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Get the real width and height of an image with JavaScript? (in Safari/Chrome)
...eady finished downloading. If the image is not cached or if this code is called before window.onload, a height/width of 0 might be returned. In any case, I've integrated FDisk's idea into the solution above.
– Xavi
Feb 10 '11 at 2:26
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Add new column with foreign key constraint in one command
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As so often with SQL-related question, it depends on the DBMS. Some DBMS allow you to combine ALTER table operations separated by commas. For example...
Informix syntax:
ALTER TABLE one
ADD two_id INTEGER,
ADD CONSTRAINT FOREIGN KEY(two_id) REFERENCES two(id);
The syntax for IBM DB2 LU...
How to get .app file of a xcode application
... friend to use that application. From where do I get this file? How to install this .app file in his Applications folder using an installer package?
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How do I call a JavaScript function on page load?
Traditionally, to call a JavaScript function once the page has loaded, you'd add an onload attribute to the body containing a bit of JavaScript (usually only calling a function)
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Distinct in Linq based on only one field of the table
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MoreLinq has a DistinctBy method that you can use:
It will allow you to do:
var results = table1.DistictBy(row => row.Text);
The implementation of the method (short of argument validation) is as follows:
private static IEnumerable<TSource> DistinctByImpl<TSource, TKey...
How do I unlock a SQLite database?
... that page is either incorrect or out-of-date: I have a process doing literally nothing but a single INSERT that is getting that locked message: it is not possible for this process to have caused the lock. The problem was in another process talking to the same DB.
– Dan James...
Changing navigation bar color in Swift
I am using a Picker View to allow the user to choose the colour theme for the entire app.
30 Answers
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Can a recursive function be inline?
...torial(x3 - 1);
}
}
}
}
In this case, we've basically inlined the function 3 times. Some compilers do perform this optimization. I recall MSVC++ having a setting to tune the level of inlining that would be performed on recursive functions (up to 20, I believe).
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How to select the row with the maximum value in each group
...ata.table) ## 1.9.2
group <- as.data.table(group)
If you want to keep all the entries corresponding to max values of pt within each group:
group[group[, .I[pt == max(pt)], by=Subject]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: 2 17 2
# 3: 3 5 2
If you'd like ju...
No Persistence provider for EntityManager named
...name using TopLink under the META-INF directory.
Then, I have my code calling it with:
30 Answers
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