MATLAB Programming

6 Data Import and Export
d = m.Data;
Writeallzerostothecopy:
d(2).x(1:5,1:8) = 0;
d(2).x
ans =
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
Verify that the data in the mapped file has not changed even though the copy
of m.Data(2).x has been written with zeros:
m.Data(2).x
ans =
35330 4902 31861 16877 23791 61500 52748 16841
51314 58795 16860 43523 8957 5182 16864 60110
18415 16871 59373 61001 52007 16875 26374 28570
16783 4356 52847 53977 16858 38427 16067 33318
65372 48883 53612 16861 18882 39824 61529 16869
Invalid Syntax for Writing to Mapped Memory
Although you can expand the dimensions of a typical MATLAB array by
assigning outside its current dimensions, this does not apply to the Data
property of a memmapfile object. The following operation is invalid if m.Data
has only 100 elements:
m.Data(120) = x;
Ifyouneedtoexpandthesizeofthemappeddataregion,firstextendthemap
by updating the Format or Repeat property of the memmapfile object to reflect
the new structure of the data in the mapped file.
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