how to use function "find" over matrices

Suppose x = rand(1e5,1e5);
I want to find the lowest number in each column of x without using for loop.
Is it possible?

 Respuesta aceptada

Stephen23
Stephen23 el 10 de Abr. de 2020
"find the first value in each column which lis ess than 0.25 but greater than 0.2."
>> x = rand(13,7)
x =
0.833676 0.654529 0.869031 0.922756 0.586565 0.278136 0.595271
0.335144 0.936490 0.552751 0.676447 0.924786 0.813253 0.388776
0.171351 0.992074 0.426227 0.814150 0.599205 0.378885 0.470132
0.368957 0.162066 0.044178 0.911514 0.431260 0.111011 0.348894
0.787866 0.150796 0.783209 0.406310 0.116503 0.232302 0.350849
0.676606 0.782741 0.251472 0.223849 0.872576 0.665249 0.287961
0.176415 0.750830 0.958001 0.274026 0.107420 0.716966 0.612980
0.030644 0.103396 0.297286 0.256401 0.902245 0.486087 0.812681
0.563573 0.414845 0.615615 0.335131 0.589437 0.396942 0.780523
0.994748 0.314337 0.721215 0.946815 0.446822 0.252527 0.593235
0.438298 0.516228 0.978322 0.183097 0.011558 0.731435 0.948024
0.496606 0.172242 0.224708 0.339960 0.425773 0.730056 0.809002
0.234744 0.195880 0.086287 0.702632 0.708232 0.489843 0.558111
>> y = x>0.2 & x<0.25;
>> [row,col] = find(y & cumsum(y,1)==1)
row =
13
12
6
5
col =
1
3
4
6

Más respuestas (1)

David Hill
David Hill el 9 de Abr. de 2020
min(x);

3 comentarios

parham kianian
parham kianian el 9 de Abr. de 2020
Editada: parham kianian el 9 de Abr. de 2020
Let me to clarify the question.
Suppose it is aimed to find the first value in each column which lis ess than 0.25 but greater than 0.2.
How can I do that?
x = rand(1e4);
a = x.*(x>.2&x<.25);
b=arrayfun(@(y)a(find(a(:,y),1),y),1:size(a,2));
parham kianian
parham kianian el 10 de Abr. de 2020
Thank you David. It works well. But the method suggested by Stephen is a little easier.

Iniciar sesión para comentar.

Categorías

Más información sobre Creating and Concatenating Matrices en Centro de ayuda y File Exchange.

Etiquetas

Preguntada:

el 9 de Abr. de 2020

Comentada:

el 10 de Abr. de 2020

Community Treasure Hunt

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

Start Hunting!

Translated by