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How do I delete rows in a data frame?
... :
mydata[-seq(2, nrow(mydata), by = 2) , ]
Or if you want to subset by selecting odd numbers:
mydata[which(1:nrow(mydata) %% 2 == 1) , ]
Or if you want to subset by selecting odd numbers, version 2:
mydata[which(1:nrow(mydata) %% 2 != 0) , ]
Or if you want to subset by filtering even numbe...
Will using 'var' affect performance?
... that were expecting a variable of type int because it can't automatically convert the float, but that's exactly the same thing that would happen if you explicitly used int and then changed to float. In any case, your answer still does not answer the question of "does using var affect performance?" ...
Send a file via HTTP POST with C#
....ASCIIEncoding.ASCII.GetBytes(sAuthorization);
string returnValue = System.Convert.ToBase64String(toEncodeAsBytes);
wr.Headers.Add("Authorization: Basic " + returnValue); //AUTHENTIFICATION END
Stream rs = wr.GetRequestStream();
string formdataTemplate = "Content-Disposition: form-data; name=\"{0}...
Error message 'Unable to load one or more of the requested types. Retrieve the LoaderExceptions prop
...an also happen if your referenced DLL is "blocked". Right click on it, and select "unblock"
– Ben
Jun 10 '10 at 10:05
4
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Python Progress Bar
...a console progress bar
## Accepts a float between 0 and 1. Any int will be converted to a float.
## A value under 0 represents a 'halt'.
## A value at 1 or bigger represents 100%
def update_progress(progress):
barLength = 10 # Modify this to change the length of the progress bar
status = ""
...
Getting binary content in Node.js using request
...s incoming data in the content of the response as UTF-8, and automatically converts any non-UTF-8 byte sequences to junk (but valid UTF-8) characters. No amount of setting 'mimetype", etc. works (not that it's supposed to for response data). The encoding: null is the only option that works. And -...
How do I break out of nested loops in Java?
...ng? Labels support either equally well (or badly!) but I'm not sure how to convert this logic for a continue.
– Rob Grant
Oct 25 '13 at 10:01
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How to fix: android.app.RemoteServiceException: Bad notification posted from package *: Couldn't cre
...save it to bundle as a string( bundle.putString("img", "my_image")and then convert when needed to actual @DrawableRes integer as follows: ctx.resources.getIdentifier(bundle.getString("img"), "drawable", ctx.packageName)
– vanomart
Jan 11 '17 at 13:04
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Refresh image with a new one at the same url
...had other arguments for the controller action so I added it as "......&convert=true&t=" + new Date().getTime(); and "......&convert=true#" + new Date().getTime();. Is there anything I am doing wrong?
– shaffooo
May 6 '16 at 16:31
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IIS does not list a website that matches the launch url
..., but only when clicking on the icon directly. Right-clicking the icon and selecting a solution to open did not open visual studio in Administrator mode though sadly. I had to use QMaster's answer to get that to work.
– user1568891
Jul 27 '16 at 16:26
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