how can I read in this file of varying data types

I need to read in the year, magnitude, and location (city and state) from this file and the print it back out. I am running into issues in the second line because of New Madrid, MO.

.txt file:

January 7, 2016 4.8 Fairview, OK

February 7, 1812 7.5 New Madrid, MO

February 10, 2016 2.8 Avenal, CA

August 23, 2011 5.8 Mineral, VA

fid = fopen('earthquake_data.txt','r');
fprintf('Year\t\tMoment Magnitude\t\tLocation\t\tMercalli Intensity\n');
 
for i = 1:4
    
    yearis = fscanf(fid,'%*s%*s%f',1);
    mag = fscanf(fid,'%f',1);
    townis = fscanf(fid,'%*s%s',1);
    stateis = fscanf(fid,'%s',1);
 
    intensity = 0;
    if mag < 2
        intensity = '1';
    elseif mag < 3
        intensity = '1-2';
    elseif mag < 4
        intensity = '2-4';
    elseif mag < 5
        intensity = '4-6';
    elseif mag < 6
        intensity = '6-8';
    elseif mag < 7
        intensity = '7-10';
    else 
        intensity = '>8';
    end
 
fprintf('%d\t\t %.2f \t\t\t%s \t\t%s\n',yearis,mag,townis,intensity)
end

[dpb]

The problem is a poorly-constructed file that contains records with embedded blanks but is written as '%q' "quoted" string.

First option would be to fix the generator for the input file.

Failing that, would have to read each record in its entirety and parse by context to separate the various pieces.

Answer 1

[Jan]

One way - old-fashioned without textscan:

% UNTESTED!!! Written in the forum's interface without testing
[fid, msg] = fopen('earthquake_data.txt', 'r');
if fid == -1
    error('Cannot open file: %s', msg);
end
fprintf('Year\t\tMoment Magnitude\t\tLocation\t\tMercalli Intensity\n');

IntensityValue = [0,   3,     4,     5,     6,     7,      Inf];
IntensityList  = {'1', '1-2', '2-4', '4-6', '6-8', '7-10', '>8'};

while ~feof(fid)
    S = fgetl(fid);
    if ~ischar(S) || isempty(S) % Care about trailing new line
        continue;
    end
    C = strtrim(strsplit(S, ','));
    [Num, n] = sscanf(C{2}, '%d %g');
    Year     = Num(1);
    Mag      = Num(2);
    Town     = strtrim(C{2}(n+1:end));
    State    = C{3};
    
    index     = discretize(Mag, IntensityValue);
    Intensity = IntensityList{index};
    
    fprintf('%d\t\t %.2f \t\t\t%s \t\t%s\n', Year, Mag, Town, Intensity);
end
fclose(fid);

Answer 2

[Akira Agata]

Another possible solution:

fid = fopen('earthquake_data.txt','r');
s = textscan(fid,'%s','Delimiter','\n');
s = s{1};
fclose(fid);

s = regexprep(s,'(?<=[0-9]) ',',');
s = split(s,',');

Year = str2double(s(:,2));
Mag = str2double(s(:,3));
Town = s(:,4);

Intensity = cell(size(Mag));
Intensity(Mag<2) = {'1'};
Intensity(Mag<3) = {'1-2'};
Intensity(Mag<4) = {'2-4'};
Intensity(Mag<5) = {'4-6'};
Intensity(Mag<6) = {'6-8'};
Intensity(Mag<7) = {'7-10'};
Intensity(Mag>=7) = {'>8'};

Result = table(Year,Mag,Town,Intensity);

The result is as follows:

>> Result

Result =

4×4 table

Year Mag Town Intensity

____ ___ ____________ _________

2016 4.8 'Fairview' '7-10'

1812 7.5 'New Madrid' '>8'

2016 2.8 'Avenal' '7-10'

2011 5.8 'Mineral' '7-10'