How do I find specific values in a .txt file?

Hello everybody,

I have a .txt file. And I need to find the key words in the text then pick the value next to the key words. Here is one part of this text file:

%% Define the target filter
freq_step = 0.2;	% Frequency step (GHz)
lowest_freq = 20;	% Lowest frequency of the whole frequency band (GHz)
mid_freq = 33;	% Middle frequency of the passband (GHz)
highest_freq = 45;	% Highest frequency of the whole frequency band (GHz)
pass_s11_max_tgt = -10;	% Target maximum S11 in the passband (dB)
pass_s11_min_tgt = -15;	% Target minimum S11 in the passband (dB)
pass_s21_tgt = -1;	% Target S21 in the passband (dB)
stop_s11_tgt = -1;	% Target S11 in the stopband (dB)
stop_s21_max_tgt = -15;	% Target maximum S21 in the stopband (dB)
stop_s21_min_tgt = -25;	% Target minimum S21 in the stopband (dB)

I need the values after "freq_step = ", "lowest_freq = ", "highest_freq = ". Could anyone help me with that?

Answer 1

[Mathieu NOE]

hello

this code will extract the searched items and stote them in a table (taht you can save to excel if needed)

hope it helps

lines = readlines('Document1.txt');

for ci =1:numel(lines)
    line_str =  extractBefore(lines(ci),'='); % extract question number (with double quote)
    
    if strfind(line_str,'freq_step')
        Value1 =  str2num(extractBetween(lines(ci),'=',';')); % extract values and convert string to numerical
        
    elseif strfind(line_str,'lowest_freq')
        Value2 =  str2num(extractBetween(lines(ci),'=',';')); % extract values and convert string to numerical
        
    elseif strfind(line_str,'highest_freq')
        Value3 =  str2num(extractBetween(lines(ci),'=',';')); % extract values and convert string to numerical
   
    end

end

A = [Value1' Value2' Value3'];

T = array2table(A,    'VariableNames',{'freq step','lowest freq','highest freq'})

writetable(T,'test.xlsx')

[Ryan]

Amazing! It works!

You helped me a lot! And I learn a lot from it!

Thanks sincerely!

[Mathieu NOE]

you're welcome