I got a code similar to this:
fprintf('Give a vector: \n')
fprintf('1. Vector/Matrix: X = {')
FirstVector = input('','s');
fprintf('}')
fprintf('\n')
It should print out something like this:
Give a vector:
1. Vector/Matrix: X = {UserInput}
Instead I get this:
Give a vector:
1. Vector/Matrix: X = {UserInput
}
The input-function is making a \n. How can I avoid that? The documentation of input is of no use, it doesn't even tell that input behaves that way.
You can get around this inherent limitation of input by adding a backspace character to the fprintf after the input. You can also condense your code into two lines, like so:
FirstVector = input('Give a vector: \n1. Vector/Matrix: X = {', 's');
fprintf([char(8) '}\n']);
Entering a 1:
Give a vector:
1. Vector/Matrix: X = {1}
Note also that the 's' option is for capturing character/string input. If you want the user to enter numeric values, leave that out.
Related
I'm having trouble figuring out how to count the occurrences of a character in a string within a cell. For example, I have a file that contains information like so:
type
m
mmNs
SmNm
and I'm trying to determine how many m's are in each line. To do this, I've tried this code:
sampleddata = dataset('file','sample.txt','Delimiter','\t');
muts = sampleddata.type;
fileID = fopen('number_occur.txt','w');
for j = 1:3
mutations = muts(j)
M = length(find(mutations == 'm'));
fprintf(fileID, '%1f\n',M)
end
fclose(fileID)
However, I get an error that informs me: "Undefined operator '==' for input arguments of type 'cell'." Does anyone know how to overcome this problem?
Gonna post a result here in case you did not find a way to do it. There are loads of ways to do it, I am just going to put one of them.
Basically, you want a regex to do string matches:
a = {'type';
'm';
'mmNs';
'SmNm';
'mmmmM'} %//Load in Data,
pattern = 'm'; %//The pattern you are looking for is 'm', it could be anything really, a number of specific word or a specific pattern
lines = regexp(a, pattern, 'tokens'); %// look for this pattern in each line
result = cellfun('length',lines); %//count the size of matched patterns, so each time it matches, the size should increase by 1.
This gives the result in a matrix form:
result =
0
1
2
2
4
I have to write a function to replace the characters of a string with those letters.
A=U
T=A
G=C
C=G
Example:
Input: 'ATAGTACCGGTTA'
Therefore, the output should be:
'UAUCAUGGCCAAU'
I can replace only one character. However, I have no how to do several. I could replace several if '"G=C and C=G" this condition was not there.
I use:
in='ATAGTACCGGTTA'
check=in=='A'
in(check)='U'
ans='UTUGTUCCGGTTU'
if I keep doing this at some point G will be replaced by C then then all the C will be replaced by G. How can I stop this?? Any help will be appreciated.
Just for fun, here's probably the absolute simplest way, via indexing:
key = 'UGCA';
[~, ~, idx] = unique(in);
out = key(idx'); % transpose idx since unique() returns a column vector
I do love indexing :D
Edit: As rightly pointed out, this is very optimised for the question as stated. Since [a, ~, idx] = unique(in); returns a and idx such that a(idx) == in, and by default a is sorted, we can just assume that a == 'ACGT' and pre-construct key to be the appropriate translation of indices into a.
If some characters from the known alphabet never appear in the input string, or if other unknown characters appear, then the indices don't match and the assumption breaks. In that case, we have to calculate the appropriate key explicitly - filling in the step that was optimised out above:
alph = 'ACGT';
trans = 'UGCA';
[key, ~, idx] = unique(in);
[~, alphidx, keyidx] = intersect(alph, key); % find which elements of alph
% appear at which points in key
key(keyidx) = trans(alphidx); % translate the elements of key that we can
out = key(idx');
The simplest way would be to use an intermediary letter. For instance:
in='ATAGTACCGGTTA'
in(in == 'A')='U'
in(in == 'T')='A'
in(in == 'C')='X'
in(in == 'G')='C'
in(in == 'X')='G'
This way you keep the 'C' and 'G' characters separate.
EDIT:
As others have mentioned, there are a few things other things you could do to improve this approach (though personally I think Notlikethat's way is cleanest). For instance, if you use a second variable, you don't have to worry about keeping 'C' and 'G' separate:
in='ATAGTACCGGTTA'
out=in;
out(in == 'A')='U';
out(in == 'T')='A';
out(in == 'C')='G';
out(in == 'G')='C';
Alternatively, you could make your indices first, then index after:
in='ATAGTACCGGTTA'
inA=in=='A';
inT=in=='T';
inC=in=='C';
inG=in=='G';
in(inA)='U';
in(inT)='A';
in(inC)='G';
in(inG)='C';
Finally, my personal favourite for sheer idiocy:
out=char(in+floor((68-in).*(in<70)*7/4)*4-round(ceil((in-67)/4)*3.7));
(Seriously, that last one works)
You can perform multiple character translation with bsxfun.
Inputs:
in = 'ATAGTACCGGTTA';
pat = ['A','T','G','C'];
subst = ['U','A','C','G'];
out0 ='UAUCAUGGCCAAU';
Translate all characters simultaneously:
>> ii = (1:numel(pat))*bsxfun(#eq,in,pat.'); %' instead of repmat and .*
>> out = subst(ii)
out =
UAUCAUGGCCAAU
>> isequal(out,out0)
ans =
1
Say you only want to translate a subset of the characters, leaving part of the sequence intact, it is easily solved with logical indexing and a few extra lines:
% Leave the Gs and Cs in place
pat = ['A','T'];
subst = ['U','A'];
ii = (1:numel(pat))*bsxfun(#eq,in,pat.'); %' same
out = char(zeros(1,numel(in)));
nz = ii>0;
out(nz) = subst(ii(nz));
out(~nz) = in(~nz)
out =
UAUGAUCCGGAAU
The original Gs and Cs are unchanged; A became U, and T became A (T is gone).
I would suggest to use containter.Map:
m=containers.Map({'A','T','G','C'},{'U','A','C','G'})
mapfkt=#(input)(cell2mat(m.values(num2cell(input))))
Usage:
mapfkt('ATAGTACCGGTTA')
Here is another method that should be fairly efficient, general, and in the line of thought of your original attempt:
%Suppose this is your input
myString = 'abcdeabcde';
fromSting = 'ace';
toString = 'xyz';
%Then it just takes this:
[idx fromLocation] = ismember(myString,fromSting)
myString(idx)=toString(fromLocation(idx))
If you know that all letters need to be replaced, the last line can be slightly simplified as you wont need to use idx.
Suppose I have a function that is something like this:
function [ c ] = input_args(m)
for i = 1 : m+1
c{i} = inputdlg('Enter next m value');
end
end
Now I'd like to change this so that the instruction to the user at the i'th stage of the for loop says something like "Enter the i'th m value", where i is the changing index in the for loop. How can I do this?
Thanks!
A string is a array of characters, so you can concatenate them like any other array. You need to use num2str to convert a number into a printable character.
inputdlg(['Enter the ' num2str(i) 'th m value']);
A more general solution would be to use sprintf to format your string; to do the same thing with sprintf you would use:
inputdlg(sprintf('Enter the %dth m value', i));
which you might find more readable (and allows you to use standard fprintf formatting options).
Say I had a variable called "x" and x=5.
I would like to do:
disp('x is equal to ' + x +'.');
and have that code print:
x is equal to 5.
This is how I am used to doing things in Java, so their must be a similar way to do this in MATLAB.
Thanks
If you want to use disp, you can construct the string to display like so:
disp(['x is equal to ',num2str(x),'.'])
I personally prefer to use fprintf, which would use the following syntax (and gives me some control over formatting of the value of x)
fprintf('x is equal to %6.2f.\n',x);
You can, of course, also supply x as string, and get the same output as disp (give or take a few line breaks).
fprintf('x is equal to %s\n',num2str(x))
printing out a few scalar variables in matlab is a mess (see answer above). having a function like this in your search path helps:
function echo(varargin)
str = '';
for k=1:length(varargin)
str = [str ' ' num2str(varargin{k})];
end
disp(str)
just nest a sprintf() inside the disp().
disp(sprintf("X is equal to %d.",x));
Using Matlab, write a function called tripFlip that takes in one string and switches each even-indexed charactar with the odd-indexed character immediately preceding it. Use iteration. Example: tripFlip('orange') ->'ronaeg'
I assume this is homework, so I won't give a complete answer. You can use double to convert a string to an array, and char to go back, if working with arrays makes the problem any easier. Otherwise, strings seem to work just like arrays in terms of indexing: s(1) gets the first character, length(s) gets the length, etc.
I agree its a homework question, and posting it here will only bite you back in the long run. But here goes:
a = 'orange';
b = '';
b(2:2:length(a))= a(1:2:end);
b(1:2:length(a))= a(2:2:end);
disp(b)
In one line:
>> input = 'orange';
>> output = input(reshape([2:2:end;1:2:end],1,[]))
output =
ronaeg
It's not a function and doesn't use iteration, but it's how you'd solve this if you were to learn Matlab.
Something like this should do the trick, perhaps you want to make it a bit more robust.
function b = TripFlip(a)
a = 'orange';
b = '';
for i = 2:2:length(a)
b=[b a(i) a(i-1)]
end