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Check if a given key already exists in a dictionary and increment it
...ording to his example, it should be enough to set "defaultdict(lambda: 0)" and skip the entire "if" clause.
– Deestan
Jan 23 '09 at 14:57
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Why do x86-64 instructions on 32-bit registers zero the upper part of the full 64-bit register?
...ould almost never be used. (Making int 64-bit would waste cache footprint and memory bandwidth; x86-64 most efficiently supports 32 and 64-bit operand sizes)
The behaviour for 8 and 16-bit operand sizes is the strange one. The dependency madness is one of the reasons that 16-bit instructions are a...
How to read a file in reverse order?
... line in reversed(open("filename").readlines()):
print line.rstrip()
And in Python 3:
for line in reversed(list(open("filename"))):
print(line.rstrip())
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Several ports (8005, 8080, 8009) required by Tomcat Server at localhost are already in use
... You can confirm this by going to http://localhost:8080 in your webbrowser and check if you get the Tomcat default home page or a Tomcat-specific 404 error page. Both are equally valid evidence that Tomcat runs fine; if it didn't, then you would have gotten a browser specific HTTP connection timeout...
How do I delete an item or object from an array using ng-click?
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To remove item you need to remove it from array and can pass bday item to your remove function in markup. Then in controller look up the index of item and remove from array
<a class="btn" ng-click="remove(item)">Delete</a>
Then in controller:
$scope.remove ...
ggplot with 2 y axes on each side and different scales
I need to plot a bar chart showing counts and a line chart showing rate all in one chart, I can do both of them separately, but when I put them together, I scale of the first layer (i.e. the geom_bar ) is overlapped by the second layer (i.e. the geom_line ).
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How do I pass a variable by reference?
...n seems unclear about whether parameters are passed by reference or value, and the following code produces the unchanged value 'Original'
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Generate a random double in a range
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To generate a random value between rangeMin and rangeMax:
Random r = new Random();
double randomValue = rangeMin + (rangeMax - rangeMin) * r.nextDouble();
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Python: Continuing to next iteration in outer loop
...tinue loop i
In a general case, when you have multiple levels of looping and break does not work for you (because you want to continue one of the upper loops, not the one right above the current one), you can do one of the following
Refactor the loops you want to escape from into a function
def ...
What is a Context Free Grammar?
...to me what a context free grammar is? After looking at the Wikipedia entry and then the Wikipedia entry on formal grammar, I am left utterly and totally befuddled. Would someone be so kind as to explain what these things are?
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