大约有 38,970 项符合查询结果（耗时：0.0626秒） [XML]
A semantics for Bash scripts?
...
answered Apr 21 '14 at 23:59
kojirokojiro
65.1k1414 gold badges110110 silver badges168168 bronze badges
...
Remove all the elements that occur in one list from another
...
526
Python has a language feature called List Comprehensions that is perfectly suited to making th...
What is the proper declaration of main?
...
5 Answers
5
Active
...
Determine the data types of a data frame's columns
...is makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
@Wilmer E Henao H's solution is very streamlined:
sapply(my.data, class)
...
Python csv string to array
... StringIO
import csv
scsv = """text,with,Polish,non-Latin,letters
1,2,3,4,5,6
a,b,c,d,e,f
gęś,zółty,wąż,idzie,wąską,dróżką,
"""
f = StringIO(scsv)
reader = csv.reader(f, delimiter=',')
for row in reader:
print('\t'.join(row))
simpler version with split() on newlines:
reader = csv...
Pointers vs. values in parameters and return values
...
twotwotwotwotwotwo
21.2k55 gold badges5959 silver badges5151 bronze badges
...
in iPhone App How to detect the screen resolution of the device
...
350
CGRect screenBounds = [[UIScreen mainScreen] bounds];
That will give you the entire screen's ...
Is it possible to implement a Python for range loop without an iterator variable?
...
for i in xrange(n): f()
loop(lambda: <insert expression here>, 5)
But I think you can just live with the extra i variable.
Here is the option to use the _ variable, which in reality, is just another variable.
for _ in range(n):
do_something()
Note that _ is assigned the last re...
how to return index of a sorted list? [duplicate]
...ed items in the list. For example, if the list I want to sort is [2,3,1,4,5] , I need [2,0,1,3,4] to be returned.
7 Ans...