MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

### Discover what MATLAB® can do for your career.

Opportunities for recent engineering grads.

# Thread Subject: Griding data

 Subject: Griding data From: Shaik Ghouse Basha Date: 4 Apr, 2012 03:14:15 Message: 1 of 5 Dear Friends, I am facing problem in Griding data in matlab. I have written the code but its taking sooo much time to process. My data contains X(longitude) Y(latitude) Z(data points) with 0.5 degree resolution. I have to make this data gridding with 1.5x1.5 degree resolution. please help me how to save the time and also i have gone through all the griding programs in mathworks.com.
 Subject: Griding data From: Nasser M. Abbasi Date: 4 Apr, 2012 03:32:49 Message: 2 of 5 On 4/3/2012 10:14 PM, Shaik Ghouse Basha wrote: > Dear Friends, I am facing problem in Griding data in matlab. >I have written the code but its taking sooo much time to process. >My data contains X(longitude) Y(latitude) Z(data points) with 0.5 degree >resolution. I have to make this data gridding with 1.5x1.5 degree > resolution. please help me how to save the time and also i have gone >through all the griding programs in mathworks.com. It will help others help you more by making small example of the problem, post the complete code of the small example here. Hard to help you without seeing anything. --Nasser
 Subject: Griding data From: Shaik Ghouse Basha Date: 4 Apr, 2012 03:51:26 Message: 3 of 5 I have X Y Z of length 13000 like this i have 16700 columns of data for j=1 eps1=1.5;         Eda=nan(length(lat1),length(lon1));         for k=1:length(Z)                          P1=find(lat1>=Y(k)-eps1 & lat1<=Y(k)+eps1);             Q1=find(lon1>=X(k)-eps1 & lon1<=X(k)+eps1);             if length(P1)>1                 P1=P1(1);             end             if length(Q1)>1                 Q1=Q1(1);             end                          Eda(P1,Q1)=nanmean([Eda(P1,Q1) Z(k)]);         end end "Nasser M. Abbasi" wrote in message ... > On 4/3/2012 10:14 PM, Shaik Ghouse Basha wrote: > > Dear Friends, I am facing problem in Griding data in matlab. > >I have written the code but its taking sooo much time to process. > >My data contains X(longitude) Y(latitude) Z(data points) with 0.5 degree > >resolution. I have to make this data gridding with 1.5x1.5 degree > > resolution. please help me how to save the time and also i have gone > >through all the griding programs in mathworks.com. > > It will help others help you more by making small example > of the problem, post the complete code of the small example > here. > > Hard to help you without seeing anything. > > --Nasser >
 Subject: Griding data From: Andrew Stevens Date: 4 Apr, 2012 14:06:09 Message: 4 of 5 "Shaik Ghouse Basha" wrote in message ... > I have X Y Z of length 13000 like this i have 16700 columns of data > for j=1 > eps1=1.5; > Eda=nan(length(lat1),length(lon1)); > for k=1:length(Z) > > P1=find(lat1>=Y(k)-eps1 & lat1<=Y(k)+eps1); > Q1=find(lon1>=X(k)-eps1 & lon1<=X(k)+eps1); > if length(P1)>1 > P1=P1(1); > end > if length(Q1)>1 > Q1=Q1(1); > end > > Eda(P1,Q1)=nanmean([Eda(P1,Q1) Z(k)]); > end > end > > "Nasser M. Abbasi" wrote in message ... > > On 4/3/2012 10:14 PM, Shaik Ghouse Basha wrote: > > > Dear Friends, I am facing problem in Griding data in matlab. > > >I have written the code but its taking sooo much time to process. > > >My data contains X(longitude) Y(latitude) Z(data points) with 0.5 degree > > >resolution. I have to make this data gridding with 1.5x1.5 degree > > > resolution. please help me how to save the time and also i have gone > > >through all the griding programs in mathworks.com. > > > > It will help others help you more by making small example > > of the problem, post the complete code of the small example > > here. > > > > Hard to help you without seeing anything. > > > > --Nasser > > you might find this function useful: http://www.mathworks.com/matlabcentral/fileexchange/23479-bin2mat It is not optimized for speed, but may be faster than your current code. -Andrew
 Subject: Griding data From: TideMan Date: 4 Apr, 2012 04:39:03 Message: 5 of 5 On Wednesday, April 4, 2012 3:51:26 PM UTC+12, Shaik Ghouse Basha wrote: > I have X Y Z of length 13000 like this i have 16700 columns of data > for j=1 > eps1=1.5; > Eda=nan(length(lat1),length(lon1)); > for k=1:length(Z) > > P1=find(lat1>=Y(k)-eps1 & lat1<=Y(k)+eps1); > Q1=find(lon1>=X(k)-eps1 & lon1<=X(k)+eps1); > if length(P1)>1 > P1=P1(1); > end > if length(Q1)>1 > Q1=Q1(1); > end > > Eda(P1,Q1)=nanmean([Eda(P1,Q1) Z(k)]); > end > end > > "Nasser M. Abbasi" wrote in message ... > > On 4/3/2012 10:14 PM, Shaik Ghouse Basha wrote: > > > Dear Friends, I am facing problem in Griding data in matlab. > > >I have written the code but its taking sooo much time to process. > > >My data contains X(longitude) Y(latitude) Z(data points) with 0.5 degree > > >resolution. I have to make this data gridding with 1.5x1.5 degree > > > resolution. please help me how to save the time and also i have gone > > >through all the griding programs in mathworks.com. > > > > It will help others help you more by making small example > > of the problem, post the complete code of the small example > > here. > > > > Hard to help you without seeing anything. > > > > --Nasser > > Well, I can see why it's taking so long. It's those find commands. They assume your data are randomly distributed, but actually they're in a grid aren't they? In which case, you can reshape the vectors into matrices and apply a bit of intelligence to how you process the data. What are the dimensions of your grid?

## Tags for this Thread

No tags are associated with this thread.

### What are tags?

A tag is like a keyword or category label associated with each thread. Tags make it easier for you to find threads of interest.

Anyone can tag a thread. Tags are public and visible to everyone.