Go Back   MacRumors Forums > Apple Systems and Services > Programming > Mac Programming

Reply
 
Thread Tools Search this Thread Display Modes
Old Mar 1, 2012, 12:45 PM   #1
dukebound85
macrumors P6
 
dukebound85's Avatar
 
Join Date: Jul 2005
Location: 5045 feet above sea level
Code Question

I am trying to do the following.

I have a 7670 array of data
I also have complimentary arrays that are 7670 in length that are the day, month, and year

For instance
data = [1,7670] = [.3,.45,.56,.67, etc].....to index 7670 with just data values
day = [1,2,3,4,5...31,1,2,3,4,....28,1,2,3,4....30] repeating for 7670 indexes. These are the value of the days in the particular month
month = [1,1,1,1,1,(31 times), 2,2,2,2,2,2,(28 times), etc] for 7670 indexes
year = [1980,1980,1980, (365 times), 1981,1981, (365 times),] etc for 7670 indexes

My question is how can I take this daily data and average it for each month...so my 7670 array is about 650 in length

Here is what I have right now. This is matlab
Code:
count = 1;
for i=1:7670
    if i < 7670
        while day(i+1)>day(i)
            k = 1;
            index(count,k) = day(i);
            k = k+1;            
        end
            
            u300_PC1_monthly_avg(count) = mean(u300_PC1(index(count,1):size(index,2)));
            count = count+1;
            i = i+1;
    end
end
dukebound85 is offline   0 Reply With Quote
Old Mar 1, 2012, 12:49 PM   #2
balamw
Moderator
 
balamw's Avatar
 
Join Date: Aug 2005
Location: New England, USA
I'd create a new data array and loop over year then month (nested loops).

Every time you get a change in year or month increment the index of the new structure and start a new average.

Does that help?

EDIT: (Sorry, I missed that it was MATLAB).

You could easily use a sparse matrix instead of the indexed one. Just use Year*100+Month as the index for the sparse matrix. This gives you an easy way to look up the data too.

B
__________________
MBA (13" 1.7 GHz 128GB), UMBP (15" SD 2.8 GHz), UMB (13" 2.4 GHz), iMac (17" Yonah), 32GB iPad 3 WiFi+LTE, 64 GB iPad WiFi, 32 GB iPhone 5, Airport Extreme
balamw is offline   0 Reply With Quote
Old Mar 1, 2012, 01:41 PM   #3
dukebound85
Thread Starter
macrumors P6
 
dukebound85's Avatar
 
Join Date: Jul 2005
Location: 5045 feet above sea level
Quote:
Originally Posted by balamw View Post
I'd create a new data array and loop over year then month (nested loops).

Every time you get a change in year or month increment the index of the new structure and start a new average.

Does that help?

EDIT: (Sorry, I missed that it was MATLAB).

You could easily use a sparse matrix instead of the indexed one. Just use Year*100+Month as the index for the sparse matrix. This gives you an easy way to look up the data too.

B

Sort of. I feel like I could avoid loops but just having a hard time implemeting the logic in my code
dukebound85 is offline   0 Reply With Quote
Old Mar 1, 2012, 01:47 PM   #4
balamw
Moderator
 
balamw's Avatar
 
Join Date: Aug 2005
Location: New England, USA
Start with:

Quote:
imonth = 100*year+month;
That gives you a single variable to loop over.

B
__________________
MBA (13" 1.7 GHz 128GB), UMBP (15" SD 2.8 GHz), UMB (13" 2.4 GHz), iMac (17" Yonah), 32GB iPad 3 WiFi+LTE, 64 GB iPad WiFi, 32 GB iPhone 5, Airport Extreme
balamw is offline   0 Reply With Quote
Old Mar 1, 2012, 04:00 PM   #5
dukebound85
Thread Starter
macrumors P6
 
dukebound85's Avatar
 
Join Date: Jul 2005
Location: 5045 feet above sea level
Quote:
Originally Posted by balamw View Post
Start with:



That gives you a single variable to loop over.

B
Thanks for the suggestion
dukebound85 is offline   0 Reply With Quote

Reply
MacRumors Forums > Apple Systems and Services > Programming > Mac Programming

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Similar Threads
thread Thread Starter Forum Replies Last Post
Library for simple Face and QR Code/Bar Code/Etc detection DarthFoley iPhone/iPad Programming 0 Jan 26, 2014 12:11 PM
Ripit question (code for registration) Primejimbo Apple TV and Home Theater 0 Jan 7, 2013 05:21 PM
My Macintosh 512K is a Sad Mac. Error code question minifridge1138 Apple Collectors 7 Nov 4, 2012 12:10 AM

Forum Jump

All times are GMT -5. The time now is 07:57 AM.

Mac Rumors | Mac | iPhone | iPhone Game Reviews | iPhone Apps

Mobile Version | Fixed | Fluid | Fluid HD
Copyright 2002-2013, MacRumors.com, LLC