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Apply pandas function to column to create multiple new columns?
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I usually do this using zip:
>>> df = pd.DataFrame([[i] for i in range(10)], columns=['num'])
>>> df
num
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
>>> def powers(x):
>>> return x, x**2, x**3, x**4, x**5, x**6
>>...
How to activate JMX on my JVM for access with jconsole?
How to activate JMX on a JVM for access with jconsole?
11 Answers
11
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Java: random long number in 0
Random class has a method to generate random int in a given range. For example:
16 Answers
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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
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You can use pd.Series.isin.
For "IN" use: something.isin(somewhere)
Or for "NOT IN": ~something.isin(somewhere)
As a worked example:
import pandas as pd
>>> df
country
0 US
1 UK
2 Germany
3 China
>>> countries_to...
How to efficiently concatenate strings in go
...Go 1.10 there is a strings.Builder type, please take a look at this answer for more detail.
Old Way:
Use the bytes package. It has a Buffer type which implements io.Writer.
package main
import (
"bytes"
"fmt"
)
func main() {
var buffer bytes.Buffer
for i := 0; i < 1000; i++...
Ternary operator is twice as slow as an if-else block?
...question, we'll examine the assembly code produced by the X86 and X64 JITs for each of these cases.
X86, if/then
32: foreach (int i in array)
0000007c 33 D2 xor edx,edx
0000007e 83 7E 04 00 cmp dword ptr [esi+4],0
00000082 7E 1C ...
How to set a Default Route (To an Area) in MVC
Ok this has been asked before but there is no solid solution out there. So for purpose of myself and others who may find this useful.
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Deleting all pending tasks in celery / rabbitmq
How can I delete all pending tasks without knowing the task_id for each task?
9 Answers
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C++ auto keyword. Why is it magic?
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auto was a keyword that C++ "inherited" from C that had been there nearly forever, but virtually never used because there were only two possible conditions: either it wasn't allowed, or else it was assumed by default.
The use of auto to mean a deduced type was new with C++11.
At the same time, a...
Matplotlib discrete colorbar
I am trying to make a discrete colorbar for a scatterplot in matplotlib
7 Answers
7
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