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How to change a nullable column to not nullable in a Rails migration?
...s:
# Make sure no null value exist
MyModel.where(date_column: nil).update_all(date_column: Time.now)
# Change the column to not allow null
change_column :my_models, :date_column, :datetime, null: false
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How to split text without spaces into list of words?
...el the distribution of the output. A good first approximation is to assume all words are independently distributed. Then you only need to know the relative frequency of all words. It is reasonable to assume that they follow Zipf's law, that is the word with rank n in the list of words has probabilit...
Seeking clarification on apparent contradictions regarding weakly typed languages
...xamples of programming languages that simply coerce/convert types automatically.
9 Answers
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Avoid trailing zeroes in printf()
...ing your number is in the variable num, the following function will remove all but the first N decimals, then strip off the trailing zeros (and decimal point if they were all zeros).
char str[50];
sprintf (str,"%.20g",num); // Make the number.
morphNumericString (str, 3);
: :
void morphNumericS...
Set Locale programmatically
...ocale to the front of the list set.add(locale); LocaleList all = LocaleList.getDefault(); for (int i = 0; i < all.size(); i++) { // append other locales supported by the user set.add(all.get(i)); } Locale[] locales = set.toArray(new ...
Conceptually, how does replay work in a game?
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I think your initial thought was correct. To create a replay, you store all input received from the user (along with the frame number at which it was received) along with the initial seeds of any random number generators. To replay the game, you reset your PRNGs using the saved seeds and feed th...
What are all the escape characters?
I know some of the escape characters in Java, e.g.
4 Answers
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How to add Google Analytics Tracking ID to GitHub Pages
... I have added them, however Google analytics say the Tracking is not installed. My page as specified in G-Analytics is http://avi-aryan.github.io
– Avi
Jul 15 '13 at 12:33
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Example for boost shared_mutex (multiple reads/one write)?
I have a multithreaded app that has to read some data often, and occasionally that data is updated. Right now a mutex keeps access to that data safe, but it's expensive because I would like multiple threads to be able to read simultaneously, and only lock them out when an update is needed (the updat...
How to grep Git commit diffs or contents for a certain word?
In a Git code repository I want to list all commits that contain a certain word. I tried this
8 Answers
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