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Performing Inserts and Updates with Dapper
...terested in using Dapper - but from what I can tell it only supports Query and Execute. I do not see that Dapper includes a way of Inserting and Updating objects.
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Convert data.frame column format from character to factor
... of the variables (all numeric)
#one approach it to index with the $ sign and the as.factor function
mtcars$am <- as.factor(mtcars$am)
#another approach
mtcars[, 'cyl'] <- as.factor(mtcars[, 'cyl'])
str(mtcars) # now look at the classes
This also works for character, dates, integers and ot...
Install MySQL on Ubuntu without a password prompt
...nk root password.)
If your shell doesn't support here-strings (zsh, ksh93 and bash support them), use:
echo ... | sudo debconf-set-selections
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Need for predictable random generator
I'm a web-game developer and I got a problem with random numbers. Let's say that a player has 20% chance to get a critical hit with his sword. That means, 1 out of 5 hits should be critical. The problem is I got very bad real life results — sometimes players get 3 crits in 5 hits, sometimes none i...
Why don't Java Generics support primitive types?
...as to be convertable to Object (in this example get(0) returns an Object), and the primitive types aren't. So they can't be used in generics.
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Are global variables in PHP considered bad practice? If so, why?
...l way. I generally have a variable that contains the system configuration, and when I nead to access this variable in a function, I do global $var; .
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How to sort an array in descending order in Ruby
...y
require 'benchmark'
ary = []
1000.times {
ary << {:bar => rand(1000)}
}
n = 500
Benchmark.bm(20) do |x|
x.report("sort") { n.times { ary.sort{ |a,b| b[:bar] <=> a[:bar] } } }
x.report("sort reverse") { n.times { ary.sort{ |a,b| a[:bar] <=> b[:bar...
Why no ICloneable?
... answered Feb 11 '09 at 11:16
Andrey ShchekinAndrey Shchekin
19.1k1414 gold badges8585 silver badges142142 bronze badges
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Is the order of elements in a JSON list preserved?
...ed collection of zero or more name/value
pairs, where a name is a string and a value is a string, number,
boolean, null, object, or array.
An array is an ordered sequence of zero or more values.
The terms "object" and "array" come from the conventions of
JavaScript.
Some implementa...
Anonymous recursive PHP functions
Is it possible to have a PHP function that is both recursive and anonymous? This is my attempt to get it to work, but it doesn't pass in the function name.
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