fwrite with fixed length of different data types

8 views (last 30 days)
I have a know format file with different reading format. Example -
fread(fid,[1, 40], 'char')
fread(fid,[1, 4], 'long')
fread(fid,[1, 1], 'short')
% These are data blocks
fread(fid,[400 1],'double')
fread(fid,[400 1],'int')
fread(fid,[400 1],'float')
Now, i have to write the data in the same fashion
something like that -
how can i pad and fwrite of other data structures

Answers (1)

Walter Roberson
Walter Roberson on 26 Dec 2018
40*char is not a permitted fwrite precision .
The precision option is not intended to give information about how many elements are being written: instead it gives information about how each input element is to be represented as output. The number is determined by the size of the variable .
If you need to pad then fwrite the pad values yourself .
for example .
It is not possible to fwrite two different datatypes in one call. (However memory mapping routines can input or output entire structure at a time .)
Walter Roberson
Walter Roberson on 1 Jan 2019
Some time ago I wrote a small function to fwrite() with padding or truncation to a given length. It is easy to do and makes it easier to write out fixed-width structures.

Sign in to comment.


Find more on Large Files and Big Data in Help Center and File Exchange


Community Treasure Hunt

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

Start Hunting!