I got a string array of the format
sLine =
{
[1,1] = 13-Jul-16,10.46,100.63,15.7,54.4,55656465
[1,2] = 12-Jul-16,10.47,100.64,15.7,54.4,55656465
[1,3] = 11-Jul-16,10.48,100.65,15.7,54.4,55656465
[1,4] = 10-Jul-16,10.49,100.66,15.7,54.4,55656465
}
In which each element is a string ("13-Jul-16,10.46,100.63,15.7,54.4,55656465" is a string).
I need to convert this to 6 vectors, something like
[a b c d e f] = ...
such a way, for example, for the 1st column, it would be
a = [13-Jul-16;12-Jul-16;11-Jul-16;10-Jul-16]
I tried to use cell2mat function, but for some reason it does not separate the fields into matrix elements, but it concatenates the whole string into something like
cell2mat(sLine)
ans =
13-Jul-16,10.46,100.63,15.7,54.4,5565646512-Jul-16,10.47,100.64,15.7,54.4,5565646511-Jul-16,10.48,100.65,15.7,54.4,5565646510-Jul-16,10.49,100.66,15.7,54.4,55656465
So, how can I solve this?
Update
I got the sLine matrix following the steps
pFile = urlread('http://www.google.com/finance/historical?q=BVMF:PETR4&num=365&output=csv');
sLine = strsplit(pFile,'\n');
sLine(:,1)=[];
Update
Thanks to #Suever I could get now the column dates. So the updated last version of the code is
pFile = urlread('http://www.google.com/finance/historical?q=BVMF:PETR4&num=365&output=csv');
pFile=strtrim(pFile);
sLine = strsplit(pFile,'\n');
sLine(:,1)=[];
split_values = regexp(sLine, ',', 'split');
values = cat(1, split_values{:});
values(:,1)
Your data is all strings, therefore you will need to do some string manipulation rather than using cell2mat.
You will want to split each element at the ,characters and then concatenate the result together.
sLine = {'13-Jul-16,10.46,100.63,15.7,54.4,55656465',
'12-Jul-16,10.47,100.64,15.7,54.4,55656465',
'11-Jul-16,10.48,100.65,15.7,54.4,55656465',
'10-Jul-16,10.49,100.66,15.7,54.4,55656465'};
split_values = cellfun(#(x)strsplit(x, ','), sLine, 'uniformoutput', 0);
values = cat(1, split_values{:});
values(:,1)
% {
% [1,1] = 13-Jul-16
% [2,1] = 12-Jul-16
% [3,1] = 11-Jul-16
% [4,1] = 10-Jul-16
% }
If you want it to be more concise, we can just use regexp to split it up instead of strsplit since it can accept a cell array as input.
split_values = regexp(sLine, ',', 'split');
values = cat(1, split_values{:});
Update
The issue with the code that you've posted is that there is a trailing newline in the input and when you split on newlines the last element of your sLine cell array is empty causing your issues. You'll want to use strtrim on pFile before creating the cell array to remove trailing newlines.
sLine = strsplit(strtrim(pFile), '\n');
sLine(:,1) = [];
Related
How to create a whole list of string from one string where each string in the list containing exactly one character replacement? The string itself is consisted of only four characters (say: A, B, C, and D), so that the whole list of a string of length n would contain 3n+1 strings with exactly one character replacement.
Example:
inputstr = 'ABCD'
output = ['ABCD', 'BBCD', 'CBCD', 'DBCD', 'AACD', 'ACCD', 'ADCD', 'ABAD', 'ABBD', 'ABDD', 'ABCA', 'ABCB', 'ABCC']
I write the following python code:
strin = 'ABCD'
strout = set()
tempstr1 = ''
tempstr2 = ''
tempstr3 = ''
tempstr4 = ''
for base in range(len(strin)):
if strin[base] == 'A': #this block will be repeated for char B, C and D
tempstr1 = strin.replace(strin[base], 'A')
strout.add(tempstr1)
tempstr1 = ''
tempstr2 = strin.replace(strin[base], 'B')
strout.add(tempstr2)
tempstr2 = ''
tempstr3 = strin.replace(strin[base], 'C')
strout.add(tempseq3)
tempstr3 = ''
tempstr4 = strin.replace(strin[base], 'D')
strout.add(tempseq4)
tempstr4 = ''
return strout
and it works well as long as there is no repeated character (such as 'ABCD'). However, when the input string contains repeated character (such as 'AACD'), it will return less than 3n+1 string. I tried with 'AACD' string and it returns only 10 instead of 13 strings.
Anyone can help?
change
strout = set() ===> strout = list()
I found it. I used a slicing method to create a list of total combination of strings with one replacement.
for i in range(len(seq)):
seqxlist.append(seq[:i] + 'x' + seq[i+1:])
and after that I filter out all the x-replaced strings which are longer than the original string length:
seqxlist = [x for x in seqxlist if (len(x) == len(seq))]
Then, I changed x into any of the substitution characters:
for m in seqxlist:
tempseq1 = m.replace('x', 'A')
outseq.append(tempseq1)
tempseq2 = m.replace('x', 'B')
outseq.append(tempseq2)
tempseq3 = m.replace('x', 'C')
outseq.append(tempseq3)
tempseq4 = m.replace('x', 'D')
outseq.append(tempseq4)
This will create all the possible combinations of string replacement, but still contains duplicates. To remove duplicates, I use set() to the outseq list.
How can I convert a matrix
A=[1,2,3;4,5,6]
to a cell of string
A_str = {'1_2_3';'4_5_6'};
One approach could be this -
%// Input
A=[1,2,3;4,5,6]
%// Make a cell array with each element a string off each element of A
cells = cellfun(#(x) num2str(x),num2cell(A),'Uni',0)
%// Join the cells with strjoin using `_` as the delimiter
A_str = arrayfun(#(n) strjoin(cells(n,:),'_'),1:size(cells,1),'Uni',0).'
Output -
A_str =
'1_2_3'
'4_5_6'
found this solution that seems faster
A=[1,2,3;4,5,6]
A_str = cell(size(A,1),1);
for index_row = 1 : size(A,1)
clear allOneString_temp
allOneString_temp = sprintf('%.0f_' , A(index_row,:));
A_str{index_row,:} = allOneString_temp(1:end-1);
end
Another approach, without loops:
A_str = num2str(A,'%i_');
A_str = mat2cell(A_str(:,1:end-1), ones(1,size(A_str,1)));
I have a string (eg. 'STA') and I want to make a cell array that will be a concatenation of my sting with a numbers from 1 to X.
I want the code to do something like the fore loop here below:
for i = 1:Num
a = [{a} {strcat('STA',num2str(i))}]
end
I want the end results to be in the form of {<1xNum cell>}
a = 'STA1' 'STA2' 'STA3' ...
(I want to set this to a uitable in the ColumnFormat array)
ColumnFormat = {{a},... % 1
'numeric',... % 2
'numeric'}; % 3
I'm not sure about starting with STA1, but this should get you a list that starts with STA (from which I guess you could remove the first entry).
N = 5;
[X{1:N+1}] = deal('STA');
a = genvarname(X);
a = a(2:end);
You can do it with combination of NUM2STR (converts numbers to strings), CELLSTR (converts strings to cell array), STRTRIM (removes extra spaces)and STRCAT (combines with another string) functions.
You need (:) to make sure the numeric vector is column.
x = 1:Num;
a = strcat( 'STA', strtrim( cellstr( num2str(x(:)) ) ) );
As an alternative for matrix with more dimensions I have this helper function:
function c = num2cellstr(xx, varargin)
%Converts matrix of numeric data to cell array of strings
c = cellfun(#(x) num2str(x,varargin{:}), num2cell(xx), 'UniformOutput', false);
Try this:
N = 10;
a = cell(1,N);
for i = 1:N
a(i) = {['STA',num2str(i)]};
end
I have a string stored in sqlite database and I've assigned it to a var, e.g. string
string = "First line and string. This should be another string in a new line"
I want to split this string into two separated strings, the dot (.) must be replace with (\n) new line char
At the moment I'm stuck and any help would be great!!
for row in db:nrows("SELECT * FROM contents WHERE section='accounts'") do
tabledata[int] = string.gsub(row.contentName, "%.", "\n")
int = int+1
end
I tried the other questions posted here in stachoverflow but with zero luck
What about this solution:`
s = "First line and string. This should be another string in a new line"
a,b=s:match"([^.]*).(.*)"
print(a)
print(b)
Are you looking to actually split the string into two different string objects? If so maybe this can help. It's a function I wrote to add some additional functionality to the standard string library. You can use it as-is or rename it to what ever you like.
--[[
string.split (s, p)
====================================================================
Splits the string [s] into substrings wherever pattern [p] occurs.
Returns: a table of substrings or, if no match is made [nil].
--]]
string.split = function(s, p)
local temp = {}
local index = 0
local last_index = string.len(s)
while true do
local i, e = string.find(s, p, index)
if i and e then
local next_index = e + 1
local word_bound = i - 1
table.insert(temp, string.sub(s, index, word_bound))
index = next_index
else
if index > 0 and index <= last_index then
table.insert(temp, string.sub(s, index, last_index))
elseif index == 0 then
temp = nil
end
break
end
end
return temp
end
Using it is very simple, it returns a tables of strings.
Lua 5.1.4 Copyright (C) 1994-2008 Lua.org, PUC-Rio
> s = "First line and string. This should be another string in a new line"
> t = string.split(s, "%.")
> print(table.concat(t, "\n"))
First line and string
This should be another string in a new line
> print(table.maxn(t))
2
I want to concatenate (padding with spaces) the strings in a cell array {'a', 'b'} to give a single string 'a b'. How can I do this in MATLAB?
You can cheat a bit, by using the cell array as a set of argument to the sprintf function, then cleaning up the extra spaces with strtrim:
strs = {'a', 'b', 'c'};
strs_spaces = sprintf('%s ' ,strs{:});
trimmed = strtrim(strs_spaces);
Dirty, but I like it...
matlab have a function to do this,
ref:
strjoin
http://www.mathworks.com/help/matlab/ref/strjoin.html
strjoin
Join strings in cell array into single string
Syntax
str = strjoin(C) example
str = strjoin(C,delimiter)
Ex:
Join List of Words with Whitespace
Join individual strings in a cell array of strings, C, with a single space.
C = {'one','two','three'};
str = strjoin(C)
str =
one two three
Small improvement (?) on the answer by Alex
strs = {'a','b','c'};
strs_spaces = [strs{1} sprintf(' %s', strs{2:end})];
You can accomplish this using the function STRCAT to append blanks to all but the last cell of your cell array and then concatenate all the strings together:
>> strCell = {'a' 'b' 'c' 'd' 'e'};
>> nCells = numel(strCell);
>> strCell(1:nCells-1) = strcat(strCell(1:nCells-1),{' '});
>> fullString = [strCell{:}]
fullString =
a b c d e
Both join and strjoin are introduced in R2013a. However, the mathworks site about strjoin reads:
Starting in R2016b, the join function is recommended to join elements of a string array.
>> C = {'one','two','three'};
>> join(C) %same result as: >> join(C, ' ')
ans =
string
"one two three"
>> join(C, ', and-ah ')
ans =
string
"one, and-ah two, and-ah three"
Personally I like Alex' solution as well, as older versions of Matlab are abundant in research groups around the world.