fzero function from MATLAB to R - r

Question

I want to use R's fzero function to find roots of a function. The problem gets complicated, as the function in question calls some other functions which in turn call another ones. I do have MATLAB code that does it and I am trying to translate it to R, but cannot make in work. My experience with MATLAB is limited, so it's probable I just missed some feature of the MATLAB code while translating. My ultimate goal is to obtain R's working equivalent of the MATLAB code. Any hints will by highly appreciated!
The error I got is in function psi():
Error in (-t(I) * pi^2) %*% time : non-conformable arguments
Although the sizes of matrices do match and this part of code works with some naive input when ran in isolation.
NB: I have tried using mrdivide (R's equivalent of MATLAB's right matrix division) in some places, but with no effect.
NB2: I obtain the same error trying function uniroot instead of fzero.
# Global parameters:
N = 140
A2 = (256 times 256) matrix with data
I = vector of size 256: (0, 1, 2^2, 3^2, 4^2, ..., 255^2)
# ----------------------------------------------------------------
MATLAB working code:
fzero( #(t)(t-evolve(t)),[0,0.1])
function [out,time]=evolve(t)
global N
Sum_func = func([0,2],t) + func([2,0],t) + 2*func([1,1],t);
time=(2*pi*N*Sum_func)^(-1/3);
out=(t-time)/time;
end
function out=func(s,t)
global N
if sum(s)<=4
Sum_func=func([s(1)+1,s(2)],t)+func([s(1),s(2)+1],t); const=
(1+1/2^(sum(s)+1))/3;
time=(-2*const*K(s(1))*K(s(2))/N/Sum_func)^(1/(2+sum(s)));
out=psi(s,time);
else
out=psi(s,t);
end
end
function out=psi(s,Time)
global I A2
% s is a vector
w=exp(-I*pi^2*Time).*[1,.5*ones(1,length(I)-1)];
wx=w.*(I.^s(1));
wy=w.*(I.^s(2));
out=(-1)^sum(s)*(wy*A2*wx')*pi^(2*sum(s));
end
function out=K(s)
out=(-1)^s*prod((1:2:2*s-1))/sqrt(2*pi);
end
# ----------------------------------------------------------------
My attempt at R translation (not working):
fzero(subtract_evolve, c(0, 0.1))
K <- function(s) {
out <- (-1)^s * prod(seq(from = 1,to = 2*s-1, by = 2))/sqrt(2*pi)
return(out)
}
psi <- function(s, time) {
w <- (exp((-t(I) * pi^2) %*% time)) *
t(c(cbind(1, 0.5*ones(1,length(I)-1))))
wx <- t(w * (I^s[1]))
wy <- t(w * (I^s[2]))
out <- (-1)^sum(s) * (wy %*% A2 %*% t(wx)) * pi^(2*sum(s))
return(out)
}
func <- function(s, t) {
if (sum(s) <= 4) {
sum_func <- func(c(s[1]+1,s[2]), t) + func(c(s[1],s[2]+1), t)
const <- (1+1/2^(sum(s)+1))/3
time <- (-2 * const * K(s[1]) * K(s[2]) / N / sum_func)^(1/(2+sum(s)))
out <- psi(s, time)
} else {
out <- psi(s, t)
}
return(out)
}
evolve <- function(t) {
sum_func = func(c(0,2), t) + func(c(2,0), t) + 2*func(c(1,1),t)
time <- (2*pi*N*Sum_func)^(-1/3)
out <- (t-time)/time
return(c(out, time))
}
subtract_evolve <- function(t) {
return(t - evolve(t))
}