interp2 error: The grid vectors must be strictly monotonically increasing.

Question

lei zhang 2017-5-10

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/339659-interp2-error-the-grid-vectors-must-be-strictly-monotonically-increasing

回答： Steven Lord 2017-5-10

The error is that "the grid vector must be strictly monotonically increasing" I am confused by this, because the vector a1 and b1 is absolutely monotonic.

%% plot segment1 int=1; % interval of mesh method='nearest'; s1x=Segment1new(:,3); s1y=Segment1new(:,4); s1z=Segment1new(:,5);

mins1x=ceil(min(s1x)); maxs1x=fix(max(s1x)); mins1y=ceil(min(s1y)); maxs1y=fix(max(s1y));

a1=(mins1x:int:maxs1x); b1=(mins1y:int:maxs1y);

[S1X,S1Y]=meshgrid(a1,b1); %produce mesh grid S1Z=interp2(s1x,s1y,s1z,S1X,S1Y,method);%interpolate ZZ mesh(S1X,S1Y,S1Z) hold on

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

Steven Lord 2017-5-10

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/339659-interp2-error-the-grid-vectors-must-be-strictly-monotonically-increasing#answer_266440

在 MATLAB Online 中打开

The query points do not need to be strictly monotonically increasing. The points at which the data to be interpolated is specified do need to be strictly monotonically increasing.

% Generate sample data
[Xmono, Ymono] = meshgrid(-3:3, -3:3);
Xnon = Xmono(randperm(7), randperm(7));
Ynon = Ymono(randperm(7), randperm(7));
V = Xmono + Ymono;
% Interpolate using the monotonically increasing X and Y data as the first two inputs
Vq1Succeeds = interp2(Xmono, Ymono, V, Xnon, Ynon);
szVq1 = size(Vq1Succeeds)
% Interpolate using the non-monotonically increasing X and Y data as the first two inputs
Vq2Fails = interp2(Xnon, Ynon, V, Xmono, Ymono);
szVq2 = size(Vq2Fails)