How to make a connection between a key word and a binary digit?

I have a text 'mail.txt' and I chose a key word 'good'which is repeated 10 times in the text,I have generated a random binary number consists of 10 digits 0100111011 ,the first occurrence of the word 'good' meets the first digit'0' the second occurrence meets digit'1' and so on,How to achieve this and also to say if the the digit is '1' replace 'good'with 'bad' ,else no changes,can I have your help please.

Answer 1

[Walter Roberson]

strfind() 'good', giving back a vector of starting indices. Use the binary vector to select elements out of that array. Make the replacement at each remaining location.

Hint: try looping backwards

[jojototo]

Thanks,but what is meant by looping backwards?

[Walter Roberson]

for K = 10 : -1 : 1

instead of

for K = 1 : 10

[jojototo]

thanks

[jojototo]

How to Use the binary vector to select elements out of that array?

[Walter Roberson]

selected_locs = '0100111011' == '1';
nloc = length(selected_locs);
idx = strfind(S, 'good');
nix = length(idx);
if nix > nloc; selected_locs(nix) = false; end
if nix < nloc; selected_locs(nix+1:end) = []; end
places_to_change = idx(nix);

[Walter Roberson]

for loc = fliplr(places_to_change)
  S = [S(1:loc-1), 'bad', S(loc+4:end)];
end

[jojototo]

I have a problem with the code you have sent ,only the last occurance of the word "good"is replaced by the word"bad" and also process of replacement doesn't depend on the binary digits "if 1 make the replacement and if 0 don't do the replacement" thanks a lot for your efforts

[Walter Roberson]

places_to_change = idx(selected_locs);

[jojototo]

Thank you so much,it works

[jojototo]

Hi , the code works,but there is a problm that when the word that I want to replace it is a part of another word"like 'the' in 'there,these,rather'"the letters of 'the' in these words also replaced ,I want only the word "the" to be replaced. I tried this code instead of strfind but also doesn't work >>idx = regexpi(A, 't[h]+e'); thanks for your efforts.

[Walter Roberson]

To go further, you need to define what a "word" is. In English that is not easy.

The below is an example I used in 2008 for someone wanting to separate out paragraphs. Which are the words in this?

Mr. Todd E. Jones gave $3000. (!) in nickels, dimes, etc. to his
No. 1 son at 4 7th Ave. N., NY. NY. USA., who exclaimed "What joy!
Now I can buy 3 lbs. of St. Tropiz bananas... or can I?!"