+                A[i][j] = sum;
+            }
+            
+            float big = 0.0;
+            for(int i=j;i<n;i++){
+                float sum = A[i][j];
+                for(int k=0;k<j;k++){   sum -= A[i][k] * A[k][j];   }
+                A[i][j] = sum;
+                float dum;
+                if((dum = vv[i] * fabs(sum)) >= big){
+                    big = dum;
+                    imax = i;
+                }
+            }
+            if(j != imax){
+                for(int k=0;k<n;k++){
+                    float dum = A[imax][k];
+                    A[imax][k] = A[j][k];
+                    A[j][k] = dum;
+                }
+                d = -d;
+                vv[imax] = vv[j];
+            }
+            index[j] = imax;
+            
+            if(A[j][j] == 0.0){ A[j][j] = tiny; }
+            
+            if(j != n-1){
+                float dum = 1.0/A[j][j];
+                for(int i=j+1;i<n;i++){ A[i][j] *= dum; }
+            }
+        }
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "ludcmp");
+               exit(1);
+       }
+}
+
+/*********************************************************************************************************************************/
+
+void LinearAlgebra::lubksb(vector<vector<float> >& A, vector<int>& index, vector<float>& b){
+    try {
+        float total;
+        int n = (int)A.size();
+        int ii = 0;
+        
+        for(int i=0;i<n;i++){
+            if (m->control_pressed) { break; }
+            int ip = index[i];
+            total = b[ip];
+            b[ip] = b[i];
+            
+            if (ii != 0) {
+                for(int j=ii-1;j<i;j++){
+                    total -= A[i][j] * b[j];
+                }
+            }
+            else if(total != 0){  ii = i+1;   }
+            b[i] = total;
+        }
+        for(int i=n-1;i>=0;i--){
+            total = b[i];
+            for(int j=i+1;j<n;j++){ total -= A[i][j] * b[j];  }
+            b[i] = total / A[i][i];
+        }
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "lubksb");
+               exit(1);
+       }
+}
+
+/*********************************************************************************************************************************/
+
+vector<vector<double> > LinearAlgebra::getInverse(vector<vector<double> > matrix){
+    try {
+        int n = (int)matrix.size();
+        
+        vector<vector<double> > inverse(n);
+        for(int i=0;i<n;i++){   inverse[i].assign(n, 0.0000);   }
+        
+        vector<double> column(n, 0.0000);
+        vector<int> index(n, 0);
+        double dummy;
+        
+        ludcmp(matrix, index, dummy);
+        
+        for(int j=0;j<n;j++){
+            if (m->control_pressed) { break; }
+            
+            column.assign(n, 0);
+            
+            column[j] = 1.0000;
+            
+            lubksb(matrix, index, column);
+            
+            for(int i=0;i<n;i++){   inverse[i][j] = column[i];  }
+        }
+        
+        return inverse;
+    }
+       catch(exception& e) {
+               m->errorOut(e, "LinearAlgebra", "getInverse");
+               exit(1);
+       }
+}