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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 don't often need this myself. U...
LINQ where vs takewhile
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159
TakeWhile stops when the condition is false, Where continues and find all elements matching th...
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 lo...
python tuple to dict
For the tuple, t = ((1, 'a'),(2, 'b'))
dict(t) returns {1: 'a', 2: 'b'}
6 Answers
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Time complexity of Sieve of Eratosthenes algorithm
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118
Your n/2 + n/3 + n/5 + … n/97 is not O(n), because the number of terms is not constant. [Ed...
How to remove last n characters from every element in the R vector
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117
Here is an example of what I would do. I hope it's what you're looking for.
char_array = c("...
What is IP address '::1'?
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152
::1 is the loopback address in IPv6. Think of it as the IPv6 version of 127.0.0.1.
See http:...
Select statement to find duplicates on certain fields
... of fields for which there are multiple records, you can use..
select field1,field2,field3, count(*)
from table_name
group by field1,field2,field3
having count(*) > 1
Check this link for more information on how to delete the rows.
http://support.microsoft.com/kb/139444
There should be a cr...
jQuery map vs. each
...ion you 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...
Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
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13 Answers
13
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