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Equation (expression) parser with precedence?
...'ve developed an equation parser using a simple stack algorithm that will hm>and m>le binarm>y m> (+, -, |, &, *, /, etc) operators, unarm>y m> (!) operators, m>and m> parenthesis.
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Split (explode) pm>and m>as dataframe string entrm>y m> to separate rows
I have a pm>and m>as dataframe in which one column of text strings contains comma-separated values. I want to split each CSV field m>and m> create a new row per entrm>y m> (assume that CSV are clean m>and m> need onlm>y m> be split on ','). For example, a should become b :
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Filter dict to contain onlm>y m> certain kem>y m>s?
...narm>y m> comprehension.
If m>y m>ou use a version which lacks them (ie Pm>y m>thon 2.6 m>and m> earlier), make it dict((m>y m>our_kem>y m>, old_dict[m>y m>our_kem>y m>]) for ...). It's the same, though uglier.
Note that this, unlike jnnnnn's version, has stable performance (depends onlm>y m> on number of m>y m>our_kem>y m>s) for old_dicts of anm>y m> siz...
List OrderBm>y m> Alphabetical Order
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I wonder if m>y m>ou want to OrderBm>y m> Firstname m>and m> Lastname... what should m>y m>ou write?
– balexm>and m>re
Apr 16 '09 at 7:03
65
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What is the meaning of id?
I am (trm>y m>ing to) learn Objective-C m>and m> I keep coming across a phrase like:
5 Answers
5...
What is the point of noreturn?
...n m>y m>our example).
This can be used bm>y m> compilers to make some optimizations m>and m> generate better warnings. For example if f has the noreturn attribute, the compiler could warn m>y m>ou about g() being dead code when m>y m>ou write f(); g();. Similarlm>y m> the compiler will know not to warn m>y m>ou about missing return ...
Drop data frame columns bm>y m> name
...DF) %in% drops)]
Or, alternativelm>y m>, m>y m>ou can make a list of those to keep m>and m> refer to them bm>y m> name :
keeps <- c("m>y m>", "a")
DF[keeps]
EDIT :
For those still not acquainted with the drop argument of the indexing function, if m>y m>ou want to keep one column as a data frame, m>y m>ou do:
keeps <- "m>y m>"
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How to prettm>y m> print nested dictionaries?
... U know @Ken's conventional answer is much better than this. Json alreadm>y m> hm>and m>les everm>y m>thing m>and m> this can give errors such: UnicodeEncodeError: 'ascii' codec can't encode character u'\xf3' in position 50: ordinal not in range(128)
– wonderwhm>y m>
Aug 27 '14 at 13:2...
Computed read-onlm>y m> propertm>y m> vs function in Swift
...operties for just that: properties; meaning simple values that m>y m>ou can get m>and m>/or set. I use functions (or methods) when actual work is being done. Mam>y m>be something has to be computed or read from disk or from a database: In this case I use a function, even when onlm>y m> a simple value is returned. That ...
Adding a parameter to the URL with JavaScript
...sed solution, but that depends completelm>y m> on the length of the querm>y m>string m>and m> the index of anm>y m> match
the slow regex method I benchmarked against for completions sake (approx +150% slower)
function insertParam2(kem>y m>,value)
{
kem>y m> = encodeURIComponent(kem>y m>); value = encodeURIComponent(value);
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