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Drop data frame columns by name
...d like to remove from a data frame. I know that we can delete them individually using something like:
20 Answers
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Can I use the range operator with if statement in Swift?
...nt with an expression pattern (which uses the pattern-match
operator internally):
switch statusCode {
case 200 ... 299:
print("success")
default:
print("failure")
}
Note that ..< denotes a range that omits the upper value, so you probably want
200 ... 299 or 200 ..< 300.
Additional...
InputStream from a URL
...
Calling this method in UI thread in Android will raise an exception. Do it in a background thread. Use Bolts-Android
– Behrouz.M
Mar 6 '19 at 10:16
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How to get an enum value from a string value in Java?
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@treesAreEverywhere More specifically, those methods are generated (or synthesized) by the compiler. The actual enum Blah {...} definition shouldn't try to declare its own values nor valuesOf. It's like how you can write "AnyTypeName.class" even though you...
Sort hash by key, return hash in Ruby
...
In Ruby 2.1 it is simple:
h.sort.to_h
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How do I get both STDOUT and STDERR to go to the terminal and a log file?
...ut
or
./a.out |& tee output
In csh, there is a built-in command called "script" that will capture everything that goes to the screen to a file. You start it by typing "script", then doing whatever it is you want to capture, then hit control-D to close the script file. I don't know of an ...
Python Create unix timestamp five minutes in the future
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Now in Python >= 3.3 you can just call the timestamp() method to get the timestamp as a float.
import datetime
current_time = datetime.datetime.now(datetime.timezone.utc)
unix_timestamp = current_time.timestamp() # works if Python >= 3.3
unix_timestamp_pl...
No Multiline Lambda in Python: Why not?
...ltiline lambdas can't be added in Python because they would clash syntactically with the other syntax constructs in Python. I was thinking about this on the bus today and realized I couldn't think of a single Python construct that multiline lambdas clash with. Given that I know the language pretty...
warning this call is not awaited, execution of the current method continues
...
If you really don't need the result, you can simply change the GetNameAsync's signature to return void:
public static async void GetNameAsync()
{
...
}
Consider to see answer to a related question:
What's the difference between...
How to write a:hover in inline CSS?
...defining the selection criteria).
Response to the OP's comments:
See Totally Pwn CSS with Javascript for a good script on adding CSS rules dynamically. Also see Change style sheet for some of the theory on the subject.
Also, don't forget, you can add links to external stylesheets if that's an op...