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Rails migration: t.references with alternative name?
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You can do this all in the initial migration/column definition (at least currently in Rails 5):
t.references :transferable_as, index: true, foreign_key: {to_table: :courses}
t.references :same_as, index: true, foreign_key: {to_table: :cours...
Google Maps: how to get country, state/province/region, city given a lat/long value?
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What you are looking for is called reverse geocoding. Google provides a server-side reverse geocoding service through the Google Geocoding API, which you should be able to use for your project.
This is how a response to the following request would look ...
Why do I get TypeError: can't multiply sequence by non-int of type 'float'?
...hat everyone here talked about multiplying a float with a string (but here all my element were floats all along) so the problem was actually using the * operator on a list.
For example:
import math
import numpy as np
alpha = 0.2
beta=1-alpha
C = (-math.log(1-beta))/alpha
coff = [0.0,0.01,0.0,0.3...
Eclipse comment/uncomment shortcut?
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Use
Ctrl + SHIFT + L which will open a list of all major shortcuts for eclipse.
For single line java code comment and uncomment : Ctrl + / (Forward
Slash)
For multiple line java code comment : Ctrl + Shift +
/ (Forward Slash) and
Multiline uncomment : Ctrl + Shift +
\ ...
Multiplication on command line terminal
...ered Jun 14 '12 at 19:29
We Are All MonicaWe Are All Monica
11.3k77 gold badges3939 silver badges6767 bronze badges
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Changing the status bar text color in splash screen iOS 7
...some stackoverflow questions that say how to change the status bar for all view controllers. I am currently changing the color of status bar this way:
...
Getting exact error type in from DbValidationException
...ity.Validation.DbEntityValidationResult} which gives me no information at all about what field it was unable to initialize.
Is there a way to get more info about this error?
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Check whether a string matches a regex in JS
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Use regex.test() if all you want is a boolean result:
console.log(/^([a-z0-9]{5,})$/.test('abc1')); // false
console.log(/^([a-z0-9]{5,})$/.test('abc12')); // true
console.log(/^([a-z0-9]{5,})$/.test('abc123')); // true
...and ...
Why is document.body null in my javascript?
...body hasn't been defined at this point yet. In general, you want to create all elements before you execute javascript that uses these elements. In this case you have some javascript in the head section that uses body. Not cool.
You want to wrap this code in a window.onload handler or place it after...
How is mime type of an uploaded file determined by browser?
...dden), and then if not found there, we defer to the system registry.
// Finally, we scan a secondary hard-coded list to catch types that we can
// deduce but that we also want to allow the OS to override.
The hard-coded lists come a bit earlier in the file: https://cs.chromium.org/chromium/src/net/...