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Append column to pandas dataframe
...efore you join() or concat() if you trying to deal with some data frame by selecting some rows from another DataFrame.
One example below shows some interesting behavior of join and concat:
dat1 = pd.DataFrame({'dat1': range(4)})
dat2 = pd.DataFrame({'dat2': range(4,8)})
dat1.index = [1,3,5,7]
dat...
How many socket connections can a web server handle?
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The clients would randomly select a server. The chances of all randomly connecting to one is practically impossible. Although one could follow up with client count and the server could ask a client to move to another server if too overcrowded.
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How to encrypt/decrypt data in php?
...se of mcrypt can be found in this manual. A list of cipher definitions to select the cipher mcrypt uses also exists. A wiki on Blowfish can be found at Wikipedia. A block cipher encrypts the input in blocks of known size and position with a known key, so that the data can later be decrypted using...
Software Design vs. Software Architecture [closed]
..., some component’s internal design decisions, like- choice of algorithm, selection of data structure etc.
Any design decision, which isn’t visible outside of its component boundary is a component’s internal design and is non-architectural. These are the design decisions a system architect woul...
How to add an Access-Control-Allow-Origin header
...for the file
scroll down to the file
click the cog icon
click Edit Headers
select Access-Control-Allow-Origin
add the single character '*' (without the quotes)
hit enter
repeat for the other files
If you need to continue and do #2, then you'll need a command line with CURL
curl -D - --header "X-A...
When applying a patch is there any way to resolve conflicts?
... You can also right drag patches on a working tree folder and select "Apply patch serial" (for patches like 0001-xxx.patch, ... 0002-xxy.patch) or "Apply single patch file".
– MrTux
Sep 6 '15 at 19:24
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What is the performance cost of having a virtual method in a C++ class?
..."type(-identifying) number" in the objects and using a switch statement to select the type-specific code. This avoids function call overhead completely - just doing a local jump. There is a potential cost to maintainability, recompilation dependencies etc through the forced localisation (in the sw...
Forcing a WPF tooltip to stay on the screen
...to persist longer without further fanfare. Doing this still allows you to selectively apply a smaller value in context-specific places, as well, exactly as in the other answer. (But as always, this is only valid if you are the application -- if you're writing a control library or something else th...
Why is “except: pass” a bad programming practice?
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Try to avoid passing in except blocks
When explicitly catching a small selection of specific exceptions, there are many situations in which we will be fine by simply doing nothing. In such cases, just having except SomeSpecificException: pass is just fine. Most of the time though, this is not th...
How to attach debugger to iOS app after launch?
... the name in the Debug navigator
Plug in your device and don't forget to select your device as the target
Debug > Attach to Process > By Process Identifier (PID) or Name
Enter the name from step 1 and attach. That should be all you have to do.
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