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How can I check for NaN values?
float('nan') results in Nan (not a number). But how do I check for it? Should be very easy, but I cannot find it.
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mysql update column with value from another table
...for example:
UPDATE tableB
INNER JOIN tableA ON tableB.name = tableA.name
SET tableB.value = IF(tableA.value > 0, tableA.value, tableB.value)
WHERE tableA.name = 'Joe'
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Why is processing a sorted array faster than processing an unsorted array?
...u stop the train to ask the driver which direction they want. And then you set the switch appropriately.
Trains are heavy and have a lot of inertia. So they take forever to start up and slow down.
Is there a better way? You guess which direction the train will go!
If you guessed right, it continues...
Best practices for SQL varchar column length [closed]
Every time is set up a new SQL table or add a new varchar column to an existing table, I am wondering one thing: what is the best value for the length .
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Null vs. False vs. 0 in PHP
...eal with states:
You want to make a difference between DebugMode = False (set to off), DebugMode = True (set to on) and DebugMode = Null (not set at all, will lead to hard debugging ;-)).
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Updating packages in Emacs
I have the following setup for packages (not sure if there is a better recommended one):
4 Answers
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What's the difference between “squash” and “fixup” in Git/Git Extension?
...ve commit
# l, label <label> = label current HEAD with a name
# t, reset <label> = reset HEAD to a label
# m, merge [-C <commit> | -c <commit>] <label> [# <oneline>]
# . create a merge commit using the original merge commit's
# . message (or the onelin...
Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
This is an interview question from google. I am not able to solve it by myself. Can somebody shed some light?
14 Answers
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Rails: redirect_to with :error, but flash[:error] empty
I'm trying to do a redirect while setting the flash[:error] value. (Rails 3.0.10)
3 Answers
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how do I insert a column at a specific column index in pandas?
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