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Convert data.frame column format from character to factor
...fully stick back into into the dataframe, df
Another strategy would be to convert only those columns where the number of unique items is less than some criterion, let's say fewer than the log of the number of rows as an example:
cols.to.factor <- sapply( df, function(col) length(unique(col)) &l...
Convert number strings with commas in pandas DataFrame to float
...ontains numbers as strings with commas for the thousands marker. I need to convert them to floats.
3 Answers
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Converting timestamp to time ago in PHP e.g 1 day ago, 2 days ago…
I am trying to convert a timestamp of the format 2009-09-12 20:57:19 and turn it into something like 3 minutes ago with PHP.
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How to run a program without an operating system?
...s:
Make sure to use the right pins, or else you can burn your UART to USB converter, I've done it twice already by short circuiting ground and 5V...
Finally connect to the serial from the host with:
screen /dev/ttyUSB0 115200
For the Raspberry Pi, we use a Micro SD card instead of an USB stick to ...
How to convert the ^M linebreak to 'normal' linebreak in a file opened in vim?
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:e ++ff=dos followed by :set ff=unix will convert the endings to a sane format.
– Mateen Ulhaq
Mar 2 '18 at 2:22
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How to select date from datetime column?
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Interesting, if MySql implementation automatically converts DATE(datetime) to BETWEEN AND behine the scenes we get short statement and cool performance. Why not? Why they did not do this? :)
– Cherry
Dec 30 '16 at 5:04
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How to safely open/close files in python 2.4
...When you’re done with a file, call f.close() to close it and free up any system resources taken up by the open file. After calling f.close(), attempts to use the file object will automatically fail.
Hence use close() elegantly with try/finally:
f = open('file.txt', 'r')
try:
# do stuff wit...
Convert Array to Object
What is the best way to convert:
45 Answers
45
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How to cast/convert pointer to reference in C++
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Does this create a copy of ob, or just convert (if not cast) the pointer to a reference? What if ob was nullptr?
– Drew Noakes
Jun 15 '14 at 23:15
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Convert an ISO date to the date format yyyy-mm-dd in JavaScript
... note is that, since it's the ISO 8601 time format, the browser generally converts from UTC time to local timezone. Though this is simple use case where you can probably do '2013-03-10T02:00:00Z'.substring(0, 10);.
For more complex conversions date-fns is the way to go.
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