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Pandas get topmost n records within each group
...
>>> df.groupby('id').head(2)
id value
id
1 0 1 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.gro...
.NET 4.0 has a new GAC, why?
...the new GAC . Does it mean now we have to manage two GACs, one for .NET 2.0-3.5 applications and the other for .NET 4.0 applications?
...
Split a String into an array in Swift?
... like so:
var fullName = "First Last"
var fullNameArr = split(fullName) {$0 == " "}
var firstName: String = fullNameArr[0]
var lastName: String? = fullNameArr.count > 1 ? fullNameArr[1] : nil
with Swift 2
In Swift 2 the use of split becomes a bit more complicated due to the introduction of t...
In-memory size of a Python structure
...gt;>> import decimal
>>>
>>> d = {
... "int": 0,
... "float": 0.0,
... "dict": dict(),
... "set": set(),
... "tuple": tuple(),
... "list": list(),
... "str": "a",
... "unicode": u"a",
... "decimal": decimal.Decimal(0),
... "object": ob...
What is SYSNAME data type in SQL Server?
...
150
sysname is a built in datatype limited to 128 Unicode characters that, IIRC, is used primarily t...
Can I add jars to maven 2 build classpath without installing them?
...
605
Problems of popular approaches
Most of the answers you'll find around the internet will suggest...
Python matplotlib multiple bars
...lotlib.dates import date2num
import datetime
x = [
datetime.datetime(2011, 1, 4, 0, 0),
datetime.datetime(2011, 1, 5, 0, 0),
datetime.datetime(2011, 1, 6, 0, 0)
]
x = date2num(x)
y = [4, 9, 2]
z = [1, 2, 3]
k = [11, 12, 13]
ax = plt.subplot(111)
ax.bar(x-0.2, y, width=0.2, color='b', ...
Java: parse int value from a char
...
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edited Apr 30 '18 at 4:24
Neuron
3,54333 gold badges2323 silver badges4040 bronze badges
a...
How to properly assert that an exception gets raised in pytest?
...est_passes():
with pytest.raises(Exception) as e_info:
x = 1 / 0
def test_passes_without_info():
with pytest.raises(Exception):
x = 1 / 0
def test_fails():
with pytest.raises(Exception) as e_info:
x = 1 / 1
def test_fails_without_info():
with pytest.raises(...
How are booleans formatted in Strings in Python?
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answered Feb 13 '10 at 22:07
danbendanben
70.8k1818 gold badges113113 silver badges140140 bronze badges
...