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How to import multiple .csv files at once?
...t;-
list.files(pattern = "*.csv") %>%
map_df(~fread(.))
The stringsAsFactors = FALSE argument keeps the dataframe factor free, (and as marbel points out, is the default setting for fread)
If the typecasting is being cheeky, you can force all the columns to be as characters with the c...
How to convert List to List?
... @markthewizard1234 That will happen if your listofIDs is an IQueryable<string> that has not been executed. Execute it first with ToList() before you do the conversion: listofIDs.ToList().Select(int.Parse).ToList()
– Michael Hornfeck
Jun 13 '16 at 19:59
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How do I filter query objects by date range in Django?
...n think of is as suggested in my original response, which is to supply the extra 'padding' for comparison against a datetime model field when you're filtering against a date instance. This can be done via the datetime.combine method as above, but I've found that it can be a bit simpler to merely ac...
Convert data.frame column format from character to factor
... the format (class) of some columns of my data.frame object ( mydf ) from charactor to factor .
6 Answers
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How to check whether a file is empty or not?
...irst_char:
... print "file is empty" #first character is the empty string..
... else:
... my_file.seek(0) #first character wasn't empty, return to start of file.
... #use file now
...
file is empty
...
What datatype to use when storing latitude and longitude data in SQL databases? [duplicate]
...,6)
If you're not used to precision and scale parameters, here's a format string visual:
###.###### and ##.######
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How to count certain elements in array?
...gt; 1}
> counts.remove('a')
Uncaught tried to remove element a of type string from Multiset, but does not exist in Multiset (count is 0 and cannot go negative)
sidenote: Though, if you still wanted the functional-programming way (or a throwaway one-liner without overriding Array.prototype), yo...
Email validation using jQuery
...l could be written in better way. None part of domain can start with other char than [a-z0-9] (case insensitive). Also, valid e-mail (and domain) has some len limit, which is also not tested.
– tomis
Jul 5 '13 at 8:42
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Dump a NumPy array into a csv file
...d works well for numerical data, but it throws an error for numpy.array of strings. Could you prescribe a method to save as csv for an numpy.array object containing strings?
– Ébe Isaac
Mar 25 '16 at 14:31
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How to avoid installing “Unlimited Strength” JCE policy files when deploying an application?
... // This matches Oracle Java 7 and 8, but not Java 9 or OpenJDK.
final String name = System.getProperty("java.runtime.name");
final String ver = System.getProperty("java.version");
return name != null && name.equals("Java(TM) SE Runtime Environment")
&& ver !=...