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python pandas: Remove duplicates by columns A, keeping the row with the highest value in column B
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How do you delete a column by name in data.table?
...of the following will remove column foo from the data.table df3:
# Method 1 (and preferred as it takes 0.00s even on a 20GB data.table)
df3[,foo:=NULL]
df3[, c("foo","bar"):=NULL] # remove two columns
myVar = "foo"
df3[, (myVar):=NULL] # lookup myVar contents
# Method 2a -- A safe idiom for e...
How do you calculate log base 2 in Java for integers?
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What are file descriptors, explained in simple terms?
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What is RSS and VSZ in Linux memory management
... to 2500K of shared libraries, has 200K of stack/heap allocations of which 100K is actually in memory (rest is swapped or unused), and it has only actually loaded 1000K of the shared libraries and 400K of its own binary then:
RSS: 400K + 1000K + 100K = 1500K
VSZ: 500K + 2500K + 200K = 3200K
Since...
How to change the DataTable Column Name?
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edited Jun 21 '11 at 1:11
answered Jun 20 '11 at 5:47
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Responsive iframe using Bootstrap
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Option 1
With Bootstrap 3.2 you can wrap each iframe in the responsive-embed wrapper of your c...
How to put individual tags for a scatter plot
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Object.getOwnPropertyNames vs Object.keys
...ar a = {};
Object.defineProperties(a, {
one: {enumerable: true, value: 1},
two: {enumerable: false, value: 2},
});
Object.keys(a); // ["one"]
Object.getOwnPropertyNames(a); // ["one", "two"]
If you define a property without providing property attributes descriptor (meaning you don't use Obj...
Extract substring in Bash
Given a filename in the form someletters_12345_moreleters.ext , I want to extract the 5 digits and put them into a variable.
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