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Using Regular Expressions to Extract a Value in Java
I have several strings in the rough form:
13 Answers
13
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Saving a Numpy array as an image
...Works with matplotlib 1.3.1, I don't know about lower version. From the docstring:
Arguments:
*fname*:
A string containing a path to a filename, or a Python file-like object.
If *format* is *None* and *fname* is a string, the output
format is deduced from the extension of the filename...
Best way to track onchange as-you-type in input type=“text”?
...n. If a user holds down a key, the event will only fire once for the first character. onkeypress fires whenever a char is added to the text field.
– fent
Mar 12 '12 at 17:22
62
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What is a NullPointerException, and how do I fix it?
...your code can help avoid null pointer exception. eg when checking an input string with a constant string you should start with the constant string like here: if ("SomeString".equals(inputString)) {} //even if inputString is null no exception is thrown. So there are a bunch of things that you can do ...
What are some uses of decltype(auto)?
... The example that always prompts this disgust is the one-liner file-to-string syntax (also mentioned in that link). Every part of it seems backward. You might not expect ambiguity at all, and remove redundant parentheses from a sample compulsively; you would expect ambiguity to resolve by proces...
What are the “standard unambiguous date” formats for string-to-date conversion in R?
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This is documented behavior. From ?as.Date:
format: A character string. If not specified, it will try
'"%Y-%m-%d"' then '"%Y/%m/%d"' on the first non-'NA' element,
and give an error if neither works.
as.Date("01 Jan 2000") yields an error because the format isn'...
Does C# have extension properties?
...t syntactic sugar adding a possibility to define an extended property like string Data(this MyClass instance) as an alias for extension method string GetData(this MyClass instance) as it stores data into the class.
I hope that C#7 will provide a full featured extension everything (properties and fi...
SQLAlchemy: Creating vs. Reusing a Session
... of expire_on_commit pretty much optional, as this flag can incur a lot of extra SQL for an operation that calls commit() in the middle of a series of operations. Not sure if this answers your question.
The next round is what you mention about threading. If your app is multithreaded, we recomme...
SQL Server equivalent to MySQL enum data type?
... then you'll end-up adding lots of tables to your database. Not to mention extra IO reads due to FK constraint-checking when inserting/deleting data, whereas a CHECK CONSTRAINT is much faster and doesn't cause database object spam.
– Dai
Sep 18 at 7:23
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Specify format for input arguments argparse python
...rsions to be performed ... type= can take any callable that takes a single string argument and returns the converted value
You could do something like:
def valid_date(s):
try:
return datetime.strptime(s, "%Y-%m-%d")
except ValueError:
msg = "Not a valid date: '{0}'.".forma...