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How to determine whether a Pandas Column contains a particular value
...s in the index:
In [11]: s = pd.Series(list('abc'))
In [12]: s
Out[12]:
0 a
1 b
2 c
dtype: object
In [13]: 1 in s
Out[13]: True
In [14]: 'a' in s
Out[14]: False
One option is to see if it's in unique values:
In [21]: s.unique()
Out[21]: array(['a', 'b', 'c'], dtype=object)
In [22]:...
How do I use vi keys in ipython under *nix?
...
In case someone's wandering in here recently, IPython 5.0 switched from readline to prompt_toolkit, so an updated answer to this question is to pass an option:
$ ipython --TerminalInteractiveShell.editing_mode=vi
... or to set it globally in the profile configuration (~/.ipytho...
Replacing some characters in a string with another character
...
340
echo "$string" | tr xyz _
would replace each occurrence of x, y, or z with _, giving A__BC___D...
How to assign colors to categorical variables in ggplot2 that have stable mapping?
...al colour scale as follows:
#Some test data
dat <- data.frame(x=runif(10),y=runif(10),
grp = rep(LETTERS[1:5],each = 2),stringsAsFactors = TRUE)
#Create a custom color scale
library(RColorBrewer)
myColors <- brewer.pal(5,"Set1")
names(myColors) <- levels(dat$grp)
colScale <- sc...
How do I select a merge strategy for a git rebase?
...
answered Nov 25 '10 at 3:11
iCrazyiCrazy
2,37611 gold badge1212 silver badges44 bronze badges
...
How to concatenate two IEnumerable into a new IEnumerable?
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answered Jan 4 '13 at 21:07
Jon SkeetJon Skeet
1210k772772 gold badges85588558 silver badges88218821 bronze badges
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MySQL: Insert record if not exists in table
...tnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
SELECT * FROM `table_listnames`;
+----+------...
SignalR - Sending a message to a specific user using (IUserIdProvider) *NEW 2.0.0*
...This depends on how you identify a user in your application.
In SignalR 2.0, this is done by using the inbuilt IPrincipal.Identity.Name, which is the logged in user identifier as set during the ASP.NET authentication.
However, you may need to map the connection with the user using a different iden...
How to verify that method was NOT called in Moq?
...
answered Feb 11 '09 at 16:13
Dan FishDan Fish
2,24211 gold badge1414 silver badges88 bronze badges
...
Why does PostgreSQL perform sequential scan on indexed column?
...
If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the index, then retrieve the row from the heap...