Is their any way to load only selected fields from a saved structure array.

조회 수: 51(최근 30일)
Bonnie Tyler
Bonnie Tyler 2017년 2월 15일
댓글: Walter Roberson 2017년 2월 15일
I have some very large structure arrays stored in .mat files. I want to avoid loading the entire array to save time and memory.

답변(2개)

Stephen23
Stephen23 2017년 2월 15일
편집: Stephen23 2017년 2월 15일
Method
Make sure you save the structure array using the '-struct' option:
save(filename,'-struct','S')
And then, exactly as the load documentation says, you can load the variables by supplying their names as optional arguments. E.g. if the mat file contains variables X and Y:
S = load(filename,'X','Y');
This will only load X and Y into the structure S, not matter what other variables are also present in the mat file.
Example
>> S.X = 1:3;
>> S.Y = 4:5;
>> S.Z = 6:9;
>> save('test.mat','-struct','S')
>> clear
>> S = load('test.mat','X','Y');
>> fieldnames(S)
ans =
'X'
'Y'
>> S.Y
ans =
4 5
  댓글 수: 1
Walter Roberson
Walter Roberson 2017년 2월 15일
However, if they are structure arrays rather than scalar structures, then you cannot use save -struct

댓글을 달려면 로그인하십시오.


Walter Roberson
Walter Roberson 2017년 2월 15일
Sorry there is no Mathworks provided way to do that.
If you just happen to be using a v7.3 mat file then I wonder if there would be an approach by using hdf5 routines to access the mat file?

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by