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What does “Object reference not set to an instance of an object” mean? [duplicate]
... AND for myPet.PetType == null
if ( myPet.PetType == "cat" ) <--- fall down go boom!
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A clean, lightweight alternative to Python's twisted? [closed]
...asynchronous server.
I suppose it's similar to Eventlet in this way.
The downside is that its API is quite different from Python's sockets/threading modules; you need to rewrite a fair bit of your application (or write a compatibility shim layer)
Edit: It seems that there's also cogen, which is s...
Reduce left and right margins in matplotlib plot
... need is
plt.tight_layout()
before your output.
In addition to cutting down the margins, this also tightly groups the space between any subplots:
x = [1,2,3]
y = [1,4,9]
import matplotlib.pyplot as plt
fig = plt.figure()
subplot1 = fig.add_subplot(121)
subplot1.plot(x,y)
subplot2 = fig.add_subp...
Why should I use Deque over Stack?
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Performance might be a reason. An algorithm I used went down from 7.6 minutes to 1.5 minutes by just replacing Stack with Deque.
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How to recursively delete an entire directory with PowerShell 2.0?
...n my box, and had tried rm -rf folder and of course it failed. I initially down voted the answer (because it said Ubuntu). Thanks to the comment by @chwarr, I tried it without the f and it picked up the alias rather than rm binary. I wish Tuan would update his source (not sure if Tuan knew it was an...
AWK: Access captured group from line pattern
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That was a stroll down memory lane...
I replaced awk by perl a long time ago.
Apparently the AWK regular expression engine does not capture its groups.
you might consider using something like :
perl -n -e'/test(\d+)/ && print $1'
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Git alias with positional parameters
...nch -u $2 #". This works great without the first two statements, but falls down if you use them. (I have headBranch = symbolic-ref --short HEAD as well).
– gib
Aug 12 '17 at 19:17
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JSF backing bean structure (best practices)
...The typical use case is supplying an ArrayList to JSF h:selectOneMenu drop-down lists that appear in more than one JSF view. If the data in the dropdown lists is particular to the user, then the bean would be kept in session scope. However, if the data applies to all users (such as a dropdown lists ...
How can a time function exist in functional programming?
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RealWorld -> (a, RealWorld) does not break down as metaphor even under concurrency, as long as you keep in mind that the real world might be changed by other parts of the universe outside of your function (or your current process) at all times. So (a) the methaphor do...
Formatting Decimal places in R
...ies, I've just tried it with 5.565 which does round up, while 5.545 rounds down. I guess it is the way they are handling floating point inprecision. I don't think I've seen this behaviour in other languages which I guess means they have a built-in workaround
– Mark Adamson
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