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Get column index from column name in python pandas
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Sure, you can use .get_loc():
In [45]: df = DataFrame({"pear": [1,2,3], "apple": [2,3,4], "orange": [3,4,5]})
In [46]: df.columns
Out[46]: Index([apple, orange, pear], dtype=object)
In [47]: df.columns.get_loc("pear")
Out[47]: 2
although to be honest I do...
LINQ where vs takewhile
...ind all elements matching the condition
var intList = new int[] { 1, 2, 3, 4, 5, -1, -2 };
Console.WriteLine("Where");
foreach (var i in intList.Where(x => x <= 3))
Console.WriteLine(i);
Console.WriteLine("TakeWhile");
foreach (var i in intList.TakeWhile(x => x <= 3))
Console.Wri...
Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
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147
Update
data.table v1.9.6+ now supports OP's original attempt and the following answer is no lon...
python tuple to dict
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answered Sep 24 '10 at 1:07
Greg HewgillGreg Hewgill
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Time complexity of Sieve of Eratosthenes algorithm
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4 Answers
4
Active
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How to remove last n characters from every element in the R vector
..._bar","bar_foo","apple","beer")
a = data.frame("data"=char_array,"data2"=1:4)
a$data = substr(a$data,1,nchar(a$data)-3)
a should now contain:
data data2
1 foo_ 1
2 bar_ 2
3 ap 3
4 b 4
share
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What is IP address '::1'?
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BradBrad
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Select statement to find duplicates on certain fields
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840
To get the list of fields for which there are multiple records, you can use..
select field1,fie...
jQuery map vs. each
...u can potentially waste a lot of memory.
For example:
var items = [1,2,3,4];
$.each(items, function() {
alert('this is ' + this);
});
var newItems = $.map(items, function(i) {
return i + 1;
});
// newItems is [2,3,4,5]
You can also use the map function to remove an item from an array. For...
Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
...t how the + operator behaves in general also.
So, here it goes.
Excluding E4X and implementation-specific stuff, Javascript (as of ES5) has 6 built-in data types:
Undefined
Null
Boolean
Number
String
Object
Note that although typeof somewhat confusingly returns object for Null and function for cal...