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Magnitude, row and column in a Matrix

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Good Morning.
I have a matrix A
A = [87.97 87.97 17.97
95.22 87.96 91.26
75.50 75.50 75.50
78.13 64.89 78.90];
What instructions should I do to get
Minimum value per column
The line and column of that value
The result would be:
magnitude 75.50 64.89 17.97
row 3 4 1
column 1 2 3
Greetings and thanks

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Accepted Answer

Star Strider
Star Strider on 22 Jan 2020
Try this:
A = [87.97 87.97 17.97
95.22 87.96 91.26
75.50 75.50 75.50
78.13 64.89 78.90];
[MaxA,MaxRow] = max(A)
[MinA,MinRow] = min(A)
producing:
MaxA =
95.2200 87.9700 91.2600
MaxRow =
2 1 2
MinA =
75.5000 64.8900 17.9700
MinRow =
3 4 1

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Star Strider
Star Strider on 22 Jan 2020
As always, my pleasure.
The minimum of each column is in the ‘minA’ result:
MinA =
75.5000 64.8900 17.9700
The same is true for the code for the maximum for each column, returned in ‘maxA’.
The maximum row and column for ‘A’ is:
[RowMax,ColMax] = find(A == max(A(:)))
Ricardo Gutierrez
Ricardo Gutierrez on 23 Jan 2020
This is the code I have, with your suggestions.
______________________________________________
clc; clear; close all; format short;
A=[ 87.97 87.97 17.97
95.22 87.96 91.26
75.50 75.50 75.50
78.13 64.89 78.90];
[MinA,MinRow] = min(A)
[RowMin,ColMin] = find(A == min(A(:)))
__________________________________________________
This is the results show in the Command Window
______________________________________________
MinA =
75.5000 64.8900 17.9700
MinRow =
3 4 1
RowMin =
1
ColMin =
3
ColMin =
3
>>
___________________________________________
As we see it does not show me the columns.
It shows me only one
Already the minimum values and the rows are resolved, only the columns are missing.
Thanks for your help
Star Strider
Star Strider on 23 Jan 2020
It actually shows everything you want it to show.

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More Answers (1)

Walter Roberson
Walter Roberson on 22 Jan 2020
Use the two output form of min(). The second output will be the appropriate row numbers.

  3 Comments

Ricardo Gutierrez
Ricardo Gutierrez on 22 Jan 2020
Hi.
Thanks for your help.
With your suggestion I would know the magnitude of the minimum value and the row number it is. Now I need to know in which column this value is.
The actual matrix is 20 X 18
Greetings and thanks
Walter Roberson
Walter Roberson on 23 Jan 2020
The column number is 1:number of columns

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