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How do you create a yes/no boolean field in SQL server?
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The equivalent is a BIT field.
In SQL you use 0 and 1 to set a bit field (just as a yes/no field in Access). In Management Studio it displays as a false/true value (at least in recent versions).
When accessing the database through ASP.NET it will expose the field as a b...
In C++, is it still bad practice to return a vector from a function?
...arrays—in many programming languages. Is this style now acceptable in C++0x if the class has a move constructor, or do C++ programmers consider it weird/ugly/abomination?
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Remove duplicated rows using dplyr
...r below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data fr...
How to format numbers by prepending 0 to single-digit numbers?
I want to format a number to have two digits. The problem is caused when 0 – 9 is passed, so I need it to be formatted to 00 – 09 .
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How to create an array containing 1…N
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409
If I get what you are after, you want an array of numbers 1..n that you can later loop through....
Logical operators for boolean indexing in Pandas
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When you say
(a['x']==1) and (a['y']==10)
You are implicitly asking Python to convert (a['x']==1) and (a['y']==10) to boolean values.
NumPy arrays (of length greater than 1) and Pandas objects such as Series do not have a boolean value -- in other words, they ...
Matplotlib tight_layout() doesn't take into account figure suptitle
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10 Answers
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Replacing NAs with latest non-NA value
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divibisan
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answered Oct 12 '11 at 5:32
Dirk EddelbuettelDir...
Zero-pad digits in string
I need to cast single figures (1 to 9) to (01 to 09). I can think of a way but its big and ugly and cumbersome. I'm sure there must be some concise way. Any Suggestions
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How do you plot bar charts in gnuplot?
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Simple bar graph:
set boxwidth 0.5
set style fill solid
plot "data.dat" using 1:3:xtic(2) with boxes
data.dat:
0 label 100
1 label2 450
2 "bar label" 75
If you want to style your bars differently, you can do something like:
set style lin...