Morse Decoder with Character Counter

I'm trying to program a morse decoder, in which you enter morse code (letters separated by '/') which then counts the frequencies of each character in the output.

Here is where I've gotten stuck:

clear all, close all,

clc

userMorse = '-.-./---/...-/../-../.----/----./..--.- /.--./.-/-./-.././--/../-.-./..--.- /...-/.-/-.-./-.-./../-././';

code = {'.----','..---','...--','....-','.....','-....','--...','---..','----.','-----','.-',...

'-...','-.-.','-..','.','..-.','--.','....','..','.---','-.-','.-..','--','-.','---',...

'.--.','--.-','.-.','...','-','..-','...-','.--','-..-','-.--','--..', '..--.-'};

letter = {'1','2','3','4','5','6','7','8','9','0',...

'A','B','C','D','E','F','G','H','I','J','K','L',...

'M','N','O','P','Q','R','S','T','U','V','W','X',...

'Y','Z','-'};

codeTable = cell(2,37);

codeTable(1,:) = letter;

codeTable(2,:) = code;

splitUserMorse = strsplit(userMorse,'/');

for i = 1:length(splitUserMorse)

indexC = strfind(code,cell2mat(splitUserMorse(i)));

Index{1,i} = find(not(cellfun('isempty',indexC)));

end

Answer 1

[Drishan Poovaya]

Hi,

First of all, there are a few errors with your userMorse variable. Every time you have typed "..--.-", which indicates a '-' character, there is an additional space before the /. This will cause errors with string matching.

Another change needed is the last / at the end of the userMorse variable must be omitted, otherwise, the split function returns one blank element at the end.

You can see the code below, where I have made some changes. It should work now. In the end, I am saving your results in a table, as it would visually appear nicely

clear all, close all,
clc
userMorse = '-.-./---/...-/../-../.----/----./..--.-/.--./.-/-./-.././--/../-.-./..--.-/...-/.-/-.-./-.-./../-./.';
code = {'.----','..---','...--','....-','.....','-....','--...','---..','----.','-----','.-',...
    '-...','-.-.','-..','.','..-.','--.','....','..','.---','-.-','.-..','--','-.','---',...
    '.--.','--.-','.-.','...','-','..-','...-','.--','-..-','-.--','--..', '..--.-'};
letter = {'1','2','3','4','5','6','7','8','9','0',...
    'A','B','C','D','E','F','G','H','I','J','K','L',...
    'M','N','O','P','Q','R','S','T','U','V','W','X',...
    'Y','Z','-'};
splitUserMorse = strsplit(userMorse,'/');
indexC = zeros(1,length(splitUserMorse));

%Convert morse code to string
for i = 1:length(splitUserMorse)
    idx = find(strcmp(code,splitUserMorse{i}));
    indexC(i) = idx;       
end

s = letter(indexC);
freq = zeros(1,37);

%find frequency of each character in string
for i = 1:length(letter)
   freq(i) =   nnz(find(strcmp(s,letter{i})));
end

%SAve results in table
sz = [37 2];
varTypes = ["string","double"];
varNames = ["Letter","Frequency",];
tlb = table('Size',sz,'VariableTypes',varTypes,'VariableNames',varNames);
tlb(:,1) = letter';
tlb(:,2) = num2cell(freq)';