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Find indices of elements equal to zero in a NumPy array
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228
numpy.where() is my favorite.
>>> x = numpy.array([1,0,2,0,3,0,4,5,6,7,8])
>>&...
How to compare times in Python?
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132
You can't compare a specific point in time (such as "right now") against an unfixed, recurring e...
mysql :: insert into table, data from another table?
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INSERT INTO action_2_members (campaign_id, mobile, vote, vote_date)
SELECT campaign_id, from_number, received_msg, date_received
FROM `received_txts`
WHERE `campaign_id` = '8'
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How would I get a cron job to run every 30 minutes?
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edited Sep 27 '11 at 13:45
Tim Cooper
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Active Record - Find records which were created_at before today
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Using ActiveRecord the standard way:
MyModel.where("created_at < ?", 2.days.ago)
Using the underlying Arel interface:
MyModel.where(MyModel.arel_table[:created_at].lt(2.days.ago))
Using a thin layer over Arel:
MyModel.where(MyModel[:created_at] < 2.days.ago)
Using squeel:
MyModel.w...
Suppress command line output
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212
Because error messages often go to stderr not stdout.
Change the invocation to this:
taskkil...
“Insert if not exists” statement in SQLite
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edited Apr 13 '18 at 6:12
answered Oct 12 '13 at 17:38
Cy...
What's the difference between `1L` and `1`?
I often seen the symbol 1L (or 2L , 3L , etc) appear in R code. Whats the difference between 1L and 1 ? 1==1L evaluates to TRUE . Why is 1L used in R code?
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