yes you are right it was named as sign_PV my mistake,actually I changed the name from sign_PV to stress_PV because it was conflicting with the Matlab command. I did what you said but still there is one error it is showing: Subscript indices must eith

yes you are right it was named as sign_PV my mistake,actually I changed the name from sign_PV to stress_PV because it was conflicting with the Matlab command. I did what you said but still there is one error it is showing: Subscript indices must either be real positive integers or logicals.

Error in fatiguelife (line 14) s1=stress_PV(i); I am also attaching the script please find the attachment.

Answer 1

[Walter Roberson]

Your code does not assign any value to i before it uses i

[Prateek Srivastava]

ok so if I assigned the value to i than also it is not working .my goal is to pick up the 1st value from the cleared signal value that is stored in the table stress_PV and go on till the fourth value and than check the conditions for that and if it is true than I would extract that point .I am also attaching the script please find the attachment.

[Walter Roberson]

You have

i=(stress_PV);
while i<length(stress_PV)

In the first of those two lines, you assign contents of the entire stress_PV array to i. In the second of those two lines, you try to compare the contents of that array to the length of what was the array.

I notice that in your code you are deleting entries from stress_PV and then changing the value of i . Is it your intent to potentially remove multiple values from the vector, in an overlapping manner -- so for example if you are "positioned" at entry 5 and you examine entries 5, 6, 7 and 8, and decide to modify entry 5 and delete entries 6 and 7, that you then want to "backtrack" so that next time around you would be checking entries 2, 3, 4 and (now modified) 5 ?

[Prateek Srivastava]

yes

[Walter Roberson]

i=1

[Prateek Srivastava]

it almost worked but there is a problem as I am trying to store these values stress_PV(i+1:i+2)=[]; stress_PV is conflicting with the length of the vector which was original assigned to stress_PV values and therefore it is giving this error when I am running the algorithm Index exceeds matrix dimensions.

Error in fatiguelife (line 18) s4=stress_PV(i+3); I tried changing the variable name but than it is saying it has to be predefined I am attaching the new script and the data also thanks in advance.

[Walter Roberson]

while i<length(stress_PV)-3

[Prateek Srivastava]

it is working but the problem is now it is picking values from stress_PV(i+1:i+2)=[];which I dont want ,I want to pick the value from stress_PV from the first half of the script so I have to do something so that it does not conflict with this line stress_PV(i+1:i+2)=[]; and it still store the value for this line stress_PV(i+1:i+2)=[];

[Walter Roberson]

You have no comments in the code. I have no idea what the code is intended to do. Based upon the question I asked earlier, I do not see any problem with the code: it would appear to do what you have indicated you want to be done.

[Prateek Srivastava]

the difference you could see if I i just non execute this line stress_PV(i+1:i+2)=[]; you could see values stored under the table stress_PV changes but if I don't than the value which S4 operator picks changes from 30 to 20 which is wrong because it has to pick the value from stress_PV but it is not instead it is picking value from this line stress_PV(i+1:i+2)=[] which I dont want.The idea of the code is to pick the the value from the cleared signal obtained in the first part of the script that is assigned under stress_PV and you could see there are 9 set of values from the first part of the script and than in the second part I used while loop to run this iteration code so as to extract the points by using rain flow method formula.

[Walter Roberson]

I asked "you then want to "backtrack" so that next time around you would be checking entries 2, 3, 4 and (now modified) 5" and you said "Yes", so what you are describing as happening seems to be what you have already said you want to happen.

[Prateek Srivastava]

If this conditions is true abs(s2-s1)>=abs(s2-s3)&&abs(s3-s4)>=abs(s2-s3) than I extract the point and I move back so that I could get the iteration correct.