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Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
Find size of Git repository
...nt ideas of "complete size" you could use:
git bundle create tmp.bundle --all
du -sh tmp.bundle
Close (but not exact:)
git gc
du -sh .git/
With the latter, you would also be counting:
hooks
config (remotes, push branches, settings (whitespace, merge, aliases, user
details etc.)
stashes (see ...
What is __gxx_personality_v0 for?
... quick grep of the libstd++ code base revealed the following two usages of __gx_personality_v0:
In libsupc++/unwind-cxx.h
// GNU C++ personality routine, Version 0.
extern "C" _Unwind_Reason_Code __gxx_personality_v0
(int, _Unwind_Action, _Unwind_Exceptio...
What is the default height of UITableViewCell?
... this out already, but the 1px separator is included in the height. It actually covers the bottom-most content of the cell.
– Ben S
Jan 6 '11 at 20:10
...
Splitting string into multiple rows in Oracle
...ct 108 Name, 'test' Project, 'Err1, Err2, Err3' Error from dual
union all
select 109, 'test2', 'Err1' from dual
)
select distinct
t.name, t.project,
trim(regexp_substr(t.error, '[^,]+', 1, levels.column_value)) as error
from
temp t,
table(cast(multiset(select level from dual conne...
Multiple columns index when using the declarative ORM extension of sqlalchemy
...e just Column objects, index=True flag works normally:
class A(Base):
__tablename__ = 'table_A'
id = Column(Integer, primary_key=True)
a = Column(String(32), index=True)
b = Column(String(32), index=True)
if you'd like a composite index, again Table is present here as usual you ju...
Center HTML Input Text Field Placeholder
...
input{
text-align:center;
}
is all you need.
Working example in FF6. This method doesn't seem to be cross-browser compatible.
Your previous CSS was attempting to center the text of an input element which had a class of "placeholder".
...
C# 4.0 optional out/ref arguments
Does C# 4.0 allow optional out or ref arguments?
9 Answers
9
...
Difference between std::result_of and decltype
...
result_of was introduced in Boost, and then included in TR1, and finally in C++0x. Therefore result_of has an advantage that is backward-compatible (with a suitable library).
decltype is an entirely new thing in C++0x, does not restrict only to return type of a function, and is a language fe...
List directory in Go
... of everything in the current directory (folders are included but not specially marked - you can check if an item is a folder by using the IsDir() method):
package main
import (
"fmt"
"io/ioutil"
"log"
)
func main() {
files, err := ioutil.ReadDir("./")
if err != nil {
...