A matrix/grid from two vectors

2021 3 12
1 个回答
回答已采纳
更新时间：2021 3 12
33 次查看（30 天）

0 个投票

Dear all,
I am trying to construct a matrix (or a grid) with specific limits on the x and y axes from two vectors:
ns = 20; %number of points on S axis
np = 20; %number of points on P axis
S = linspace(0,1,ns); %S variable
P = linspace(-1,1,np); %P variable
The resulting grid I want has the follwoing shape (just for an illustrative purpose. Surely the number of points would be larger):
I have thought about "meshgrid(S,P)" command, but it won't help as it doesn't let me have the specific P limits that I want, as shown in the photo above.
Any help would be appreicated!
Thanks,
Lama

请先登录，再回答此问题。

 采纳的回答

Cris LaPierre
Cris LaPierre 2021-3-12

0 个投票

meshgrid creates the matrices of x and y coordinates you wlil need to plot a mesh/surface plot.
Lookin at the examples on the mesh documentation page for how to use these two functions.

4 个评论
显示 2更早的评论 隐藏 2更早的评论

Lama Hamadeh
Lama Hamadeh 2021-3-12
Thank you for your answer. However, although meshgrid will generate a grid of the same size that I want, but it won't let me access each grid cell (or pixel) of the grid. Also, it would be hard (I guess) to strict the limit of the y axis to be from -1 to 1 and the x axis to be from 0 to 1. When using meshgrid, it generates two axes with the same limits.
Cris LaPierre
Cris LaPierre 2021-3-12
编辑：Cris LaPierre 2021-3-12
Meshgrid does not create axes. It creates matrices that can be used as the coordinates (x and y, or in your case, S and P).
To place a point in a 2D grid, you need the X and Y values. To access a value, you need its index number in the vector/matrix.
Cris LaPierre
Cris LaPierre 2021-3-12
Ran in:
Ran in:
ns = 20; %number of points on S axis
np = 20; %number of points on P axis
s = linspace(0,1,ns); %S variable
p = linspace(-1,1,np); %P variable
[S,P] = meshgrid(s,p);
% mesh needs X,Y and Z so create z
Z = zeros(size(S));
mesh(S,P,Z,'Marker','o','MarkerFaceColor','k','EdgeColor',"k")
axis equal tight
view(2)
Lama Hamadeh
Lama Hamadeh 2021-3-12
Great! Many thanks!

请先登录，再进行评论。

更多回答（0 个）

类别

在 帮助中心 和 File Exchange 中查找有关 Creating and Concatenating Matrices 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by