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Applying a function to every row of a table using dplyr?
... the intersection of purrr and dplyr. They have been removed from purrr in order to make the package lighter and because they have been replaced by other solutions in the tidyverse.
So, you will need to install + load that package to make the code below work.
Original post
Hadley frequently chan...
Using try vs if in python
...xpected never to be empty (but might be, if, for instance, a disk crashed, etc), the second approach makes sense. If, on the other hand, an empty result is perfectly reasonable under normal conditions, testing for it with an if statement makes more sense.
I had in mind the (more common) scenario:
...
Add only non-whitespace changes
... someone else might also contribute a solution for people using Sublesion, etc.
– Steve Pitchers
Jul 24 '15 at 10:30
1
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How to disable the application pool idle time-out in IIS7?
...any setting on a high traffic site you should always test for side effects etc on your staging/QA environment. Also during the time you're applying the change to your production environment then you really ought to throw up a maintenance page for public facing users until such time the change has ta...
How to open every file in a folder?
...rent directory using os.listdir:
import os
for filename in os.listdir(os.getcwd()):
with open(os.path.join(os.cwd(), filename), 'r') as f: # open in readonly mode
# do your stuff
Glob
Or you can list only some files, depending on the file pattern using the glob module:
import glob
for ...
How to make a class property? [duplicate]
... base classes of type(a) excluding metaclasses.
So the method resolution order doesn't include our class properties (or anything else defined in the metaclass). It is possible to make a subclass of the built-in property decorator that behaves differently, but (citation needed) I've gotten the impr...
Replace transparency in PNG images with white background
...and applying background image is straight forward in ImageMagick
However, order of the commands is very important
To apply any background on a transparent image and flatten it, first apply the background than flatten it. The reverse doesn't work.
$ convert sourceimage.png -background BackgroundC...
How can I enable zoom in on UIWebView which inside the UIScrollView?
...
Hi, It all working fine Paging, ZoomIn/Out, etc... But I have one issue in that. My app working in both orientation (Portrait & Landscape). Now, in portrait, I have to swipe the page 2-3 times then I am able to go next page. But in landscape, it's working fine. I h...
Python requests - print entire http request (raw)?
...the simple response = requests.post(...) (or requests.get or requests.put, etc) methods, you can actually get the PreparedResponse through response.request. It can save the work of manually manipulating requests.Request and requests.Session, if you don't need to access the raw http data before you r...
How to get the caller's method name in the called method?
...ler
name. skip=1 means "who calls me", skip=2 "who calls my caller" etc.
An empty string is returned if skipped levels exceed stack height
"""
stack = inspect.stack()
start = 0 + skip
if len(stack) < start + 1:
return ''
parentframe = stack[start][0]
...