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Update MongoDB field using value of another field
In MongoDB, is it possible to update the value of a field using the value from another field? The equivalent SQL would be something like:
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Formula px to dp, dp to px android
...olved my problem by using the following formulas. May other people benefit from it.
dp to px:
displayMetrics = context.getResources().getDisplayMetrics();
return (int)((dp * displayMetrics.density) + 0.5);
px to dp:
displayMetrics = context.getResources().getDisplayMetrics();
return (int) ((px/...
how does multiplication differ for NumPy Matrix vs Array classes?
... rules of linear algebra
some code snippets to illustrate:
>>> from numpy import linalg as LA
>>> import numpy as NP
>>> a1 = NP.matrix("4 3 5; 6 7 8; 1 3 13; 7 21 9")
>>> a1
matrix([[ 4, 3, 5],
[ 6, 7, 8],
[ 1, 3, 13],
[ 7, 21, 9...
How can I create an object based on an interface file definition in TypeScript?
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Thanks. I was hoping to get away from having to define all of the modal contents initially. Would it be easier if instead of an interface I defined Modal as a class with properties and then used new and a constructor to set up all of the initial values?
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What's the need of array with zero elements?
...ll remain that of the flexible array member, even if this would differ
from that of the replacement array. If this array would have no elements, it behaves as if
it had one element but the behavior is undefined if any attempt is made to access that
element or to generate a pointer one pas...
vector::at vs. vector::operator[]
... code. If you need to bounds-check at runtime because e.g. the index comes from user input, you're indeed best off with an if statement. So in summary, design your code with the intention that vector::at() will never throw an exception, so that if it does, and your program aborts, it's a sign of a b...
Lists in ConfigParser
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There is nothing stopping you from packing the list into a delimited string and then unpacking it once you get the string from the config. If you did it this way your config section would look like:
[Section 3]
barList=item1,item2
It's not pretty but ...
WWW or not WWW, what to choose as primary site name? [closed]
From technical perspective the only issue is traffic and incoming links (one of them should redirect to another).
14 Answe...
Best way to create enum of strings?
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Custom String Values for Enum
from http://javahowto.blogspot.com/2006/10/custom-string-values-for-enum.html
The default string value for java enum is its face value, or the element name. However, you can customize the string value by overriding toString(...
Creating virtual directories in IIS express
...ion. Ex: iisexpress /site:WebSiteWithVirtualDirectory - run the first app from the path "C:\temp\website1". How can i run my the 2nd app that contains the path "d:\temp\SubFolderApp"
– Velu
Aug 29 '12 at 12:00
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