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Swap key with value JSON
...nfirm, is it? Performance good? Semantic is perfect: we can see that is really a simple "map and swap" solution.
– Peter Krauss
Jan 3 '19 at 17:41
1
...
How can I initialize base class member variables in derived class constructor?
...ince it would destroy encapsulation. Instead, create a constructor in A to allow B (or any subclass of A) to initialize them:
class A
{
protected:
A(int a, int b) : a(a), b(b) {} // Accessible to derived classes
// Change "protected" to "public" to allow others to instantiate A.
private:
...
How to select rows from a DataFrame based on column values?
...have multiple values you want to include, put them in a
list (or more generally, any iterable) and use isin:
print(df.loc[df['B'].isin(['one','three'])])
yields
A B C D
0 foo one 0 0
1 bar one 1 2
3 bar three 3 6
6 foo one 6 12
7 foo three 7 14
Note,...
How to use SSH to run a local shell script on a remote machine?
...ssh user@host2 <<'END2'
# Another bunch of commands on another host
wall <<'ENDWALL'
Error: Out of cheese
ENDWALL
ftp ftp.secureftp-test.com <<'ENDFTP'
test
test
ls
ENDFTP
END2
ENDSSH
You can actually have a conversation with some services like telnet, ftp, etc. But remember that...
Installing R with Homebrew
I'm trying to install R using Homebrew. I ran these commands which are recommended elsewhere on SO:
12 Answers
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What is the Swift equivalent to Objective-C's “@synchronized”?
...ty that you have with @synchronized.
– Michael Waterfall
Oct 23 '14 at 16:46
9
With this approach...
How can I check if an ip is in a network in Python?
...
Additionally, struct.unpack('L',socket.inet_aton(ip))[0] will fail on architectures where 'L' unpacks to something different than 4 bytes, regardless of endianness.
– Rafał Dowgird
May 4 '09 at...
“PKIX path building failed” and “unable to find valid certification path to requested target”
...
Note that instructions should be repeated for all certificates in the chain. Also certificate's alias name in command line should be unique.
– Lu55
Sep 12 '17 at 18:50
...
Undefined symbols for architecture armv7
... header and do not link against the correct library. This is common, especially for headers for libraries like QuartzCore since it is not included in projects by default. To resolve:
Add the correct libraries in the Link Binary With Libraries section of the Build Phases.
If you want to add a libra...
Getting realtime output using subprocess
...pe, no communicate() method on the returned CompletedProcess. Also, capture_output is mutually exclusive with stdout and stderr.
– Aidan Feldman
Apr 19 '19 at 3:03
add a comme...