Logical Test on Matrix Failing

I am having some difficulties with this function. For some reason the logical test:

little_endian_message(a) == 1

Doesn't work. Neither logical test works. But Matlab is able to return the correct element "little_endian_message(a)". Does anyone have any suggestions how I might fix this?

function [] = Generate_KC_Standard_Data( text_message )
 %UNTITLED Summary of this function goes here
 %   Detailed explanation goes here
 sample_rateHz  = 44100;

f_low  = 1200;

if true
  % code
end
f_high = 2400;

w_low  = (2*pi*f_low);
w_high = (2*pi*f_high);

low_sample_duration  = (4/ f_low);
high_sample_duration = (8/ f_high);

low_sample_times  = [0:(1/sample_rateHz):low_sample_duration];
high_sample_times = [0:(1/sample_rateHz):high_sample_duration];

low_tone  = 120*sin(w_low*low_sample_times);
high_tone = 120*sin(w_high*high_sample_times);
sample_size = numel(low_tone);

binary_message = (dec2bin(text_message))';
(binary_message(:) - '0');
little_endian_message = flip( binary_message, 1 );
[row_size, column_size] = size(binary_message);
length = numel( little_endian_message );

sound_output = zeros( length, sample_size );
for a = 1:numel(little_endian_message)
    if( little_endian_message(a) == 0 )
        sound_output(a,:) = low_tone;
    elseif(little_endian_message(a) == 1)
        sound_output(a,:) = high_tone;
    end
end
little_endian_message
numel(high_tone)
end

Answer 1

[Andrew Newell]

The variable little_endian_message is a char representation of binary numbers. Try this:

    if( little_endian_message(a) == '0' )
        sound_output(a,:) = low_tone;
    elseif(little_endian_message(a) == '1')
        sound_output(a,:) = high_tone;
    end