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Select by partial string from a pandas DataFrame
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Since str.* methods treat the input pattern as a regular expression, you can use df[df['A'].str.contains("Hello|Britain")]
– Garrett
Jun 27 '13 at 19:20
7
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Deep null checking, is there a better way?
...of the language.
Update (2014):
The ?. operator is now planned for the next Roslyn compiler release. Note that there is still some debate over the exact syntactic and semantic analysis of the operator.
Update (July 2015): Visual Studio 2015 has been released and ships with a C# compiler that supp...
Are members of a C++ struct initialized to 0 by default?
...arent p = {}; // value initializes all members
The second will make p.s.{x,y} zero. You cannot use these aggregate initializer lists if you've got constructors in your struct. If that is the case, you will have to add proper initalization to those constructors
struct Snapshot {
int x;
dou...
C/C++ NaN constant (literal)?
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Or you can compare the number to itself – x == x returns false iff x is NaN.
– Archie
May 22 '13 at 12:10
7
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How to avoid scientific notation for large numbers in JavaScript?
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There's Number.toFixed, but it uses scientific notation if the number is >= 1e21 and has a maximum precision of 20. Other than that, you can roll your own, but it will be messy.
function toFixed(x) {
if (Math.abs(x) < 1.0) {
var e ...
How do I create an empty array/matrix in NumPy?
I can't figure out how to use an array or matrix in the way that I would normally use a list. I want to create an empty array (or matrix) and then add one column (or row) to it at a time.
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How do you bind an Enum to a DropDownList control in ASP.NET?
...w ListItem(itemNames(i), itemValues(i))
dropdownlist.Items.Add(item)
Next
Or the same in C#
Array itemValues = System.Enum.GetValues(typeof(Response));
Array itemNames = System.Enum.GetNames(typeof(Response));
for (int i = 0; i <= itemNames.Length - 1 ; i++) {
ListItem item = new Li...
How to use Boost in Visual Studio 2010
What is a good step by step explanation on how to use the Boost library in an empty project in Visual Studio?
13 Answers
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How to declare variable and use it in the same Oracle SQL script?
... a bind variable. The mechanism for assigning values to a VAR is with an EXEC call:
SQL> var name varchar2(20)
SQL> exec :name := 'SALES'
PL/SQL procedure successfully completed.
SQL> select * from dept
2 where dname = :name
3 /
DEPTNO DNAME LOC
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pandas: How do I split text in a column into multiple rows?
I'm working with a large csv file and the next to last column has a string of text that I want to split by a specific delimiter. I was wondering if there is a simple way to do this using pandas or python?
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