Question

我正在尝试使用R中的Diffeqr包（文档的link）来解决ODE系统。解决系统错误时，指出：“ 需要更大的maxiters 。”

示例：

library(diffeqr)
library(plotly)

diffeq_setup()

### Adapted Zombie apocalypse model (Munz, 2009) ###

# Drift function
f <- function(u,p,t) {
  du1 = u[4] * u[1] - p[1] * u[1] * u[3] + p[2] * u[2]
  du2 = p[1] * u[1] * u[3] - p[2] * u[2] - p[3] * u[2]
  du3 = 100 + p[3] * u[2] - p[1] * u[1] * u[3] + p[2] * u[2]
  du4 = 0
  return(c(du1,du2, du3, du4))
}

# Diffusion function (note that noise terms are 0)
g <- function(u,p,t) {
  return(c(0*u[1], 0*u[2], 0*u[3], 0*u[4]))
}

u0 = c(100000, 0, 0, 0.7)            # initial conditions
tspan <- list(0.0,1000)              # timespan to solve over
p = c(0.0002, 0.005, 0.02)           # parameter values
sol = diffeqr::sde.solve(f,g,u0,tspan,p=p,saveat=1, abstol = 10^(-3))
udf = as.data.frame(sol$u)

plot_ly(udf, x = sol$t, y = ~V1, name = 'Zombies', type = 'scatter', mode = 'lines') %>%
  add_trace(y = ~V2, name = 'Zombie/human conflicts', mode = 'lines') %>%
  add_trace(y = ~V3, name = 'Zombies', mode = 'lines')

发生的错误如下：

> sol = diffeqr::sde.solve(f,g,u0,tspan,p=p,saveat=1, abstol = 10^(-3))
┌ Warning: Interrupted. Larger maxiters is needed.
└ @ DiffEqBase ~/.julia/packages/DiffEqBase/cp0Wf/src/integrator_interface.jl:150

我尝试在maxiter中指定sde.solve()，但是无法在其中添加maxiter参数。

问题您如何手动将maxiter设置为更高的值？

在Diffeqr软件包中指定maxiter

0 个答案: