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Extract a regular expression match
... wraps all the existing regular expression operates in a consistent syntax and adds a few that are missing:
library(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1] "12"
...
ValueError: numpy.dtype has the wrong size, try recompiling
I just installed pandas and statsmodels package on my python 2.7
When I tried "import pandas as pd", this error message comes out.
Can anyone help? Thanks!!!
...
Fast way to get image dimensions (not filesize)
I'm looking for a fast way to get the height and width of an image in pixels. It should handle at least JPG, PNG and TIFF, but the more the better. I emphasize fast because my images are quite big (up to 250 MB) and it takes soooo long to get the size with ImageMagick's identify because it obv...
Moving Files into a Real Folder in Xcode
...sing the browser in Xcode to access everything, stuff was nicely organized and I was happy.
12 Answers
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Writing a dict to txt file and reading it back?
...mes not recommended. The problem is that eval() will evaluate any string, and if someone tricked you into running a really tricky string, something bad might happen. In this case, you are just running eval() on your own file, so it should be okay.
But because eval() is useful, someone made an alt...
How to check for an undefined or null variable in JavaScript?
...xistingObj.someUndefProperty. An undefined property doesn't yield an error and simply returns undefined, which, when converted to a boolean, evaluates to false. So, if you don't care about
0 and false, using if(obj.undefProp) is ok. There's a common idiom based on this fact:
value = obj.prop || de...
Hidden features of Windows batch files
What are some of the lesser know, but important and useful features of Windows batch files?
91 Answers
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pyplot scatter plot marker size
...ases it by a factor of 4). To see this consider the following two examples and the output they produce.
# doubling the width of markers
x = [0,2,4,6,8,10]
y = [0]*len(x)
s = [20*4**n for n in range(len(x))]
plt.scatter(x,y,s=s)
plt.show()
gives
Notice how the size increases very quickly. If in...
AWS Difference between a snapshot and AMI
...
There are two types of AMIs (and corresponding instances):
instance-store (sometimes called S3-based). These are less common and I don't recommend them for beginners. An instance-store AMI is a copy of the root instance-store volume plus some metadat...
Delete last commit in bitbucket
I made a mistake and I don't know how to delete my latest push in the repository. I pull the latest updates of the app but it has conflicts and I push it to repository.
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