# This is a code for 8.08 - 8.S308 recitation
# KPZ stochastic pde integration

# for installing required packages
# using Pkg
# Pkg.add("Plots")
# Pkg.add("Random")
# Pkg.add("LsqFit")
# Pkg.add("ProgressBars")
# Pkg.add("FFTW")

# for plotting
using Plots
using Random
using LsqFit
using ProgressBars
using FFTW


cd(@__DIR__)
include("Rec10_KPZ_module.jl")

#random number generator
rng = MersenneTwister(1234)

# parameters
L = 128     # system length
lam = 3     # strength of nonlinearity
nu = 1      # diffusivity
D = 1       # noise strength
dt = 0.02   # spacing between time points
# using dx = 1 WLOG

# set parameters
param = Rec.setParam(L,lam,nu,D,dt)

# set state
state = Rec.setState(param)

# create movie of positions
t_gap = 2     # gap between frames
n_frame = 100 # number of frames
fps = 10      # fps of gif
get_movie!(state, param, rng, t_gap, n_frame, fps)

# estimate exponents
n_seeds = 20
n_pts = 40
Ls = [50,71,100,141,200,283,400]#,566,1778]
ts_Lmin = 10 .^ range(0, 3, length=n_pts)
ts = [ts_Lmin .* (Ls[i] / Ls[1])^1.5 for i in eachindex(Ls)]

get_exponents(lam, nu, D, dt, Ls, ts, rng, n_seeds)