I keep getting this error:Index exceeds matrix dimensions.

Question

rania 2014-8-8

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/146796-i-keep-getting-this-error-index-exceeds-matrix-dimensions

编辑： Andrew Reibold 2014-8-8

I keep getting this error:Index exceeds matrix dimensions. Error in ==> D:\toolbox\matlab\funfun\pdepe.m (pdeodes) On line 338 ==> up(j,i) = (xim(i) * fR(j) - xim(i-1) * fL(j)) + ...

Error in ==> D:\toolbox\matlab\funfun\private\odearguments.m On line 104 ==> f0 = feval(ode,t0,y0,args{:});

Error in ==> D:\toolbox\matlab\funfun\ode15s.m On line 212 ==> [neq, tspan, ntspan, next, t0, tfinal, tdir, y0, f0, args, ...

Error in ==> D:\toolbox\matlab\funfun\pdepe.m On line 287 ==> [t,y] = ode15s(@pdeodes,t,y0,opts,pde,ic,bc,m,xmesh,xi,xim,zxmp1,xzmp1,varargin{:});

Error in ==> D:\work\kinetics.m On line 19 ==> Cis= pdepe(m,@pdecoefsr,@pdeicsr,@pdebcsr,x,t)

the main Mfile names kinetics %input Cio=13.5 ; %initial concentration Rp=.002 ; %radius of particals m epsilon=.5; %porosity kf2 = 0.04; Di=6*10^-8 ; % diffuision coefficient in catalyst k = .035; Ke=4.95 rs=1 Xi=1 taw=Rp^2/Di time=2*60 t=time/taw %initialization m=0 x = linspace(0,1,20); t = [0 0.5 1 1.5 2]; Cis= pdepe(m,@pdecoefsr,@pdeicsr,@pdebcsr,x,t)

function[pl,ql,pr,qr]=pdebcsr(xl,ul,xr,ur,t) global Xi

pl =ul; ql =0; pr =Xi-1; qr =0; end

function [c,b,s]=pdecoefsr(x,t,u,DuDx) global kf2 Rp Cis Ke epsilon Cio

c = 1; b =DuDx; s = -epsilon*kf2*Cio*(Rp^2)*(Cis^2-((1-Cis)/Ke)); end

function u0=pdeicsr(x)

u0=0; end

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Andrew Reibold 2014-8-8

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/146796-i-keep-getting-this-error-index-exceeds-matrix-dimensions#answer_147936

编辑：Andrew Reibold 2014-8-8

在 MATLAB Online 中打开

'You cannot try to access part of an array that does not exist yet.

>> A = [1,3];
>> A(3)

Index exceeds matrix dimensions

Unfortunately, MATLAB doesn't tell you which variable you exceeded the dimensions on if there's more than one so you'll have to check that. This often occurs if, for example, you are using a loop to change which part of an array is accessed, but the loop doesn't stop before you reach the end of the array. This also happens if you end up with an empty matrix as a result of some operation and then try to access an element inside it.'

I recommend putting breaks in your code before the error so you can check the index value and check the arrays your are using so that you can identify where the problem is coming from.

http://en.wikibooks.org/wiki/MATLAB_Programming/Error_Messages#Indexing_errors