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Argparse: Required arguments listed under “optional arguments”?
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Parameters starting with - or -- are usually considered optional. All other parameters are positional parameters and as such required by design (like positional function arguments). It is possible to require optional arguments, but this is a bit against their desig...
Select by partial string from a pandas DataFrame
...egex search is not required, so specify regex=False to disable it.
#select all rows containing "foo"
df1[df1['col'].str.contains('foo', regex=False)]
# same as df1[df1['col'].str.contains('foo')] but faster.
col
0 foo
1 foobar
Performance wise, regex search is slower than substring s...
querySelector, wildcard element match?
...to do a wildcard element name match using querySelector or querySelectorAll ? I see support for wildcards in attribute queries but not for the elements themselves.
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How do you pass arguments to define_method?
... your defined method accepts arguments. When you define a method you're really just nicknaming the block and keeping a reference to it in the class. The parameters come with the block. So:
define_method(:say_hi) { |other| puts "Hi, " + other }
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How to delete duplicates on a MySQL table?
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The above query deleted all of my records except one :(
– Zolbayar
Aug 10 at 3:21
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Overriding a Rails default_scope
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Short answer: Do not use default_scope unless you really have to. You'll probably be better off with named scopes. With that said, you can use with_exclusive_scope to override the default scope if you need to.
Have a look at this question for more details.
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Setting an environment variable before a command in Bash is not working for the second command in a
In a given shell, normally I'd set a variable or variables and then run a command. Recently I learned about the concept of prepending a variable definition to a command:
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Is it possible to make the -init method private in Objective-C?
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Objective-C, like Smalltalk, has no concept of "private" versus "public" methods. Any message can be sent to any object at any time.
What you can do is throw an NSInternalInconsistencyException if your -init method is invoked:
- (id)init {
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How can I recursively find all files in current and subfolders based on wildcard matching?
How can I recursively find all files in current and subfolders based on wildcard matching?
16 Answers
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Creating functions in a loop
...have a function that accesses a global variable, like this:
global_var = 'foo'
def my_function():
print(global_var)
global_var = 'bar'
my_function()
When you read this code, you would - of course - expect it to print "bar", not "foo", because the value of global_var has changed after the fu...