MATLAB: How to get rid of “Error: Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.”

errorMATLABmorse

I am attempting to decode morse and the input "decode(—–)" gives me "Error: Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.". Can someone tell me why?

clear all; close all; 
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";"-"];
%userInput = input("Enter your morse code ");
function message = decode(morseCode)
numcharacters = count(morseCode, "/")
for i = 1:length(numcharacters)
    if ismember (morseCode(i), letter)
        disp(letter(i))
    end  
end
end

Best Answer

userInput = input("Enter your morse code ", 's');

Related Solutions

MATLAB: Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.

Remove the numbers before you commands.

Check that your parentheses are lining up the way you intend. Your first plot command has a mismatched number of opening and closing parentheses. Syntax should be plot(x,y)

plot(V_X(1,:)),((V_X(2,:)),'k')
             ^  ^ remove these ones

You use a lot of unnecessary parentheses. Removing these makes it easier to spot mismatches.

figure
plot(V_X(1,:),V_X(2,:),'k')
hold on 
title('--------',int2str(n))
plot(matrixV(1,:),matrixV(2,:),'--r*')
hold off

MATLAB: Find exact pattern in string

Your code is expecting userInput(i) to be an entire group of pulses. But it is not. userInput is a character vector and (i) is indexing individual characters.

You have three choices:

1. remove the 's' option from input() and require that the user enter in the form

["..-","-"]

with your program crashing if they make a mistake; or

1b) same but put in a try/catch to handle the inevitable errors more smoothly; or

2. Leave in the 's' but expect the user to use the above form but scan the character vector to ensure that it has the right format, and use eval() on the validated character vector;

3. Leave in the 's' and continue to expect the user to use / to mark the end of blocks, and split the character vector into pieces at each / and string() the cell array of character vectors you got from the splitting to create the string array that you can use (i) indexing with.

Best Answer

Related Solutions

MATLAB: Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.

MATLAB: Find exact pattern in string

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