# how creat random text file

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Aseel H on 25 May 2013
Edited: Adam Danz on 16 Dec 2020
I need to creat text file have random charecters with spesific size
I need give it size to generate random text file
for example: i need file have 4 character text = "abca"
Jan on 25 May 2013
The question does not have a connection to the term "embedded" yet. Please clarify this.

Azzi Abdelmalek on 25 May 2013
s='a':'z'
n=4
out=s(randi(26,n,1))
##### 2 CommentsShowHide 1 older comment
Azzi Abdelmalek on 25 May 2013
Do you need to write a result to a text file?
Look at fprintf

Adam Danz on 1 Nov 2019
Edited: Adam Danz on 16 Dec 2020
Another idea is to use randsample() to create random letters in the form of words separated by randomized spaces. This function allows you to set weights on the probability of each letter being drawn so you could use real letter frequencies for a laguage and then assign a frequency for spaces that controls the average word length.
Here's a demo using relative frequencies of English letters and an average words length of 5 letters.
% Desired avg word length (approximate)
wordLen = 5;
% Number of characters to produce
nchar = 100;
% Relative frequencies for each letter a:z
% https://en.wikipedia.org/wiki/Letter_frequency
freq = [ 8.167 1.492 2.782 4.253 12.702 2.228 2.015 6.094 6.966 ...
0.153 0.772 4.025 2.406 6.749 7.507 1.929 0.095 5.987 6.327 ...
9.056 2.758 0.978 2.36 0.15 1.974 0.074]./100 .*(1-1/wordLen);
% Re-weight the frequencies based on word length ^^^^^^^^^^^^^^^^
% To create a uniform frequency for each letter: freq = [1/wordLen,(1-1/wordLen)/26*ones(1,26)];
% The line below creates a character array of randomized lower case
% latin letters and spaces with a typical word length of 5 letters.
str = char(randsample([32,'a':'z'],nchar,true,[1/wordLen,freq]));
% [1] [2] [3]
% [1] 32 is the ascii value for [space]
% [2] 100 random characters will be generated
% [3] 1/5 to approximate a mean word length of 5 (for n letter words, use 1/n)
% Example output
disp(str)
a eeag rutetcaders odiodd wqeras dlwfwrtct hehwyaeina ushbr ao argcernpd h t dos ekksn dceeoeut h
% If desired, split the "words" into cell array of chars.
c = strsplit(str)
c = 1x16 cell array
{'a'} {'eeag'} {'rutetcaders'} {'odiodd'} {'wqeras'} {'dlwfwrtct'} {'hehwyaeina'} {'ushbr'} {'ao'} {'argcernpd'} {'h'} {'t'} {'dos'} {'ekksn'} {'dceeoeut'} {'h'}
% Let's see if the average word length is indeed what we set
% it to (5 in this demo)
slen = strlength(c);
mean(slen) % Yes, on average the words are 5 letters long
ans = 5.1250