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How to save and restore multiple different sessions in Vim?
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14 Answers
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What is a stack trace, and how can I use it to debug my application errors?
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In simple terms, a stack trace is a list of the method calls that the application was in the mi...
Android- create JSON Array and JSON Object
...it be okay if just to pass a json object? Since I will just have to insert 1 transaction per service call.
10 Answers
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Remove padding from columns in Bootstrap 3
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You'd normally use .row to wrap two columns, not .col-md-12 - that's a column encasing another column. Afterall, .row doesn't have the extra margins and padding that a col-md-12 would bring and also discounts the space that a column would introduce with negative left & right ma...
Creating default object from empty value in PHP?
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Aggregate / summarize multiple variables per group (e.g. sum, mean)
...he reshape2 package for this task:
require(reshape2)
df_melt <- melt(df1, id = c("date", "year", "month"))
dcast(df_melt, year + month ~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 2000 2 -223.76331 -288.2418017
3 2000 3 -188.83930 -481....
In Javascript, how to conditionally add a member to an object?
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In pure Javascript, I cannot think of anything more idiomatic than your first code snippet.
I...
jQuery/JavaScript to replace broken images
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31 Answers
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How do I get ruby to print a full backtrace instead of a truncated one?
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10 Answers
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