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Python: Get the first character of the first string in a list?
...ist char for the first one string(item):
myList[0][0]
>>> b
If all first chars:
[x[0] for x in myList]
>>> ['b', 's', 't']
If you have a text:
text = 'base sample test'
text.split()[0][0]
>>> b
...
How to set IntelliJ IDEA Project SDK
I just installed IntelliJ IDEA and when I try to create my first Project it asks for me to set up the Project SDK. When I click on "JDK" it asks for me to select the home directory of the JDK as shown in this image.
...
Deep null checking, is there a better way?
...'d say
cake?.frosting?.berries?.loader
and the compiler would generate all the short-circuiting checks for you.
It didn't make the bar for C# 4. Perhaps for a hypothetical future version of the language.
Update (2014):
The ?. operator is now planned for the next Roslyn compiler release. Note ...
How to Load an Assembly to AppDomain with all references recursively?
...e I wrote to solve this problem: github.com/jduv/AppDomainToolkit. Specifically, look at the LoadAssemblyWithReferences method in this class: github.com/jduv/AppDomainToolkit/blob/master/AppDomainToolkit/…
– Jduv
Mar 14 '13 at 14:44
...
TypeScript function overloading
...use, when both functions are compiled to JavaScript, their signature is totally identical. As JavaScript doesn't have types, we end up creating two functions taking same number of arguments. So, TypeScript restricts us from creating such functions.
TypeScript supports overloading based on number of...
If table exists drop table then create it, if it does not exist just create it
...s case than not to cover, see locking note below).
Second RENAME ... atomically replaces table definition, refer to
MySQL manual
for details.
At last, DROP ... just cleans up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK...
Please explain the exec() function and its family
...
Simplistically, in UNIX, you have the concept of processes and programs. A process is an environment in which a program executes.
The simple idea behind the UNIX "execution model" is that there are two operations you can do.
The first ...
Is there a way to detach matplotlib plots so that the computation can continue?
...
Use matplotlib's calls that won't block:
Using draw():
from matplotlib.pyplot import plot, draw, show
plot([1,2,3])
draw()
print('continue computation')
# at the end call show to ensure window won't close.
show()
Using interactive mode:
from...
How do you rename a Git tag?
...'t do this, Git will create the old tag on your machine when you pull.
Finally, make sure that the other users remove the deleted tag. Please tell them (co-workers) to run the following command:
git pull --prune --tags
Note that if you are changing an annotated tag, you need ensure that the ne...
What's the best way to add a drop shadow to my UIView
...shadow to views that are layered on top of one another, the views collapse allowing content in other views to be seen, in this vein i want to keep view.clipsToBounds ON so that when the views collapse their content is clipped.
...