大约有 19,000 项符合查询结果（耗时：0.0435秒） [XML]
Get the week start date and week end date from week number
...
Robin DayRobin Day
92.5k2222 gold badges110110 silver badges160160 bronze badges
3
...
Which timestamp type should I choose in a PostgreSQL database?
...ivery schedule because a relative timestamp is immune to Congress’ ill-informed tampering. Where the cutoff between using relative vs absolute times for scheduling things is, is a fuzzy line, but my rule of thumb is that scheduling for anything in the future further than 3-6mo should make use of r...
Which is faster: while(1) or while(2)?
...rt(7);
}
while(x()) {}
At -O0, these two examples actually call x and perform a comparison for each iteration.
First example (returning 1):
.L4:
call x
testl %eax, %eax
jne .L4
movl $0, %eax
addq $32, %rsp
popq %rbp
ret
.seh_endproc
.ident "GCC: (...
How to prevent ifelse() from turning Date objects into numeric objects
...d class of the inputs.
library(data.table)
dates <- fifelse(dates == '2011-01-01', dates - 1, dates)
str(dates)
# Date[1:5], format: "2010-12-31" "2011-01-02" "2011-01-03" "2011-01-04" "2011-01-05"
dplyr::if_else
From dplyr 0.5.0 release notes:
[if_else] have stricter semantics that ifelse():...
data.table vs dplyr: can one do something well the other can't or does poorly?
...nals are in C++ using Rcpp.
The data.table syntax is consistent in its form - DT[i, j, by]. To keep i, j and by together is by design. By keeping related operations together, it allows to easily optimise operations for speed and more importantly memory usage, and also provide some powerful featu...
JavaScript hashmap equivalent
...ion still requires more explanations. Let me clarify the idea in a Q&A form.
Your solution doesn't have a real hash. Where is it???
JavaScript is a high-level language. Its basic primitive (Object) includes a hash table to keep properties. This hash table is usually written in a low-level langua...
Catching an exception while using a Python 'with' statement
...print('__exit__ raised:', err)
Alternative approach using the equivalent form mentioned in PEP 343
PEP 343 -- The "with" Statement specifies an equivalent "non-with" version of the with statement. Here we can readily wrap the various parts with try ... except and thus differentiate between the di...
Filter dataframe rows if value in column is in a set list of values [duplicate]
...9' ... # $ means end of string
... '600141' ...
... '600329' ...
... ... ...
Suppose now we have a list of strings which we want the values in 'STK_ID' to end with, e.g.
endstrings = ['01$', '02$', '05$']
We can join these strings with the regex 'o...
Pass array to ajax request in $.ajax() [duplicate]
....serialize(). There is .serialize() but it's meant to be used on a set of form elements. Try this code and you will only get TypeError: $.serialize is not a function
– billynoah
Aug 5 '17 at 0:52
...
JavaScript function to add X months to a date
...ate.setDate(0);
}
return date;
}
// Add 12 months to 29 Feb 2016 -> 28 Feb 2017
console.log(addMonths(new Date(2016,1,29),12).toString());
// Subtract 1 month from 1 Jan 2017 -> 1 Dec 2016
console.log(addMonths(new Date(2017,0,1),-1).toString());
// Subtract 2 months from...