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Creating dataframe from a dictionary where entries have different lengths
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In Python 3.x:
import pandas as pd
import numpy as np
d = dict( A = np.array([1,2]), B = np.array([1,2,3,4]) )
pd.DataFrame(dict([ (k,pd.Series(v)) for k,v in d.items() ]))
Out[7]:
A B
0 1 1
1 2 2
2 NaN 3
3 NaN 4
In Python 2.x...
Going to a specific line number using Less in Unix
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... and don't hit enter after g, or you will jump one further line.
– HongboZhu
Jan 14 at 11:28
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How do I alter the position of a column in a PostgreSQL database table?
...e column order is either by
recreating the table, or by adding
columns and rotating data until you
reach the desired layout.
That's pretty weak, but in their defense, in standard SQL, there is no solution for repositioning a column either. Database brands that support changing the ordinal p...
Insert Update stored proc on SQL Server
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Your assumption is right, this is the optimal way to do it and it's called upsert/merge.
Importance of UPSERT - from sqlservercentral.com:
For every update in the case mentioned above we are removing one
additional read from the table if we
use the UPSERT instead of EXISTS....
What's the fastest way to convert String to Number in JavaScript?
...fastest for Number() in Chrome 37.0.2062.124 on Windows Server 2008 R2 / 7 and ParseInt() in Firefox 30.0 with implicit being the slowest for both. Also, you might consider including string literal floats in the test for general comparison. My guess is that it may change the order in some cases be...
How to change SmartGit's licensing option after 30 days of commercial use on ubuntu?
...ensing option, because I was just clicking "next" button : ) (30 day trial and then you have to buy it). Now today is my 31st day of using SG and I can't change my licensing options (reinstalling smartgit doesn't help) and I'm not able to use SG anymore without paying (I'm not using it for commercia...
Round a double to 2 decimal places [duplicate]
... too.
So, use this instead
(Adapted from this answer by Louis Wasserman and this one by Sean Owen.)
public static double round(double value, int places) {
if (places < 0) throw new IllegalArgumentException();
BigDecimal bd = BigDecimal.valueOf(value);
bd = bd.setScale(places, Rou...
How long should SQL email fields be? [duplicate]
...dress field is going to be arbitrary. However, I was wondering what the "standard" is? How long do you guys make it? (same question for Name field...)
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HTTP 401 - what's an appropriate WWW-Authenticate header value?
...ke:
WWW-Authenticate: Basic realm="myRealm"
Whereas Basic is the scheme and the remainder is very much dependent on that scheme. In this case realm just provides the browser a literal that can be displayed to the user when prompting for the user id and password.
You're obviously not using Basic ...
ERROR 1130 (HY000): Host '' is not allowed to connect to this MySQL server [duplicate]
...
Your root account, and this statement applies to any account, may only have been added with localhost access (which is recommended).
You can check this with:
SELECT host FROM mysql.user WHERE User = 'root';
If you only see results with loca...