Ok so I have retrieved this string from the text file now I am supposed to shift it by a specified amount. so for example, if the string I retrieved was
To be, or not to be
That is the question
and the shift number was 5 then the output should be
stionTo be, or not
to beThat is the que
I was going to use circshift but the given string wouldn't of a matching dimesions. Also the string i would retrieve would be from .txt file.
So here is the code i used
S = sprintf('To be, or not to be\nThat is the question')
circshift(S,5,2)
but the output is
stionTo be, or not to be
That is the que
but i need
stionTo be, or not
to beThat is the que
By storing the locations of the new lines, removing the new lines and adding them back in later we can achieve this. This code does rely on the insertAfter function which is only available in MATLAB 2016b and later.
S = sprintf('To be, or not to be\nThat is the \n question');
newline = regexp(S,'\n');
S(newline) = '';
S = circshift(S,5,2);
for ii = 1:numel(newline)
S = insertAfter(S,newline(ii)-numel(newline)+ii,'\n');
end
S = sprintf(S);
You can do this by performing a circular shift on the indices of the non-newline characters. (The code below actually skips all control characters with ASCII code < 32.)
function T = strshift(S, k)
T = S;
c = find(S >= ' '); % shift only printable characters (ascii code >= 32)
T(c) = T(circshift(c, k, 2));
end
Sample run:
>> S = sprintf('To be, or not to be\nThat is the question')
S = To be, or not to be
That is the question
>> r = strshift(S, 5)
r = stionTo be, or not
to beThat is the que
If you want to skip only the newline characters, just change to
c = find(S != 10);
Related
How can I go about doing this? So far I've opened the file like this
fileID = fopen('hamlet.txt'.'r');
[A,count] = fscanf(fileID, '%s');
fclose(fileID);
Getting spaces from the file
First, if you want to capture spaces, you'll need to change your format specifier. %s reads only non-whitespace characters.
>> fileID = fopen('space.txt','r');
>> A = fscanf(fileID, '%s');
>> fclose(fileID);
>> A
A = Thistexthasspacesinit.
Instead, we can use %c:
>> fileID = fopen('space.txt','r');
>> A = fscanf(fileID, '%c');
>> fclose(fileID);
>> A
A = This text has spaces in it.
Mapping between characters and values (array indices)
We could create a character array that contains all of the target characters to look for:
search_chars = ['A':'Z', 'a':'z', ',', '.', ' '];
That would work, but to map the character to a position in the array you'd have to do something like:
>> char_pos = find(search_chars == 'q')
char_pos = 43
You could also use containters.Map, but that seems like overkill.
Instead, let's use the ASCII value of each character. For convenience, we'll use only values 1:126 (0 is NUL, and 127 is DEL. We should never encounter either of those.) Converting from characters to their ASCII code is easy:
>> c = 'q'
c = s
>> a = uint8(c) % MATLAB actually does this using double(). Seems wasteful to me.
a = 115
>> c2 = char(a)
c2 = s
Note that by doing this, you're counting characters that are not in your desired list like ! and *. If that's a problem, then use search_chars and figure out how you want to map from characters to indices.
Looping solution
The most intuitive way to count each character is a loop. For each character in A, find its ASCII code and increment the counter array at that index.
char_count = zeros(1, 126);
for current_char = A
c = uint8(current_char);
char_count(c) = char_count(c) + 1;
end
Now you've got an array of counts for each character with ASCII codes from 1 to 126. To find out how many instances of 's' there are, we can just use its ASCII code as an index:
>> char_count(115)
ans = 4
We can even use the character itself as an index:
>> char_count('s')
ans = 4
Vectorized solution
As you can see with that last example, MATLAB's weak typing makes characters and their ASCII codes pretty much equivalent. In fact:
>> 's' == 115
ans = 1
That means that we can use implicit broadcasting and == to create a logical 2D array where L(c,a) == 1 if character c in our string A has an ASCII code of a. Then we can get the count for each ASCII code by summing along the columns.
L = (A.' == [1:126]);
char_count = sum(L, 1);
A one-liner
Just for fun, I'll show one more way to do this: histcounts. This is meant to put values into bins, but as we said before, characters can be treated like values.
char_count = histcounts(uint8(A), 1:126);
There are dozens of other possibilities, for instance you could use the search_chars array and ismember(), but this should be a good starting point.
With [A,count] = fscanf(fileID, '%s'); you'll only count all string letters, doesn't matter which one. You can use regexp here which search for each letter you specify and will put it in a cell array. It consists of fields which contains the indices of your occuring letters. In the end you only sum the number of indices and you have the count for each letter:
fileID = fopen('hamlet.txt'.'r');
A = fscanf(fileID, '%s');
indexCellArray = regexp(A,{'A','B','C','D',... %I'm too lazy to add the other letters now^^
'a','b','c','d',...
','.' '};
letterCount = cellfun(#(x) numel(x),indexCellArray);
fclose(fileID);
Maybe you put the cell array in a struct where you can give fieldnames for the letters, otherwise you might loose track which count belongs to which number.
Maybe there's much easier solution, cause this one is kind of exhausting to put all the letters in the regexp but it works.
When I save a table as PDF (using report generator) I do not get the numeric fields (Index1, Index2, Index3) shortG format (total of 5 digits). What is the problem and how can I fix it?
The code:
function ButtonPushed(app, event)
import mlreportgen.dom.*;
import mlreportgen.report.*
format shortG;
ID = [1;2;3;4;5];
Name = {'San';'John';'Lee';'Boo';'Jay'};
Index1 = [71.1252;69.2343245;64.345345;67.345322;64.235235];
Index2 = [176.23423;163.123423654;131.45364572;133.5789435;119.63575647];
Index3 = [176.234;16.123423654;31.45364572;33.5789435;11.6647];
mt = table(ID,Name,Index1,Index2,Index3);
d = Document('myPDF','pdf');
d.OutputPath = ['E:/','temp'];
append(d,'Table 1: ');
append(d,mt);
close(d);
rptview(d.OutputPath);
end
To fix it, format your numeric arrays to character arrays with 5 significant digits before writing to PDF.
mt = table(ID,Name,f(Index1),f(Index2),f(Index3));
where,
function FivDigsStr = f(x)
%formatting to character array with 5 significant digits and then splitting.
%at each tab. categorical is needed to remove ' 's that appear around char
%in the output PDF file with newer MATLAB versions
%e.g. with R2018a, there are no ' ' in the output file but ' ' appears with R2020a
FivDigsStr = categorical(split(sprintf('%0.5G\t',x)));
%Removing the last (<undefined>) value (which is included due to \t)
FivDigsStr = FivDigsStr(1:end-1);
end
The above change gives the following result:
Edit:
To bring back the headers:
mt.Properties.VariableNames(3:end) = {'Index1', 'Index2', 'Index3'};
or in a more general way to extract the variable names instead of hardcoding them, you can use inputnames to extract the variable names.
V = #(x) inputname(1);
mt.Properties.VariableNames(3:end) = {V(Index1), V(Index2), V(Index3)};
which gives:
So I'm trying to work with some data files that contain a text header followed by binary data, 16 bits signed integers with the least significant byte first.
I can't seem to open the binary data correctly. The text header is of variable length.
I've tried the following, but my problem is that the data is not actually stored as binary, but is already a number, but not correctly.
The header is of variable length so I can't tell it to read after so many characters without first opening the file.
fileName = 'PATH/TO/FILE/FILE_NAME.DAT';
dataFile = fopen(fileName);
header = '';
i = 1;
%dataContents = fileread(fileName);
dataContents = fread(dataFile);
while i < 115
char = dataContents(i);
header = [header char];
if char == '}'
break
end
i = i + 1;
end
header = header(2:end-1);
headerSplit = strsplit(header,',');
fileSize = str2double(headerSplit(17));
binaryData = dataContents(i:end);
data = [];
j = 1;
num = binaryData(1:50)
while j < fileSize
data = [data, bin2dec(num2str(binaryData(j:j+1)))];
j = j + 2;
end
length(data)
Any help would be great. I'm new to matlab so I'm probably missing something simple.
Without knowing the data format, it's nearly impossible to give a detailed advice. You probably need to set the precision argument of fread according to your data format.
After parsing your header, you know where your data begins. Use fseek(dataFile, numel(header)+2, 'bof') to set your file handle to the position where the file begins. Then start reading again using fread with a matching precision.
eliminate punctuation
words split when meeting new line and space, then store in array
check the text file got error or not with the function of checkSpelling.m file
sum up the total number of error in that article
no suggestion is assumed to be no error, then return -1
sum of error>20, return 1
sum of error<=20, return -1
I would like to check spelling error of certain paragraph, I face the problem to get rid of the punctuation. It may have problem to the other reason, it return me the error as below:
My data2 file is :
checkSpelling.m
function suggestion = checkSpelling(word)
h = actxserver('word.application');
h.Document.Add;
correct = h.CheckSpelling(word);
if correct
suggestion = []; %return empty if spelled correctly
else
%If incorrect and there are suggestions, return them in a cell array
if h.GetSpellingSuggestions(word).count > 0
count = h.GetSpellingSuggestions(word).count;
for i = 1:count
suggestion{i} = h.GetSpellingSuggestions(word).Item(i).get('name');
end
else
%If incorrect but there are no suggestions, return this:
suggestion = 'no suggestion';
end
end
%Quit Word to release the server
h.Quit
f19.m
for i = 1:1
data2=fopen(strcat('DATA\PRE-PROCESS_DATA\F19\',int2str(i),'.txt'),'r')
CharData = fread(data2, '*char')'; %read text file and store data in CharData
fclose(data2);
word_punctuation=regexprep(CharData,'[`~!##$%^&*()-_=+[{]}\|;:\''<,>.?/','')
word_newLine = regexp(word_punctuation, '\n', 'split')
word = regexp(word_newLine, ' ', 'split')
[sizeData b] = size(word)
suggestion = cellfun(#checkSpelling, word, 'UniformOutput', 0)
A19(i)=sum(~cellfun(#isempty,suggestion))
feature19(A19(i)>=20)=1
feature19(A19(i)<20)=-1
end
Substitute your regexprep call to
word_punctuation=regexprep(CharData,'\W','\n');
Here \W finds all non-alphanumeric characters (inclulding spaces) that get substituted with the newline.
Then
word = regexp(word_punctuation, '\n', 'split');
As you can see you don't need to split by space (see above). But you can remove the empty cells:
word(cellfun(#isempty,word)) = [];
Everything worked for me. However I have to say that you checkSpelling function is very slow. At every call it has to create an ActiveX server object, add new document, and delete the object after check is done. Consider rewriting the function to accept cell array of strings.
UPDATE
The only problem I see is removing the quote ' character (I'm, don't, etc). You can temporary substitute them with underscore (yes, it's considered alphanumeric) or any sequence of unused characters. Or you can use list of all non-alphanumeric characters to be remove in square brackets instead of \W.
UPDATE 2
Another solution to the 1st UPDATE:
word_punctuation=regexprep(CharData,'[^A-Za-z0-9''_]','\n');
I have a text file that looks like this:
(a (bee (cold down)))
if I load it using
c=textscan(fid,'%s');
I get this:
'(a'
'(bee'
'(cold'
'down)))'
What I would like to get is:
'('
'a'
'('
'bee'
'('
'cold'
'down'
')'
')'
')'
I know I can delimit with '(' and ')' by specifying 'Delimiter' in textscan, but then I will loose this character, which I want to keep.
Thank you in Advance.
The %s specifier indicates that you want Strings, what you want is individual chars. Use %c instead .
c=textscan(fid,'%c');
Update if you want too keep your words intact then you'll want to load your text using the %s specifier. After the text is loaded you can either solve this problem with Regular Expressions (not my forte) or write your own parser then parses each word individually and saves the paranthesis and words to a new cell array.
AFAIK, there is no canned routine capable of preserving arbitrary delimiters.
You'd have to do it yourself:
string = '(a (bee (cold down)))';
bo = string == '(';
bc = string == ')';
sp = string == ' ';
output = cell(nnz(bo|bc|sp)+1,1);
j = 1;
for ii = 1:numel(string)
if bo(ii)
output{j} = '(';
j = j + 1;
elseif bc(ii)
output{j} = ')';
j = j + 1;
elseif sp(ii)
j = j + 1;
else
output{j} = [output{j} string(ii)];
end
end
Which can probably be improved -- the growing character array will prevent the loop from being JIT'ed. The array bc | bo | sp holds all the information to vectorize this thing, I just don't see how at this hour...
Nevertheless, it should give you a place to start.
Matlab has a strtok function similar to C. Its format is:
token = strtok(str)
token = strtok(str, delimiter)
[token, remain] = strtok('str', ...)
there is also a string replace function strrep:
modifiedStr = strrep(origStr, oldSubstr, newSubstr)
What I would do is modify the original string with strrep to add in delimiters, then use strtok. Since you already scanned the string into c:
c = (c,'(','( '); %Add a space after each open paren
c = (c,')',' ) '); % Add a space before and after each close paren
token = zeros(10); preallocate for speed
i = 2;
[token(1), remain] = strtok(c, ' ');
while(remain)
[token(i), remain] = strtok(c, ' ');
i =i + 1;
end
gives you the linear token array of each of the string you requested.
strtok reference: http://www.mathworks.com/help/techdoc/ref/strtok.html
strrep reference: http://www.mathworks.com/help/techdoc/ref/strrep.html