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Creating an R dataframe row-by-row
...de in R.
If you can, allocate your entire data.frame up front:
N <- 1e4 # total number of rows to preallocate--possibly an overestimate
DF <- data.frame(num=rep(NA, N), txt=rep("", N), # as many cols as you need
stringsAsFactors=FALSE) # you don't know levels yet...
if A vs if A is not None:
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answered Oct 19 '11 at 4:09
Greg HewgillGreg Hewgill
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Importing a Maven project into Eclipse from Git
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Maarten Bodewes
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answered Sep 1 '11 at 11:56
Sri SankaranSr...
Python Image Library fails with message “decoder JPEG not available” - PIL
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libjpeg-dev is required to be able to process jpegs with pillow (or PIL), so you need to insta...
Access nested dictionary items via a list of keys?
...Dict, ["b", "v", "y"])
2
>>> setInDict(dataDict, ["b", "v", "w"], 4)
>>> import pprint
>>> pprint.pprint(dataDict)
{'a': {'r': 1, 's': 2, 't': 3},
'b': {'u': 1, 'v': {'w': 4, 'x': 1, 'y': 2, 'z': 3}, 'w': 3}}
Note that the Python PEP8 style guide prescribes snake_case na...
How to detect Ctrl+V, Ctrl+C using JavaScript?
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jackocnrjackocnr
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Change key pair for ec2 instance
...6yegor256
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How do I specify different layouts for portrait and landscape orientations?
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Create a layout-land directory and put the landscape version of your layout XML file in that dir...
Processing Symbol Files in Xcode
...a specific CPU type. The currently CPU types needed are armv7 (e.g. iPhone 4, iPhone 4s), armv7s (e.g. iPhone 5) and arm64 (e.g. iPhone 5s).
So if you want to symbolicate a crash report that happened on an iPhone 5 with armv7s and only have the symbols for armv7 for that specific iOS version, Xcode...
How do I find numeric columns in Pandas?
...exclude. So isNumeric would look like:
numerics = ['int16', 'int32', 'int64', 'float16', 'float32', 'float64']
newdf = df.select_dtypes(include=numerics)
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