The function computes regression coefficients for a fused lasso penalized regression model for a given pair of lambda1 and lambda2 values.
fl.lambda(n,p,x,y,xpx,dxpx,xpy,beta.old,ofv.old,alpha,
lambda1,lambda2,tol,maxiter,eps,xbeta.old)
Number of observations
Number of predictors.
A n by l matrix of predictors. Here n is number of observations, l is number of active variables.
a vector of n observations.
The X'X matrix
A vector of order l of diagonal elements of x'x
A vector of order l containing x'y
A vector initial values of beta. Optional
Objective function value at beta.old
Approximation to be used for absolute value. Default is 10^-6.
The value of lambda1
The value of lambda2
Tolerance criterion. Default is 10^-7
Maximum number of iterations. Default is 100000.
Value for which beta is set to zero if -eps<beta<eps. Default is 10^-6
A n by 1 vector of xbeta values. Optional
A list with following components
Coefficient estimates
"yes" means converged and "no" means did not converge
Number of iterations to estimate the coefficients
Objective function value at solution
This function is internal and used by fusedlasso function. User need not call this function.