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Difference between float and decimal data type
...mysql> insert into numbers values (100, 100);
mysql> select @a := (a/3), @b := (b/3), @a * 3, @b * 3 from numbers \G
*************************** 1. row ***************************
@a := (a/3): 33.333333333
@b := (b/3): 33.333333333333
@a + @a + @a: 99.999999999000000000000000000000
@b + @b...
Cannot ping AWS EC2 instance
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answered May 30 '15 at 9:39
RakibRakib
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How can I disable logging of asset pipeline (sprockets) messages in Ruby on Rails 3.1?
... tends to be quite verbose in the (dev) log by default under Ruby on Rails 3.1 (RC1):
14 Answers
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Cannot import XSSF in Apache POI
I am referencing the version 3.7 of the Apache POI and I am getting a "cannot be resolved" error when I do:
11 Answers
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Oracle JDBC ojdbc6 Jar as a Maven Dependency
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13 Answers
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[A]System.Web.WebPages.Razor.Configuration.HostSection cannot be cast to… web.config issue
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I am using VS2013, MVC 5.2.2.0, Web Api 2. I have just changed the all versions from 2.0.0.0 to 3.0.0.0 of the following section of Web.config resides inside the View folder of my project.
<configSections>
<sectionGroup name="syste...
bundle install fails with SSL certificate verification error
When I run bundle install for my Rails 3 project on Centos 5.5 it fails with an error:
28 Answers
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Replace all 0 values to NA
...me space for it. E.g.,
data.frame(x = c(1, NA, 2))
# x
# 1 1
# 2 NA
# 3 2
Also, the data frame structure requires all the columns to have the same number of elements so that there can be no "holes" (i.e., NULL values).
Now you could replace zeroes by NULL in a data frame in the sense of com...
Removing numbers from string [closed]
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edited Oct 12 '12 at 3:54
answered Oct 12 '12 at 3:34
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The 'json' native gem requires installed build tools
I have ruby 1.9.2p180 (2011-02-18) [i386-mingw32] installed on my windows 7 machine. Now I tried to install the JSON gem using the command, "gem install json" and got the following error.
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