# Conditional if statement solution

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Tino on 15 Aug 2019
Answered: Rik on 15 Aug 2019
I will greatly appreciate it if any one assist me in solving this problem in Matlab code
For instance I have a list of values = 3 4 6 3 4 5 10 7 4 5 3 4
The code contains two if statement
if values > 9
in this case it is in position 7 : display the positions in values that meet condition ( if value > 9) in the example above it is the 7th position (10)
then calculate the 5 numbers before and after including position 7th (10) itself an example
average = (4 + 5 + 10 + 7 + 4 )/5 = 6
if (average > 9)
true changes showing ( 7th position = 10 )
else
false changes (7th position = 10 )
end if statement
end if statement
The answer is false change detection
I will like to be assisted with the code as I want to apply these to large data

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Tino on 15 Aug 2019
Yes Geoff it is applicable for all elements with a value greater than 9 even if it is more than one.
Geoff Hayes on 15 Aug 2019
So you will want to find all elements that are greater than nine and then apply the logic to each one presumably storing the result of each in an array.
Tino on 15 Aug 2019
Yes Geoff with a discription if they are true changes or false changes

Rik on 15 Aug 2019
In Matlab calculating parameters for the entire array at once is almost always faster than a loop. My code below uses the find function (as Geoff hinted at), and it uses a convolution to find the moving average for each position. You should check if this matches your requirements for the edge cases. If you want to display the results in a different way, you should be able to add code that suits your need.
values =[3 4 6 3 4 5 10 7 4 5 3 4];
window=ones(1,5)/5;
avg=conv(values,window,'same');
true_changes=find( values>9 & avg>9 );
false_changes=find( values>9 & avg<=9 );