I have a 150X1 cell array. Within the array there are multiple data types. The first cell contains 0.9VA = 1.012207; the second: 0.9VA_CLK = 0.020752; and so on like this (for the most part). I would like to split the cell into two cells using the = as the delimiter. Thus, {1,1}: 0.9VA and {1,2}: 1.012207; {2,1}: 0.9VA_CLK and {2,2}: 0.020752; so on and so forth. I have tried converting them to strings and then using strsplit; however, I run into problems because the string arrays are variable in size.
If there is any other information that I can provide please let me know. Thank you for your help and time in advance.
You can indeed apply strsplit to each of the strings (char arrays) in the cell array. To do so, you can use cellfun:
c{1} = '0.9VA = 1.012207';
c{2} = '0.9VA_CLK = 0.020752';
c{3} = 'CSIPhgenSWoffList = [0, 0, 0, 0]';
c{4} = 'SomethingElse = [0.020752, 0.24564]';
c = cellfun(#(x)strsplit(x,'='),c,'UniformOutput',false);
c = cat(1,c{:});
I use a small example cell array c here, containing four strings, I hope this is representative. I apply strplit to each cell in c using cellfun(x,'='), which splits at the equal sign and returns a cell array with cell arrays. That is, each string in c is turned into a cell array with 2 strings (e.g. '0.9VA ' and ' 1.012207'. This does leave some spaces at the beginning and end of the strings.
The next line, cat, converts this cell array of cell arrays into a two-dimensional cell array. The final output is a cell array c containing the same number of rows as the original cell array, and with 2 columns. The first column corresponds to the part before the equal sign, the second column to the part after the equal sign.
To remove the spaces, you can use cellfun again, with strtrim:
c = cellfun(#strtrim,c,'UniformOutput',false);
Related
I am trying to grab data from an excel spread sheet and grab only the information from cells that match a string. Eg. if cell A10 contains the word 'Canada' it should return that cell.
I have tried using strcmp(https://www.mathworks.com/help/matlab/ref/strcmp.html) to check if string in argument 1 is contained in a cell array containing many strings, the second argument
[num,txt,raw] = xlsread('\\Client\C$\Users\Fish\Desktop\dataset\dataset.csv');
mytable = cell(raw);
for i = 1:54841
array_index = i;
string_index = mytable(i,2);
string_eastern = {'Canada', 'Ontario'};
if strcmp(string_index,string_eastern);
fprintf('%d\n',array_index)
end
end
In the above example if my string_eastern only contains one element, say 'Canada', it will return the index value of every instance of 'Canada'. If I add more elements I expect it would return index values for every instance where string_index would match with a string contained in string_eastern. However I get no results at all if I add more elements.
Pretty much I wanted to check my string_index agaisnt string_eastern, if the values match then I want it to return that cell value. This works when string_eastern is only 1 element but does not work with more than 1.
To access cell contents, use the curly brackets {}. So if I wanted to access the first element of my cell, I would say this:
string = cell{1};
Read more on the MATLAB Documentation about cells to learn more and to answer any of your further questions.
I have a cell array with values similar to the following one
13:41:54.879
I would like to extract only 13:41 part of the given value and mitigate the rest. I tried various combinations of extractBefore() and extractAfter() but couldn't get it.
You can use a regular expression to match the pattern "digits, colon, digits":
c = {'13:41:54.879', '1:22:33.45679'};
result = regexp(c, '\d+:\d+', 'match', 'once');
gives
result =
1×2 cell array
{'13:41'} {'1:22'}
I have a 55X1 cell array. Each cell contains a 1X178 string array of numbers. I would like to convert all the cells to a double array, but in such a way that it forms a 55X178 double array.
Take, for example, the 55X1 cell array dataCellOut = {each cell has a 1X178 string}. I can use: na=str2num(dataCellOut{1}) and this will output a 1X178 double array. I have tried using: na=cellfun(#str2num, dataCellOut, 'UniformOutput', false) and this does not work (error: "input must be a character vector or string scalar"). I have worked on this for awhile to no avail.
I hope this makes sense and if there is anything else that I can offer please don't hesitate to let me know. Thank you in advance!
According to the documentation to str2num:
The str2num function does not convert cell arrays or nonscalar string arrays, and is sensitive to spacing around + and - operators. In addition, str2num uses the eval function, which can cause unintended side effects when the input includes a function name. To avoid these issues, use str2double.
str2double, however, does just as you want:
X = str2double(str) converts the text in str to double precision values. [...] str can be a character vector, a cell array of character vectors, or a string array. [...] If str is [...] a string array, then X is a numeric array that is the same size as str.
Thus, this should work:
na = cellfun(#str2double, dataCellOut, 'UniformOutput', false);
na = cat(1,na{:});
This simple statement works for me.
str2num(char(cellstr_array))
I have a cell data type matrix containing a header and a large number of rows.
sample data:
set press dp
32.7045 17.805965 123.75047
32.690094 17.80584 123.74992
32.6232 17.815094 123.790115
I am trying to find the index of a specific column using the strcmp command to search through the all the data.
dpCol = strcmp([data{:}], 'dp')
This always returns
dpCol =
0
Am I using the data cell type wrong or something? Thank you!
Try using cell notation to yield just the 1st row, EG:
data(1,:) = {'set','press','dp'}
instead of unpacking* the entire cell array since strcmp can operate on cell arrays.
>>> data = {'set' 'press' 'dp'
32.7045 17.805965 123.75047
32.690094 17.80584 123.74992
32.6232 17.815094 123.790115}
data =
'set' 'press' 'dp'
[32.7045] [17.8060] [123.7505]
[32.6901] [17.8058] [123.7499]
[32.6232] [17.8151] [123.7901]
>>> col_idx = strcmp(data(1,:),'dp')
col_idx=
0 0 1
Then return the dp using the logical indices and cell2mat...
>>> dp = cell2mat(data(2:end,col_idx))
dp =
123.7505
123.7499
123.7901
or unpack* and concatenate the comma separated list
>>> dp = [data{2:end,col_idx}]
dp =
123.7505 123.7499 123.7901
As an alternative try cell2struct.
>>> datastruct = cell2struct(data(2:end,:),data(1,:),2)
datastruct =
3x1 struct array with fields:
set
press
dp
Then dp is ...
>>> dp = [datastruct.dp]
dp =
123.7505 123.7499 123.7901
* Using the colon operator inside curly braces unpacks an cell array into a comma separated list. Using square brackets horizontally concatenates the comma separated list which returns a character array set pressdp{{{ since the first item in the list is a character array. The garbage characters between and after 'set', 'press' and 'dp' are caused by reading the doubles as char. IE: char(32.7045) is the ASCII equivalent of whitespace. The arrays always get unpacked as column.
I have a cell with value WORD = '00000'. But I just want to take the 4th and 5th value.
I already tried KATA=WORD(4:5),
I also tried KATA=WORD{4}
But still cannot.
I got this error message :
Index exceeds matrix dimensions.
How to split it? It's in <cell> type.
First you need to index the content of "first" (and only) cell element with curly brackets {} and then you can index the vector (). Therefore you need:
WORD = {'12345'}
output = WORD{1}(4:5)
which gives:
output =
45
You might have something like this
>> word = {'00000'};
This is a 1x1 cell array containing a 1x5 char array. To index into the char array, you first need to index into the cell array, which you do with
>> word{1}
ans =
00000
And now you can index the 4th and 5th element
>> word{1}(4:5)
ans =
00