我对何时使用ode45（@ functionname，tspan，initialvalues，...）或ode45（'functionname'，tspan，initial values，...）感到有些困惑。我见过使用这两种情况的例子，但有时一种是有效的，另一种则没有。
e.g。
[HttpGet]
public ActionResult BookFlight()
{
// Check if the user is logged in, if not redirect to log in page
if (User.Identity.IsAuthenticated)
{
SetDepartureandArrival();
return View();
}
else
return RedirectToAction("../User/LogIn");
}
public void SetDepartureandArrival()
{
Departures.Add(new SelectListItem { Text = "-Select-", Value = "0" });
Departures.Add(new SelectListItem { Text = "London", Value = "London" });
Departures.Add(new SelectListItem { Text = "Manchester", Value = "Manchester" });
Departures.Add(new SelectListItem { Text = "Edinburgh", Value = "Edinburgh" });
Departures.Add(new SelectListItem { Text = "East Midlands", Value = "East Midlands" });
Departures.Add(new SelectListItem { Text = "Bristol", Value = "Bristol" });
ViewData["departures"] = Departures;
Arrivals.Add(new SelectListItem { Text = "-Select- ", Value = "0" });
Arrivals.Add(new SelectListItem { Text = "Paris", Value = "Paris" });
Arrivals.Add(new SelectListItem { Text = "Barcelona", Value = "Barcelona" });
Arrivals.Add(new SelectListItem { Text = "Madrid", Value = "Madrid" });
Arrivals.Add(new SelectListItem { Text = "Amsterdam", Value = "Amsterdam" });
Arrivals.Add(new SelectListItem { Text = "Prague", Value = "Prague" });
Arrivals.Add(new SelectListItem { Text = "Nice", Value = "Nice" });
Arrivals.Add(new SelectListItem { Text = "Milan", Value = "Milan" });
Arrivals.Add(new SelectListItem { Text = "Geneva", Value = "Geneva" });
Arrivals.Add(new SelectListItem { Text = "Rome", Value = "Rome" });
ViewData["arrivals"] = Arrivals;
}
[HttpPost]
public ActionResult BookFlight(FlightDetailsMD flights, FormCollection form)
{
Random rand = new Random();
Random rand2 = new Random();
if (ModelState.IsValid)
{
var departureVal = form["departures"];
var arrivalVal = form["arrivals"];
using (var db = new FlightDetailsEntities())
{
var user = db.FlightDetails.Create();
user.Id = rand.Next(100000, 199999) + rand2.Next(100000, 199999);
user.Departure = departureVal;
user.Arrivals = arrivalVal;
user.DepartureDate = flights.DepartureDate;
user.ReturnDate = flights.ReturnDate;
db.FlightDetails.Add(user);
db.SaveChanges();
MailMessage mail = new MailMessage();
mail.To.Add(User.Identity.Name);
mail.From = new MailAddress(User.Identity.Name);
mail.Subject = "Booking Confirmation";
string Body = "Email from: <i>insert company name</i><br><br> Your booking is confirmed! You are going to " + user.Arrivals +
" on " + string.Format("{0:dd/MM/yyyy}", user.DepartureDate) + " and returning to " + user.Departure + " on " + string.Format("{0:dd/MM/yyyy}", user.ReturnDate) +
".<br> Thank you for booking with us and we hope you have a nice time!" + "<br><h2>Reference #" + user.Id + "</h2>";
mail.Body = Body;
mail.IsBodyHtml = true;
//SmtpClient client = new SmtpClient();
using (SmtpClient client = new SmtpClient())
{
client.EnableSsl = true;
client.UseDefaultCredentials = false;
client.Credentials = new NetworkCredential(User.Identity.Name, "RecurveBow");
client.Host = "smtp.live.com";
client.Port = 587;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.Send(mail);
}
return RedirectToAction("BookingDetails", "Home");
}
}
SetDepartureandArrival();
return View();
}
有效，但[t,y]=ode45(@MM2, tspan, y0,[],k1,k2,k3)没有。
非常感谢提前。
答案 0 :(得分：0)
据我了解，当要集成的功能位于另一个文本文件中时，将使用“ @”。如果函数在同一文本文件中，则无需使用“ @”。
例如：让我们计算Van Der Pol摆的水平坐标。
在文件1中：xdot_van_der_pol.m
function dxdt = xdot_van_der_pol(t, x)
global u;
if size(u,1) == 0
u = 1
end
dx1 = x(2);
dx2 = u*(1 - x(1)^2)*x(2) - x(1);
dxdt = [ dx1 ; dx2 ];
在文件2中：Integration.m
u = 1;
tf = 20;
xo = [2 ; 0];
[t,x]=ode45(@xdot_van_der_pol, [0 tf], xo);
subplot(221); plot(x(:,1), t(:,1)); hold on;
subplot(224); plot(t(:,1), x(:,2)); hold on;
subplot(223); plot(x(:,1), x(:,2)); hold on;
另一种情况是将所有内容都写在同一个文本文件中，因此您不必使用“ @”来调用该函数。