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Convert a number range to another range, maintaining ratio
...es oldMax have to be 16000 or can it be the highest value in the old point set (say, 15034.00, for example) is the distinction important?
– SpliFF
May 30 '09 at 6:30
5
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PHP: exceptions vs errors?
...
I usually set_error_handler to a function that takes the error and throws an exception so that whatever happens i'll just have exceptions to deal with. No more @file_get_contents just nice and neat try/catch.
In debug situations i als...
Does the ternary operator exist in R?
...t even better because it is also vectorized. An example using the cars dataset:
> cars$speed > 20
[1] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
[13] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
[25] FALSE FALSE FALSE FALSE FALSE FALSE ...
Can you have multiline HTML5 placeholder text in a ?
I have ghost text in textfields that disappear when you focus on them using HTML5's placeholder attribute:
15 Answers
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MySQL: #126 - Incorrect key file for table
...filesystem and mysql ran out of space writing a temp table there. I had to set the tmpdir config variable as mentioned on mysql.com
– jcbwlkr
Nov 5 '13 at 18:26
1
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.NET data structures: ArrayList, List, HashTable, Dictionary, SortedList, SortedDictionary — Speed,
...SortedDictionary
Another collection that was added in .NET 3.5 is the Hashset. It is a collection that supports set operations.
Also, the LinkedList is a standard linked-list implementation (the List is an array-list for faster retrieval).
...
Visual Studio: Multiple post-build commands?
...ve different post-build steps on different machines. VS 2008 doesn't allow setting PostBuildStep in property sheets directly, but you can add a user macro with your command and call it from the main project settings. A macro is single line, so you can use && to have multiple commands there.
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How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...objects (like lists, for example). Even if your values are hashable, since sets are semantically unordered, the behavior is undefined in regards to precedence. So don't do this:
>>> c = dict(a.items() | b.items())
This example demonstrates what happens when values are unhashable:
>>&...
What are the differences between numpy arrays and matrices? Which one should I use?
What are the advantages and disadvantages of each?
5 Answers
5
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Queue.Queue vs. collections.deque
...append methods have a
DECREF at the end (for cases where maxlen has been set), but this
happens after all of the structure updates have been made and the
invariants have been restored, so it is okay to treat these operations
as atomic.
Anyway, if you are not 100% sure and you prefer reliab...