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Annotating text on individual facet in ggplot2
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Typically you'd do something like this:
ann_text <- data.frame(mpg = 15,wt = 5,lab = "Text",
cyl = factor(8,levels = c("4","6","8")))
p + geom_text(data = ann_text,label = "Text")
It should work without specifying the factor variable comple...
Pandas - Get first row value of a given column
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To select the ith row, use iloc:
In [31]: df_test.iloc[0]
Out[31]:
ATime 1.2
X 2.0
Y 15.0
Z 2.0
Btime 1.2
C 12.0
D 25.0
E 12.0
Name: 0, dtype: float64
To select the ith value in the Btime column you could use:
In ...
How to use GROUP_CONCAT in a CONCAT in MySQL
...what you need.
Update
Splitting in two steps. First we get a table having all values(comma separated) against a unique[Name,id]. Then from obtained table we get all names and values as a single value against each unique id
See this explained here SQL Fiddle Demo (scroll down as it has two result se...
Equals(=) vs. LIKE
...tify an example where these operators produce obviously different results. Allow me to quote from the MySQL manual:
Per the SQL standard, LIKE performs matching on a per-character basis, thus it can produce results different from the = comparison operator:
mysql> SELECT 'ä' LIKE 'ae' COLLA...
Python nonlocal statement
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@Dustin - Actually, if you had class A with an attribute x and a subclass B defined in it, you would refer to x from within B as A.x
– Anon
Aug 11 '09 at 18:37
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Update multiple columns in SQL
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i think use 1keydata.com/sql/sqlupdate.html "SET column_1 = [value1], column_2 = [value2]"
– DeLe
Jun 9 '13 at 1:01
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Random color generator
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You can remove .split('') call. String already have Array indexer.
– ujeenator
Jul 27 '15 at 6:08
4
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Calling constructors in c++ without new
...d the most common way of creating new dynamic objects instead of using auto_ptr, unique_ptr, or related.
– Fred Nurk
Jan 18 '11 at 13:18
3
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Can I use assert on Android devices?
...t.
You can do
import static junit.framework.Assert.*;
now you can use all the functions like assertTrue, assertEquals, assertNull that are provided in the junit framework.
Be careful not to import the Junit4 framework through eclipse, that would be the org.junit package. You have to use the j...
Understanding typedefs for function pointers in C
...es' code which had typedefs for pointers to functions with arguments. I recall that it took me a while to get around to such a definition while trying to understand a numerical algorithm written in C a while ago. So, could you share your tips and thoughts on how to write good typedefs for pointers t...