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Rails: Using greater than/less than with a where statement
...th dates here on SO.
>= vs >
To avoid people having to dig through and follow the comments conversation here are the highlights.
The method above only generates a >= query and not a >. There are many ways to handle this alternative.
For discrete numbers
You can use a number_you_want...
How can I strip first X characters from string using sed?
... a small industrial box. I have a variable containing the text pid: 1234 and I want to strip first X characters from the line, so only 1234 stays. I have more variables I need to "clean", so I need to cut away X first characters and ${string:5} doesn't work for some reason in my system.
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How do I sort strings alphabetically while accounting for value when a string is numeric?
I'm trying to sort an array of numbers that are strings and I'd like them to sort numerically.
19 Answers
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get NSDate today, yesterday, this Week, last Week, this Month, last Month… variables
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Adapted from the Date and Time Programming Guide:
// Right now, you can remove the seconds into the day if you want
NSDate *today = [NSDate date];
// All intervals taken from Google
NSDate *yesterday = [today dateByAddingTimeInterval: -86400.0];...
How do I parse a string with a decimal point to a double?
... XmlConvert class ... do you have any ideas whether this is better, worse, and/or different than using CultureInfo.InvariantCulture?
– ChrisW
Aug 30 '09 at 21:23
1
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Why does integer overflow on x86 with GCC cause an infinite loop?
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When the standard says it's undefined behavior, it means it. Anything can happen. "Anything" includes "usually integers wrap around, but on occasion weird stuff happens".
Yes, on x86 CPUs, integers usually wrap the way you expect. This...
What is a Proxy in Doctrine 2?
... just finished reading all the Doctrine 2 documentation, I started my own sandbox, I understood most of the principes, but there is still a question and I couldn't find any complete explanation in the doc.
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Best way to check if object exists in Entity Framework?
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if (context.MyEntity.Any(o => o.Id == idToMatch))
{
// Match!
}
And in vb.net
If context.MyEntity.Any(function(o) o.Id = idToMatch) Then
' Match!
End If
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Listing only directories using ls in Bash?
This command lists directories in the current path: ls -d */
26 Answers
26
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Selecting data frame rows based on partial string match in a column
...a data.table (but also remember that subsetting approaches for data.frames and data.tables are not identical):
library(data.table)
mtcars[rownames(mtcars) %like% "Merc", ]
iris[iris$Species %like% "osa", ]
If that is what you had, then perhaps you had just mixed up row and column positions for su...