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E11000 duplicate key error index in mongodb mongoose
...ld in a unique index, the index will store a null value for this document. Because of the unique constraint, MongoDB will only permit one document that lacks the indexed field. If there is more than one document without a value for the indexed field or is missing the indexed field, the index build w...
Reading a UTF8 CSV file with Python
...h accented characters with Python (only French and/or Spanish characters). Based on the Python 2.5 documentation for the csvreader ( http://docs.python.org/library/csv.html ), I came up with the following code to read the CSV file since the csvreader supports only ASCII.
...
matplotlib colorbar for scatter
...
From the matplotlib docs on scatter 1:
cmap is only used if c is an array of floats
So colorlist needs to be a list of floats rather than a list of tuples as you have it now.
plt.colorbar() wants a mappable object, like the CircleCollect...
Why is string concatenation faster than array join?
Today, I read this thread about the speed of string concatenation.
9 Answers
9
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open-ended function arguments with TypeScript
...
The TypeScript way of doing this is to place the ellipsis operator (...) before the name of the argument. The above would be written as,
function sum(...numbers: number[]) {
var aggregateNumber = 0;
for (var i = 0; i < numbers.length; i++)
aggregateNumber += numbers[i];
ret...
How can I use a DLL file from Python?
...mple of ctypes is from actual code I've written (in Python 2.5). This has been, by far, the easiest way I've found for doing what you ask.
import ctypes
# Load DLL into memory.
hllDll = ctypes.WinDLL ("c:\\PComm\\ehlapi32.dll")
# Set up prototype and parameters for the desired function call.
# ...
Interface type check with Typescript
...ceof keyword as you can write custom type guards now:
interface A{
member:string;
}
function instanceOfA(object: any): object is A {
return 'member' in object;
}
var a:any={member:"foobar"};
if (instanceOfA(a)) {
alert(a.member);
}
Lots of Members
If you need to check a lot of mem...
Will GetType() return the most derived type when called from the base class?
Will GetType() return the most derived type when called from the base class?
3 Answers
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Setting DIV width and height in JavaScript
... properties you're using may not work in Firefox, Chrome, and other non-IE browsers. To make this work in all browsers, I also suggest adding the following:
document.getElementById('div_register').setAttribute("style","width:500px");
For cross-compatibility, you will still need to use the propert...
Site stopped working in asp.net System.Web.WebPages.Razor.Configuration.HostSection cannot be cast t
I have a problem like this on server
9 Answers
9
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