Structure Indexing to Find Words
7 visualizaciones (últimos 30 días)
Mostrar comentarios más antiguos
Russell Marki
el 20 de Mzo. de 2018
Comentada: Russell Marki
el 21 de Mzo. de 2018
clear
load('dict_perms.mat')
dict=6;
dict_perms=dict_perms{6};
dict_char=char(dict_perms+64);
dict_size=length(dict_perms(:,1));
for i=1:dict_size
dict_lex.(dict_char(i,1)).(dict_char(i,2)).(dict_char(i,3)).(dict_char(i,4)).(dict_char(i,5)).(dict_char(i,6))=uint16(i);
end
%the next letters possible from a series of letters can be found with
letters=fieldnames(dict_lex.('A').('B').('H'));
%I want words from possible letters
%like dict_lex.(['A','B']).(['D','B']).(['F','H']).(['O','F']).(['R','M']).(['S','K'])
%could be found with a for loop but it is too time consuming
fieldnames(dict_lex.('A'));
fieldnames(dict_lex.('B'));
I need to find all possible words that have letters in certain parts of the word. This could be done with a for loop but that is too time consuming. Can anyone point me in the right direction?
1 comentario
Stephen23
el 21 de Mzo. de 2018
"I need to find all possible words that have letters in certain parts of the word."
This is trivial with regular expressions. See my answer.
Respuesta aceptada
Stephen23
el 21 de Mzo. de 2018
Editada: Stephen23
el 21 de Mzo. de 2018
Dynamically accessing the fieldnames of nested structures is likely to be a very inefficient solution, and is far too complex for the task. You would be much better off simply accessing the data directly from the char array using logical indexing, or converting to a cell array of char vectors and then using standard, efficient built-in tools such as regular expressions, or even strncmp. For example:
>> DC = char(dict_perms{6}+64);
>> idx = DC(:,1)=='A' & DC(:,2)=='B' & DC(:,3)=='H';
>> DC(idx,:)
ans = ABHORS
To match multiple character you could add more logical conditions to the index:
>> idx = ...
(DC(:,1)=='A' | DC(:,1)=='B') & ...
(DC(:,2)=='B' | DC(:,2)=='D') & ...
(DC(:,3)=='H' | DC(:,3)=='F') & ...
(DC(:,4)=='O' | DC(:,4)=='F') & ...
(DC(:,5)=='R' | DC(:,5)=='M') & ...
(DC(:,6)=='S' | DC(:,6)=='K');
>> DC(idx,:)
ans = ABHORS
But actually it would be much easier and more versatile to use regular expressions:
>> DS = cellstr(DC);
>> idx = ~cellfun('isempty',regexp(DS,'^[AB][DB][FH][OF][RM][SK]','once'));
>> DC(idx,:)
ans = ABHORS
It is easy with regular expressions to return the complete matching words, the matching letters, their indices, or the trailing letters... it all depends on what you want. If you give a more accurate description of the data that you need then I can help you with the regular expression.
2 comentarios
Guillaume
el 21 de Mzo. de 2018
I agree with Stephen. This is exactly the sort of job regular expressions are designed for and it's unlikely you'll be able to write something more efficient. regular expression engines are highly optimised.
An alternative to storing the words as a 2d char array or a cell array of 1d char array would be to store them as a string array, which overall is a lot easier to manipulate. To convert the whole dict_perms in a cell array of string arrays:
dict_lex = cellfun(@(c) string(char(c+64)), dict_perms, 'UniformOutput', false)
Más respuestas (1)
KSSV
el 21 de Mzo. de 2018
T = table(dict_char) ;
T = table2cell(T) ;
idx = strfind(T,'A') ;
Read about strfind. If you convert your character array to cell, you can use certain functions and make the code run faster.
Ver también
Categorías
Más información sobre Structures en Help Center y File Exchange.
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!