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Change one value based on another value in pandas
... for you.
import pandas
df = pandas.read_csv("test.csv")
df.loc[df.ID == 103, 'FirstName'] = "Matt"
df.loc[df.ID == 103, 'LastName'] = "Jones"
As mentioned in the comments, you can also do the assignment to both columns in one shot:
df.loc[df.ID == 103, ['FirstName', 'LastName']] = 'Matt', 'Jone...
Are lists thread-safe?
...to concurrently access, the lists's data is not protected. For example:
L[0] += 1
is not guaranteed to actually increase L[0] by one if another thread does the same thing, because += is not an atomic operation. (Very, very few operations in Python are actually atomic, because most of them can cau...
Does the ternary operator exist in R?
...
306
As if is function in R and returns the latest evaluation, if-else is equivalent to ?:.
> a ...
How to easily resize/optimize an image size with iOS?
...one disk. Some of those images are pretty big in size (widths larger than 500 pixels, for instance). Since the iPhone doesn't even have a big enough display to show the image in its original size, I'm planning on resizing the image to something a bit smaller to save on space/performance.
...
“x not in y” or “not x in y”
... 'ham' not in 'spam and eggs'
>>> dis.dis(notin)
2 0 LOAD_CONST 1 ('ham')
3 LOAD_CONST 2 ('spam and eggs')
6 COMPARE_OP 7 (not in)
9 POP_TOP
10 LOAD_CONST ...
Multiple inputs with same name through POST in php
...
220
Change the names of your inputs:
<input name="xyz[]" value="Lorem" />
<input name="xyz...
What exactly is nullptr?
...
410
How is it a keyword and an instance of a type?
This isn't surprising. Both true and false a...
Convert Data URI to File then append to FormData
...inary data held in a string
var byteString;
if (dataURI.split(',')[0].indexOf('base64') >= 0)
byteString = atob(dataURI.split(',')[1]);
else
byteString = unescape(dataURI.split(',')[1]);
// separate out the mime component
var mimeString = dataURI.split(',')[0]...
What is the difference between ManualResetEvent and AutoResetEvent in .NET?
... |
edited Jan 7 '15 at 10:39
Yves M.
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answe...