How can I find the index of the maximum Value in a given subintervall in the normal array

Hi community,

first time asking a question here. I am currently dealing with task involving this problem:

For simplification, lets say, I have two corresponding arrays:

Current_array = [0 1 2 3 4 5];

Voltage_array = [1 2 3 4 5 6];

I want to find the index of the maximum Value in the current_array, but only in the regime, where the corresponding Voltage_array is smaller than 2:

[~,index] = max ( (Current_array (Voltage_array > 2) ) );

My output index would be 4, since the largest value of my subarray (Current_array (Voltage_array > 2) ) = [3 4 5 6] is at position 4.

But what I really want is to find the index of that maximum value in my Current_array, which would be index = 6.

Is there an elegent way to solve this?

Answer 1

[David Hill]

[~,index]=max(Current_array.*(Voltage_array>2));

[Kaihua Zhang]

Hi David,

thanks for answering my question. After using this method for a while, I stumbled across another problem, for which I have not found a solution yet.

Let's say my current array is not sorted like the current array in the initial post, and I want to retrieve the index of the largest value from the Current_array for a Voltage > 1.

Current_array = [1,3,5,2,4];
Voltage_array = [0,1,2,3,4];
[~,index]=max(Current_array.*(Voltage_array>1));

By using your solution, my index output would be index = 5, since the product between both arrays reaches an maximum at the 5th index. But the desired output should be index = 3.

Do you have another workaround for this?

Thanks in advance,

Kai