フィルターのクリア

using find-command to find max or min value

5 ビュー (過去 30 日間)
Moustafa Abedel Fattah
Moustafa Abedel Fattah 2022 年 6 月 26 日
Please I need your help to estimate the value of min or max of abs(Y) and its corresponding (X) for attached curve (X versus X ) using (find)-command. In addition want plot a line of corresponding (X) and (Y).
Thanks in advance for all.
Best Regards;
  1 件のコメント
Moustafa Abedel Fattah
Moustafa Abedel Fattah 2022 年 6 月 26 日
Thanks a lot for your quick response as usual. It is works very good and I will more appreciate if you solve it also with (find) command.
Thanks in advance
Best Regards;

サインインしてコメントする。

採用された回答

Star Strider
Star Strider 2022 年 6 月 26 日
This is relatively straightforward. Use max with two outputs:
x = 0:13;
y = randi(25,1,14)/100;
[ymax,idx] = max(y)
ymax = 0.2400
idx = 13
figure
plot(x, y)
hold on
plot([1 1]*x(idx), [min(ylim) ymax], '-r')
plot([0 x(idx)], [1 1]*ymax, '-r')
hold off
grid
Experiment with your data.
.
  1 件のコメント
Star Strider
Star Strider 2022 年 6 月 27 日
As always, my pleasure!
Using find is straghtforward —
x = 0:13;
y = randi(25,1,14)/100;
idx = find(y == max(y))
idx = 10
figure
plot(x, y)
hold on
plot([1 1]*x(idx), [min(ylim) y(idx)], '-r')
plot([0 x(idx)], [1 1]*y(idx), '-r')
hold off
grid
That requires essentially the same code.
.

サインインしてコメントする。

その他の回答 (1 件)

Image Analyst
Image Analyst 2022 年 6 月 26 日
I prefer using the find function in combination to find max and min locations. The reason being if the max occurs at more than one location, max only gives you the location of the first one. I've asked them for many, many years to return the index(es) of all max in the vactor.
y = [1 3 2 3 0] % Max at index 2 and 4
y = 1×5
1 3 2 3 0
[maxValue, indexes] = max(y) % Only gives you the one at index 2 not at 4.
maxValue = 3
indexes = 2

カテゴリ

Help Center および File ExchangeOptimization についてさらに検索

Community Treasure Hunt

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

Start Hunting!

Translated by