Plot a drawn, filled shape at each data point

DrEamonn さんによって質問されました 2019 年 3 月 21 日

最新アクティビティ Star Strider さんによってコメントされました 2019 年 3 月 22 日

75 ビュー (過去 30 日間)

I have a matrix which contains X & Y data for seperate, single point locations to be plotted on a map using a marker for each point (kind of like multiple 'X marks the spot' on a map)

This works well until I scale the figure window & then the markers become a lot smaller than the data they represent.

How would I plot a filled unit square centred on each data point e.g. if the first point to be plotted is at (50, 10) I would like to draw a square (49.5, 9.5) (50.5, 9.5) (50.5, 10.5) (49.5, 10.5) & fil the square in a particular colour?

0 件のコメント

サインイン to comment.

3 件の回答

リンク

Answer by dpb on 21 Mar 2019

Edited by dpb on 21 Mar 2019

S=1;                                       % Side size
X=50; Y=10;                                % location
hR=rectangle('Position',[X-S/2,Y-S/2,S,S],'FaceColor','k');
xlim([X-5*S X+5*S]), ylim([Y-5*S Y+5*S])
hAx=gca;
grid on

2 件のコメント

DrEamonn on 21 Mar 2019

Solution is almost there, but position vectors have multiple values i.e.

X = [10 20 30]

Y = [15 10 5]

I have tried creating the w & h elements as w = ones(size(X)) & passing the rectangle function

rectangle( X, Y, w, h)

dpb on 21 Mar 2019

doc arrayfun

with anonymous function...

arrayfun(@(x,y) rectangle('Position',[x-S/2,y-S/2,S,S],'FaceColor'),'k',X,Y)

S is value set before definition.

サインイン to comment.

リンク

Answer by DrEamonn on 21 Mar 2019

rectangles function appears to do what I need

https://uk.mathworks.com/matlabcentral/fileexchange/59243-rectangles

0 件のコメント

サインイン to comment.

リンク

Answer by Kelly Kearney on 21 Mar 2019

A single multi-faceted patch will render more quickly than lots of individual rectangles. And this option allows your marker to be any arbitrary shape:

X = [10 20 30] 
Y = [15 10 5]
xsquare = [0 0 1 1 0]';
ysquare = [0 1 1 0 0]';
hrect = patch(X+xsquare, Y+ysquare, 'k')

2 件のコメント

DrEamonn on 22 Mar 2019

Hi Kelly

I can see what you are suggesting to do, but I can't get it to work. Running your code gives me

Error using  + 
Matrix dimensions must agree.

Star Strider on 22 Mar 2019

If you’re using R2016a or earlier (so do not have ‘automatic implicit expansion’) you need slightly different code:

Xxsq = bsxfun(@plus, X, xsquare)
Yysq = bsxfun(@plus, Y, ysquare)
hrect = patch(Xxsq, Yysq, 'k')

サインイン to comment.

サインインしてこの質問に回答します。

現在この質問をフォロー中です

DrEamonn (view profile)