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Filter dataframe rows if value in column is in a set list of values [duplicate]
... regular expressions.
For example, if we want to return a DataFrame where all of the stock IDs which begin with '600' and then are followed by any three digits:
>>> rpt[rpt['STK_ID'].str.contains(r'^600[0-9]{3}$')] # ^ means start of string
... STK_ID ... ...
Modulo operation with negative numbers
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C99 requires that when a/b is representable:
(a/b) * b + a%b shall equal a
This makes sense, logically. Right?
Let's see what this leads to:
Example A. 5/(-3) is -1
=> (-1) * (-3) + 5%(-3) = 5
This can only happen if 5%(-3) is 2.
Example B. (-5)/3 is -1
=> (-1) * 3 + (-5...
how to show lines in common (reverse diff)?
...ile2, and they have both overlapping and non-overlapping rows. If you want all and only the non-overlapping rows, using fgrep -v file1 file2 will only return the non-overlapping rows in file2, and none of the additional non-overlapping rows in file1. This may be obvious to some, but better to state ...
How do I create a new Swift project without using Storyboards?
Creating a new project in XCode 6 doesn't allow to disable Storyboards. You can only select Swift or Objective-C and to use or not Core Data.
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How many threads can a Java VM support?
...ts.
There are several parameters here. The specific VM, plus there are usually run-time parameters on the VM as well. That's somewhat driven by the operating system: what support does the underlying OS have for threads and what limitations does it put on them? If the VM actually uses OS-level thr...
How can I show dots (“…”) in a span with hidden overflow?
... standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book</span>
JSFiddle
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How to copy a directory using Ant
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@s1n This commands only copies all the contents of src_dir to ../new/dir and not the src_dir. How do we copy src_dir (directory) to another location?
– Pipalayan Nayak
Dec 3 '11 at 19:24
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Passing a string with spaces as a function argument in bash
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This works very well for me also. If we are calling another function inside myFunction then pass arguments with quotes. Cheers :)
– minhas23
May 8 '14 at 11:04
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Correct way to define Python source code encoding
...f you want to be 100% python-docs-recommendation-compatible.
More specifically, you need to use whatever is recognized by Python and the specific editing software you use (if it needs/accepts anything at all). E.g. the coding form is recognized (out of the box) by GNU Emacs but not Vim (yes, withou...
Getting an “ambiguous redirect” error
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Bash can be pretty obtuse sometimes.
The following commands all return different error messages for basically the same error:
$ echo hello >
bash: syntax error near unexpected token `newline`
$ echo hello > ${NONEXISTENT}
bash: ${NONEXISTENT}: ambiguous redirect
$ echo hello ...