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How to get users to read error messages?
...ind yourself at a high risk that users will not read your carefully worded and enlightening error messages, but just click on the first button available with a shrug of frustration.
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Force R not to use exponential notation (e.g. e+10)?
...a grey area. You need to recall that R will always invoke a print method, and these print methods listen to some options. Including 'scipen' -- a penalty for scientific display. From help(options):
‘scipen’: integer. A penalty to be applied when deciding to print
numeric value...
How to center align the cells of a UICollectionView?
I am currently using UICollectionView for the user interface grid, and it works fine. However, I'd like to be enable horizontal scrolling. The grid supports 8 items per page and when the total number of items are, say 4, this is how the items should be arranged with horizontal scroll direction ena...
How do I perform the SQL Join equivalent in MongoDB?
...t array field>
}
}
Of course Mongo is not a relational database, and the devs are being careful to recommend specific use cases for $lookup, but at least as of 3.2 doing join is now possible with MongoDB.
share
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Java compiler level does not match the version of the installed Java project facet
...you are using the m2e plugin in Eclipse, you'll need to specify the source and target versions as 1.6 for maven-compiler-plugin. m2e uses these values to determine the project's Java compiler level. A snippet of the POM is shown below:
<build>
<plugins>
<plugin>
<ar...
pandas read_csv and filter columns with usecols
I have a csv file which isn't coming in correctly with pandas.read_csv when I filter the columns with usecols and use multiple indexes.
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What does the ^ operator do in Java?
...--- xor
3 = 011
This the truth table for bitwise (JLS 15.22.1) and logical (JLS 15.22.2) xor:
^ | 0 1 ^ | F T
--+----- --+-----
0 | 0 1 F | F T
1 | 1 0 T | T F
More simply, you can also think of xor as "this or that, but not both!".
See also
Wikipedia: exclusive-...
How do I convert a column of text URLs into active hyperlinks in Excel?
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If you don't want to make a macro and as long as you don't mind an additional column, then just create a new column alongside your column of URLs.
In the new column type in the formula =HYPERLINK(A1) (replacing A1 with whatever cell you are interested in). T...
Python to print out status bar and percentage
...character (carriage return) resets the cursor to the beginning of the line and allows you to write over what was previously on the line.
from time import sleep
import sys
for i in range(21):
sys.stdout.write('\r')
# the exact output you're looking for:
sys.stdout.write("[%-20s] %d%%" %...
Make Iframe to fit 100% of container's remaining height
I want to design a web page with a banner and an iframe. I hope the iframe can fill all the remaining page height and be resized automatically as the browser is resizing. Is it possible to get it done without writing JavaScript code, only with CSS?
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