I have a bunch of CSV files that have the data in a format of YYYY-MM-DD HH,value
I can split the hours off by running
with open(out_path+filename,'r+') as data_r:
comreader = csv.reader(data_r, delimiter=' ', quotechar='"')
for row in comreader:
print ','.join(row)
from this I get
'YYYY-MM-DD,HH',value
What I need to do is remove the (') from in front of YYYY and then after HH
You're using the quotechar parameter, but wrongly:
it should read "'" if you want to interpret ' as the character surrounding strings.
Other than that, you can get parts of strings easily with python's slicing abilities:
outstring = instring[1:-1]
will give you everything from the 1. (dropping the 0.) to (excluding it) the last character.
Related
Context
I am designing a code that runs a bunch of calculations, and outputs figures. At the end of the code, I want to save everything in a nice way, so my take on this is to go to a user specified Output directory, create a new folder and then run the save process.
Question(s)
My question is twofold:
I want my folder name to be unique. I was thinking about getting the current date and time and creating a unique name from this and the input filename. This works but it generates folder names that are a bit cryptic. Is there some good practice / convention I have not heard of to do that?
When I get the datetime string (tn = datestr(now);), it looks like that:
tn =
'07-Jul-2022 09:28:54'
To convert it to a nice filename, i replace the '-',' ' and ':' characters by underscores and append it to a shorter version of the input filename chosen by the user. I do that using strrep:
tn = strrep(tn,'-','_');
tn = strrep(tn,' ','_');
tn = strrep(tn,':','_');
This is fine but it bugs me to have to use 3 lines of code to do so. Is there a nice one liner to do that? More generally, is there a way to look for every non letter or number character in a string and replace it with a given character? I bet that's what regexp is there for but frankly I can't quite get a hold on how regexps work.
Your point (1) is opinion based so you might get a variety of answers, but I think a common convention is to at least start the name with a reverse-order date string so that sorting alphabetically is the same as sorting chronologically (i.e. yymmddHHMMSS).
To answer your main question directly, you can use the built-in makeValidName utility which is designed for making valid variable names, but works for making similarly "plain" file names.
str = '07-Jul-2022 09:28:54';
str = matlab.lang.makeValidName(str)
% str = 'x07_Jul_202209_28_54'
Because a valid variable can't start with a number, it prefixes an x - you could avoid this by manually prefixing something more descriptive first.
This option is a bit more simple than working out the regex, although that would be another option which isn't too nasty here using regexprep and replacing non-alphanumeric chars with an underscore:
str = regexprep( str, '\W', '_' ); % \W (capital W) matches all non-alphanumeric chars
% str = '07_Jul_2022_09_28_54'
To answer indirectly with a different approach, a nice trick with datestr which gets around this issue and addresses point (1) in one hit is to use the following syntax:
str = datestr( now(), 30 );
% str = '20220707T094214'
The 30 input (from the docs) gives you an ISO standardised string to the nearest second in reverse-order:
'yyyymmddTHHMMSS' (ISO 8601)
(note the T in the middle isn't a placeholder for some time measurement, it remains a literal letter T to split the date and time parts).
I normally use your folder naming approach with a meaningful prefix, replacing ':' by something else:
folder_name = ['results_' strrep(datestr(now), ':', '.')];
As for your second question, you can use isstrprop:
folder_name(~isstrprop(folder_name, 'alphanum')) = '_';
Or if you want more control on the allowed characters you can use good old ismember:
folder_name(~ismember(folder_name, ['0':'9' 'a':'z' 'A':'Z'])) = '_';
I wrote a code that automatically pulls time-related information from the system. As indicated in the table is fixed t247 Month names to 10 characters in length. But it is a bad image when showing on the report screen.
I print this way:
WRITE : 'Bugün', t_month_names-ltx, ' ayının'.
CONCATENATE gv_words-word '''nci günü' INTO date.
CONCATENATE date ',' INTO date.
CONCATENATE date gv_year INTO date SEPARATED BY space.
TRANSLATE date TO LOWER CASE.
I tried the CONDENSE t_month_names-ltx NO-GAPS. method to delete the spaces, but it was not enough.
After WRITE, I was able to write statically by setting the blank value:
WRITE : 'Bugün', t_month_names-ltx.
WRITE : 14 'ayının'.
CONCATENATE gv_words-word '''nci günü' INTO date.
CONCATENATE date ',' INTO date.
CONCATENATE date gv_year INTO date SEPARATED BY space.
TRANSLATE date TO LOWER CASE.
But this is not a correct use. How do I achieve this dynamically?
You could use a temporary field of type STRING:
DATA l_month TYPE STRING.
l_month = t_month_names-ltx.
WRITE : 'Bugün', l_month.
WRITE : 14 'ayının'.
CONCATENATE gv_words-word '''nci günü' INTO date.
CONCATENATE date ',' INTO date.
CONCATENATE date gv_year INTO date SEPARATED BY space.
TRANSLATE date TO LOWER CASE.
You can not delete trailing spaces from a TYPE C field, because it's of constant length. The unused length is always filled with spaces.
But after you assembled you string, you can use CONDENSE without NO-GAPS to remove any chains of more than one space within the string.
Add CONDENSE date. below the code you wrote and you should get the results you want.
Another option is to abandon CONCATENATE and use string templates (string literals within | symbols) for string assembly instead, which do not have the annoying habit of including trailing spaces of TYPE C fields:
DATA long_char TYPE C LENGTH 128.
long_char = 'long character field'.
WRITE |this is a { long_char } inserted without spaces|.
Output:
this is a long character field inserted without spaces
I am trying to write a Powershell code to identify a string with a specific character from a filename from multiple files.
An example of a filename
20190902091031_202401192_50760_54206_6401.pdf
$Variable = $Filename.Substring(15,9)
Results:
202401192 (this is what I am after)
However in some instances the filename will be like below
20190902091031_20240119_50760_54206_6401.pdf
$Variable = $Filename.Substring(15,9)
Results:
20240119_ (this is NOT what I am after)
I am trying to find a code to identify the 9th character,
IF the 9th character = "_"
THEN Set
$Variable = $Filename.Substring(15,8)
Results:
20240119
All credit to TheMadTechnician who beat me to the punch with this answer.
To expand on the technique a bit, use the split method or operator to split a string every time a certain character shows up. Your data is separated by the underscore character, so is a perfect example of using this technique. By using either of the following:
$FileName.Split('_')
$FileName -split '_'
You can turn your long string into an array of shorter strings, each containing one of the parts of your original string. Since you want the 2nd one, you use the array descriptor [1] (0 is 1st) and you're done.
Good luck
So I'm reading multiple text files in Matlab that have, in their first columns, a column of "times". These times are either in the format 'MM:SS.milliseconds' (sorry if that's not the proper way to express it) where for example the string '29:59.9' would be (29*60)+(59)+(.9) = 1799.9 seconds, or in the format of straight seconds.milliseconds, where '29.9' would mean 29.9 seconds. The format is the same for a single file, but varies across different files. Since I would like the times to be in the second format, I would like to check if the format of the strings match the first format. If it doesn't match, then convert it, otherwise, continue. The code below is my code to convert, so my question is how do I approach checking the format of the string? In otherwords, I need some condition for an if statement to check if the format is wrong.
%% Modify the textdata to convert time to seconds
timearray = textdata(2:end, 1);
if (timearray(1, 1) %{has format 'MM.SS.millisecond}%)
datev = datevec(timearray);
newtime = (datev(:, 5)*60) + (datev(:, 6));
elseif(timearray(1, 1) %{has format 'SS.millisecond}%)
newtime = timearray;
You can use regular expressions to help you out. Regular expressions are methods of specifying how to search for particular patterns in strings. As such, you want to find if a string follows the formats of either:
xx:xx.x
or:
xx.x
The regular expression syntax for each of these is defined as the following:
^[0-9]+:[0-9]+\.[0-9]+
^[0-9]+\.[0-9]+
Let's step through how each of these work.
For the first one, the ^[0-9]+ means that the string should start with any number (^[0-9]) and the + means that there should be at least one number. As such, 1, 2, ... 10, ... 20, ... etc. is valid syntax for this beginning. After the number should be separated by a :, followed by another sequence of numbers of at least one or more. After, there is a . that separates them, then this is followed by another sequence of numbers. Notice how I used \. to specify the . character. Using . by itself means that the character is a wildcard. This is obviously not what you want, so if you want to specify the actual . character, you need to prepend a \ to the ..
For the second one, it's almost the same as the first one. However, there is no : delimiter, and we only have the . to work with.
To invoke regular expressions, use the regexp command in MATLAB. It is done using:
ind = regexp(str, expression);
str represents the string you want to check, and expression is a regular expression that we talked about above. You need to make sure you encapsulate your expression using single quotes. The regular expression is taken in as a string. ind would this return the starting index of your string of where the match was found. As such, when we search for a particular format, ind should either be 1 indicating that we found this search at the beginning of the string, or it returns empty ([]) if it didn't find a match. Here's a reproducible example for you:
B = {'29:59.9', '29.9', '45:56.8', '24.5'};
for k = 1 : numel(B)
if (regexp(B{k}, '^[0-9]+:[0-9]+\.[0-9]+') == 1)
disp('I''m the first case!');
elseif (regexp(B{k}, '^[0-9]+\.[0-9]+') == 1)
disp('I''m the second case!');
end
end
As such, the code should print out I'm the first case! if it follows the format of the first case, and it should print I'm the second case! if it follows the format of the second case. As such, by running this code, we get:
I'm the first case!
I'm the second case!
I'm the first case!
I'm the second case!
Without knowing how your strings are formatted, I can't do the rest of it for you, but this should be a good start for you.
I have a bit of Matlab code and I am trying to export some string and create a tab-delimitted text file from it. I think fprintf performs similarly in C (if not please edit my tag). I believe my issue is with my format string. Basically I have 7 strings that I want separated by tabs and then a newline character. please note that "fid" is a full path. I am looping this in a for loop so lines are being appended each pass and the file is built.
ImgData = strcat(ImgData, fid, '\t', imgNumber, '\t', N_std,'\t',S,'\t',N,'\t',SNR,'\t',SNR_dB,'\n');
DataOut = fopen(strcat('Image_F', folderNumber, '_Data.txt'), 'w');
fprintf(DataOut,'%s\t %s\t %s\t %s\t %s\t %s\t %s\n',ImgData);
You may be curious on how this exports. This formats like
fid\tI#\tN_std\tS\tN\tSNR\tSNR_dB\n
in the txt file. As you can tell this isn't tab-delimitted which my major issue. I am having some trouble with the format string. Does anyone know how to reformat it so it prints the tabs and newline?
You're creating a string in ImgData that you then pass as input to fprintf. This reads ImgData into the first %s of the format string, and then adds at least one tab at the end.
What you should do instead is write something like:
`fprintf(DataOut,'%s\t%i\n',imgName,imgNumber)`
which assumes that imgName is a string and imgNumber an integer number. Note that I pass two placeholders (with the %-sign) and two input variables to fprintf.
Use %6.2f print floating point numbers with a total of 6 characters, including 2 after the comma, for SNR, for example.
For easier development, you can drop the first input argument to fprintf, in which case it will print to command line.