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How to list variables declared in script in bash?
In my script in bash, there are lot of variables, and I have to make something to save them to file.
My question is how to list all variables declared in my script and get list like this:
...
Send string to stdin
...
This is coming from the stdin
EOF
or you can redirect output from a command, like
diff <(ls /bin) <(ls /usr/bin)
or you can read as
while read line
do
echo =$line=
done < some_file
or simply
echo something | read param
...
How to convert comma-delimited string to list in Python?
...igit() else e for e in mStr.split(',')]
It is called list comprehension, and it is based on set builder notation.
ex:
>>> mStr = "1,A,B,3,4"
>>> mList = [int(e) if e.isdigit() else e for e in mStr.split(',')]
>>> mList
>>> [1,'A','B',3,4]
...
Understanding the map function
Apply function to every item of iterable and return a list of the results. If additional iterable arguments are passed, function must take that many arguments and is applied to the items from all iterables in parallel.
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Behaviour of increment and decrement operators in Python
...erator is the identity operator, which does nothing. (Clarification: the + and - unary operators only work on numbers, but I presume that you wouldn't expect a hypothetical ++ operator to work on strings.)
++count
Parses as
+(+count)
Which translates to
count
You have to use the slightly lo...
Scala: What is the difference between Traversable and Iterable traits in Scala collections?
I have looked at this question but still don't understand the difference between Iterable and Traversable traits. Can someone explain ?
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CSS “and” and “or”
... Ok, thanks for light. I hate styling forms, but it's my task, and site isn't mine. I'll apply classes to inputs.
– Misiur
May 9 '10 at 9:02
5
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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
How can I achieve the equivalents of SQL's IN and NOT IN ?
9 Answers
9
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AJAX POST and Plus Sign ( + ) — How to Encode?
I'm POSTing the contents of a form field via AJAX to a PHP script and using JavaScript to escape(field_contents) . The problem is that any plus signs are being stripped out and replaced by spaces. How can I safely 'encode' the plus sign and then appropriately 'decode' it on the PHP side?
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Why are quaternions used for rotations?
I'm a physicist, and have been learning some programming, and have come across a lot of people using quaternions for rotations instead of writing things in matrix/vector form.
...