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Return multiple columns from pandas apply()
...ed to supply it with pd.Series(data, index=...). Otherwise you get cryptic errors when you try to assign the result back into the parent dataframe.
– smci
Nov 25 '19 at 11:05
...
Most efficient way to determine if a Lua table is empty (contains no entries)?
... the context of lua 5.2 & 5.3, is that non locals are either upvals or _ENV lookups. An upval has to go through an extra layer of indirection, whereas an _ENV lookup is a table lookup. Whereas a local is a register in the VM
– Demur Rumed
Jul 28 '17 at 0:30...
Select count(*) from multiple tables
...
Just because it's slightly different:
SELECT 'table_1' AS table_name, COUNT(*) FROM table_1
UNION
SELECT 'table_2' AS table_name, COUNT(*) FROM table_2
UNION
SELECT 'table_3' AS table_name, COUNT(*) FROM table_3
It gives the answers transposed (one row per table instead of ...
Unit testing that events are raised in C# (in order)
...n, you can easily extend your existing test:
[TestMethod]
public void Test_ThatMyEventIsRaised()
{
List<string> receivedEvents = new List<string>();
MyClass myClass = new MyClass();
myClass.PropertyChanged += delegate(object sender, PropertyChangedEventArgs e)
{
...
How stable is the git plugin for eclipse?
...t with completely different GUI, unheard commands, two or even single word error messages and "features" like overwriting the shared repository without warning? Do not use it, use command line interface. If you do not like command line interface, do not use GIT at all.
...
How to assign colors to categorical variables in ggplot2 that have stable mapping?
...er.pal(5,"Set1")
names(myColors) <- levels(dat$grp)
colScale <- scale_colour_manual(name = "grp",values = myColors)
and then add the color scale onto the plot as needed:
#One plot with all the data
p <- ggplot(dat,aes(x,y,colour = grp)) + geom_point()
p1 <- p + colScale
#A second plo...
How to show all shared libraries used by executables in Linux?
... will look something like this:
1 /lib64/libexpat.so.0
1 /lib64/libgcc_s.so.1
1 /lib64/libnsl.so.1
1 /lib64/libpcre.so.0
1 /lib64/libproc-3.2.7.so
1 /usr/lib64/libbeecrypt.so.6
1 /usr/lib64/libbz2.so.1
1 /usr/lib64/libelf.so.1
1 /usr/lib64/libpopt.so.0
1 /usr/lib64/librpm-4.4.so...
Group By Multiple Columns
...
in case of mvc with nHibernate getting error for dll issues. Problem resolved by GroupBy(x=> new { x.Column1, x.Column2 }, (key, group) => new { Key1 = key.Column1, Key2 = key.Column2 , Result = ...
How can a LEFT OUTER JOIN return more records than exist in the left table?
...
Table1 Table2
_______ _________
1 2
2 2
3 5
4 6
SELECT Table1.Id, Table2.Id FROM Table1 LEFT OUTER JOIN Table2 ON Table1.Id=Table2.Id
Resu...
How can I connect to MySQL in Python 3 on Windows?
...verything seemed fine. Until I tried connecting to a database, and got "KeyError [56]". An error which I was unable to find documented anywhere.
So I gave up on pymysql, and I settled on the Oracle MySQL connector.
It comes as a setup package, and works out of the box. And it also seems decently d...