simplify my script?
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hello, I need some suggestion
I know my code isn't perfect, but this is enough for me. just wondering if my code could be more compact or simpler. the point is the same only different in the grouping per 10 days. I only want to run my code once. here is my code.
for n=1:12
% Load data
ncfile = 'Temperature.nc';
months = {'January', 'February', 'March', 'April', 'May', 'June', ...
'July', 'August', 'September', 'October', 'November', 'December'};
% to read a variable 'var' exisiting in nc file
lon = ncread(ncfile,'longitude');
lat = ncread(ncfile,'latitude');
tempI = ncread(ncfile,'t2m');
% grup date
startDate = datetime(2021,1,1,0,0,0);
endDate = datetime(2021,12,31,23,0,0);
dates = startDate:hours(1):endDate;
%% pick each 10 days data
Onemonth = dates.Month==n ;
t = dates(Onemonth) ;
Ddays = t.Day<=10 ; %date 1-10
% Ddays = t.Day >= 11 & t.Day <=20 ; % date 11-20
% Ddays = t.Day >= 21 & t.Day <=31 ; % date 21-31
%%
% Extract data per month
t10days = tempI(:,:,Ddays);
% rotate data
tempII = flipud(rot90(t10days));
% Average data
temp = mean((tempII-273.15),3);
% Plot
figure
imagescn(lon,lat,temp);
colormap jet
axis image
end
for n=1:12
% Load data
ncfile = 'Temperature2m.nc';
months = {'January', 'February', 'March', 'April', 'May', 'June', ...
'July', 'August', 'September', 'October', 'November', 'December'};
% to read a variable 'var' exisiting in nc file
lon = ncread(ncfile,'longitude');
lat = ncread(ncfile,'latitude');
tempI = ncread(ncfile,'t2m');
%% grup date
startDate = datetime(2021,1,1,0,0,0);
endDate = datetime(2021,12,31,23,0,0);
dates = startDate:hours(1):endDate;
%% pick each 10 days data
Onemonth = dates.Month==n ;
t = dates(Onemonth) ;
% Ddays = t.Day<=10 ; %date 1-10
Ddays = t.Day >= 11 & t.Day <=20 ; % date 11-20
% Ddays = t.Day >= 21 & t.Day <=31 ; % date 21-31
%%
% Extract data per month
t10days = tempI(:,:,Ddays);
% rotate data
tempII = flipud(rot90(t10days));
% Average data
temp = mean((tempII-273.15),3);
%% Plot
figure
imagescn(lon,lat,temp);
colormap jet
axis image
end
for n=1:12
%% Load data
ncfile = 'Temperature2m.nc';
months = {'January', 'February', 'March', 'April', 'May', 'June', ...
'July', 'August', 'September', 'October', 'November', 'December'};
% to read a variable 'var' exisiting in nc file
lon = ncread(ncfile,'longitude');
lat = ncread(ncfile,'latitude');
tempI = ncread(ncfile,'t2m');
%% grup date
startDate = datetime(2021,1,1,0,0,0);
endDate = datetime(2021,12,31,23,0,0);
dates = startDate:hours(1):endDate;
%% pick each 10 days data
Onemonth = dates.Month==n ;
t = dates(Onemonth) ;
% Ddays = t.Day<=10 ; %date 1-10
% Ddays = t.Day >= 11 & t.Day <=20 ; % date 11-20
Ddays = t.Day >= 21 & t.Day <=31 ; % date 21-31
%%
% Extract data per month
t10days = tempI(:,:,Ddays);
% rotate data
tempII = flipud(rot90(t10days));
% Average data
temp = mean((tempII-273.15),3);
%% Plot
figure
imagescn(lon,lat,temp);
colormap jet
axis image
end
3 个评论
Dyuman Joshi
2022-6-28
The 3 loops are identical except for the data file, even then 2nd and 3rd loop loads the same file.
What is your changing variable in all the codes? The file?
You can make your code a function file and call accordingly.
Den
2022-6-28
Dyuman Joshi
2022-6-28
See Jan's answer.
采纳的回答
Jan
2022-6-28
Move all repeated work out of the loops. In your case:
% Load data
ncfile = 'Temperature.nc';
months = {'January', 'February', 'March', 'April', 'May', 'June', ...
'July', 'August', 'September', 'October', 'November', 'December'};
% to read a variable 'var' exisiting in nc file
lon = ncread(ncfile,'longitude');
lat = ncread(ncfile,'latitude');
tempI = ncread(ncfile,'t2m');
% grup date
startDate = datetime(2021,1,1,0,0,0);
endDate = datetime(2021,12,31,23,0,0);
dates = startDate:hours(1):endDate;
Do this once before all loops, because it does not depend on the loop counter n.
3 个评论
Moreover, the only thing that changes in your loop is the Ddays line, you could define your range of days before the loop and loop for all your wanted ranges:
%Create day_range arrays, first column is low value second is high; each
%row is a new range of selected days
Day_range = [1,10; 11, 20; 21, 31]
for i_day = 1:size(Day_range,1)
for n = 1:12
%% pick each 10 days data
Onemonth = dates.Month==n ;
t = dates(Onemonth) ;
Ddays = t.Day >= Day_range(i_day,1) & t.Day <= Day_range(i_day,2) ;
% Extract data per month
t10days = tempI(:,:,Ddays);
% rotate data
tempII = flipud(rot90(t10days));
% Average data
temp = mean((tempII-273.15),3);
%% Plot
figure(i_day) %new figure for each range
imagescn(lon,lat,temp);
colormap jet
axis image
end
end
Den
2022-6-28
Ddays = (t.Day >= Day_range(i_day,1) & t.Day <= Day_range(i_day,2));
This replies a logical vector, which is TRUE, if the element of t.Day is inside the specified range.
for i_day = 1:size(Day_range,1)
Of course, if the corresponding size equal 3, you can write 3 also. But this approach is more general and determines the size dynamically. It is a good programming practice to write flexible code without assumptions about the inputs.
Replace
flipud(rot90(t10days));
by the more direct:
permute(t10days, [2, 1, 3]);
Or even better:
t10days = tempI(:,:,Ddays);
tempII = flipud(rot90(t10days));
temp = mean((tempII-273.15),3);
by the cheaper and simpler:
temp = mean(tempI(:, :, Ddays), 3).' - 273.15;
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