I have field name which contains (.) for matlab structure
When I create structure, it throws invalid field name error
e.g
fieldName = 'Freq.01'
Structure
s.(fieldName) = 25;
As pointed out in Yuans's comment, fieldnames must not contain '.'. This may be the case because the Value of a field can be another field. Maybe you want to replace the '.' with '_' and then use your new valid fieldname:
fieldname = 'Freq.01';
fieldname = strrep(fieldname, '.', '_');
s.(fieldname) = 25
s.('hello').('world') = 17
You can use matlab.lang.makeValidName to convert an invalid name such as 'Freq.01' into something that is a valid name. (This is only available in relatively recent versions of MATLAB).
In older versions of MATLAB, you can use genvarname.
Related
I am trying to write a script that will auto sort files based on the 7th and 8th digit in their name. I get the following error: "Argument must be a string scalar or character vector". Error is coming from line 16:
Argument must be a string scalar or character vector.
Error in sort_files (line 16)
movefile (filelist(i), DirOut)
Here's the code:
DirIn = 'C:\Folder\Experiment' %set incoming directory
DirOut = 'C:\Folder\Experiment\1'
eval(['filelist=dir(''' DirIn '/*.wav'')']) %get file list
for i = 1:length(filelist);
Filename = filelist(i).name
name = strsplit(Filename, '_');
newStr = extractBetween(name,7,8);
if strcmp(newStr,'01')
movefile (filelist(i), DirOut)
end
end
Also, I am trying to make the file folder conditional so that if the 10-11 digits are 02 the file goes to DirOut/02 etc.
First, try avoid using the eval function, it is pretty much dreaded as slow and hard to understand. Specially if you need to create variables. Instead do this:
filelist = dir(fullfile(DirIn,'*.wav'));
Second, the passage:
name = strsplit(Filename, '_');
Makes name a list, so you can access name{1} or possibly name{2}. Each of these are strings. But name isn't a string, it is a list. extractBetween requires a string as an input. That is why you are getting this problem. But note that you could have simply done:
newStr = name(7:8);
If name was a string, which in Matlab is a char array.
EDIT:
Since it has been now claimed that the error occurs on movefile (filelist(i), DirOut), the likely cause is because filelist(i) is a struct. Wheres a filena name (char array) should have been given at input. The solution should be replacing this line with:
movefile(fullfile(filelist(i).folder, filelist(i).name), DirOut)
Now, if you want to number the output folders too, you can do this:
movefile(fullfile(filelist(i).folder, filelist(i).name), [DirOut,filesep,name(7:8)])
This will move a file to /DirOut/01. If you wanted /DirOut/1, you could do this:
movefile(fullfile(filelist(i).folder, filelist(i).name), [DirOut,filesep,int2str(str2num(name(7:8)))])
If my database contains entries with the following string values for the "key" field:
"a,b,c"
"a,b,z"
"a,b,c,d,e,f,z"
"d,e,f,g"
"d,e,f,g,z"
"h,i"
And I have a string like this:
"a,b,c,d,e,f,g,h"
How do I find the entries where the value of the key field matches the start of my string? E.g. I want to find the entry where the value of the key field is "a,b,c".
How do I find the entries where the value of the key field matches any part of my string? E.g. I want to find the entries where the value of the key field is "a,b,c" and "d,e,f,g".
To give some context in case anyone thinks this is a pointless task, I want to do stack matching. I will have entries in a database that identify bugs by the first N frames of the stack and then I want to identify bug(s) by the stack obtained from a core dump.
The answer is to use the $where operator. An example in Python, where search_string is the string we want to find matches with, is:
search_string = 'a,b,c,d,e,f,g,h'
js_check = 'function () { var search_string=\'' + search_string + '\'; return search_string.indexOf(this.key) >= 0; }'
matches = my_collection.find({'$where': js_check})
My input strings are
inputData = "99998UNKNOWN"
inputData = "01000AMEBACIDE/TRICHOM/ANTIBAC 1"
inputData = "34343AMEBACIDE/TRICHOM/ANTIBACSADWA1"
ID = inputData.Substring(0,5);
Name = inputData.Substring(5,30);
Level = inputData.Substring(35,1);
I am getting the below error,
Index and length must refer to a location within the string.
I can understand , the error is due to the length that specified in substring for "Name" is not matching with first input.
Is there any way to handle this issue with any input length?
One approach is to add a "sentinel" suffix to the end of the string before taking substrings. Now you can add it to the data string before taking substrings from it. As long as the suffix has sufficient length, you would never get an index/length exception:
var padded = inputData.PadRight(32);
ID = padded.Substring(0, 5).Trim();
Name = padded.Substring(5, 30).Trim();
Level = padded.Substring(30, 1).Trim();
However, now your code should check if ID, Name, or Level is empty.
I have file names stored as follows:
>> allFiles.name
ans =
k-120_knt-500_threshold-0.3_percent-34.57.csv
ans =
k-216_knt-22625_threshold-0.3_percent-33.33.csv
I wish to extract the 4 values from them and store in a cell.
data={};
for k =1:numel(allFiles)
data{k,1}=csvread(allFiles(k).name,1,0);
data{k,2}= %kvalue
data{k,3}= %kntvalue
data{k,4}=%threshold
data{k,5}=%percent
...
end
There's probably a regular expression that can be used to do this, but a simple piece of code would be
data={numel(allFiles),5};
for k =1:numel(allFiles)
data{k,1}=csvread(allFiles(k).name,1,0);
[~,name] = fileparts(allFiles(k).name);
dashIdx = strfind(name,'-'); % find location of dashes
usIdx = strfind(name,'_'); % find location of underscores
data{k,2}= str2double(name(dashIdx(1)+1:usIdx(1)-1)); %kvalue
data{k,3}= str2double(name(dashIdx(2)+1:usIdx(2)-1)); %kntvalue
data{k,4}= str2double(name(dashIdx(3)+1:usIdx(3)-1)); %threshold
data{k,5}= str2double(name(dashIdx(4)+1:end)); %percent
...
end
For efficiency, you might consider using a single matrix to store all the numeric data, and/or a structure (so that you can access the data by name rather than index).
You simply need to tokenize using strtok multiple times (there is more than 1 way to solve this). Someone has a handy matlab script somewhere on the web to tokenize strings into a cell array.
(1) Starting with:
filename = 'k-216_knt-22625_threshold-0.3_percent-33.33.csv'
Use strfind to prune out the extension
r = strfind(filename, '.csv')
filenameWithoutExtension = filename(1:r-1)
This leaves us with:
'k-216_knt-22625_threshold-0.3_percent-33.33'
(2) Then tokenize this:
'k-216_knt-22625_threshold-0.3_percent-33.33'
using '_' . You get the tokens:
'k-216'
'knt-22625'
'threshold-0.3'
'percent-33.33'
(3) Lastly, for each string, tokenize using using '-'. Each second string will be:
'216'
'22625'
'0.3'
'33.33'
And use str2num to convert.
Strategy: strsplit() + str2num().
data={};
for k =1:numel(allFiles)
data{k,1}=csvread(allFiles(k).name,1,0);
words = strsplit( allFiles(k).name(1:(end-4)), '_' );
data{k,2} = str2num(words{1}(2:end));
data{k,3} = str2num(words{2}(4:end));
data{k,4} = str2num(words{3}(10:end));
data{k,5} = str2num(words{4}(8:end));
end
Hi need help in using regexp for condition matching.
ex.my file has the following content
{hello.program='function'`;
bye.program='script'; }
I am trying to use regexp to match the string that has .program='function' in them:
pattern = '[.program]+\=(function)'
also tried pattern='[^\n]*(.hello=function)[^\n]*';
pattern_match = regexp(myfilename,pattern , 'match')
but this returns me pattern_match={} while i expect the result to be hello.program='function'`;
If 'function' comes with string-markers, you need to include these in the match. Also, you need to escape the dot (otherwise, it's considered "any character"). [.program]+ looks for one or several letters contained in the square brackets - but you can just look for program instead. Also, you don't need to escape the =-sign (which is probably what messed up the match).
cst = {'hello.program=''function''';'bye.program=''script'''; };
pat = 'hello\.program=''function''';
out = regexp(cst,pat,'match');
out{1}{1} %# first string from list, first match
hello.program='function'
EDIT
In response to the comment
my file contains
m2 = S.Parameter;
m2.Value = matlabstandard;
m2.Volatility = 'Tunable';
m2.Configurability = 'None';
m2.ReferenceInterfaceFile ='';
m2.DataType = 'auto';
my objective is to find all the lines that match, .DataType='auto'
Here's how you find the matching lines with regexp
%# read the file with textscan into a variable txt
fid = fopen('myFile.m');
txt = textscan(fid,'%s');
fclose(fid);
txt = txt{1};
%# find the match. Allow spaces and equal signs between DataType and 'auto'
match = regexp(txt,'\.DataType[ =]+''auto''','match')
%# match is not empty only if a match was found. Identify the non-empty match
matchedLine = find(~cellfun(#isempty,match));
Try this as it matches .program='function' exactly:
(\.)program='function'
I think this did not work:
'[.program]+\=(function)'
because of how the []'s work. Here is a link explaining why I say that: http://www.regular-expressions.info/charclass.html