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Numbering rows within groups in a data frame
...g this approach, make sure that you are not getting conflicts between plyr and dplyr as explained in this post It can be avoided by explicitly calling dplyr::mutate(...)
– EcologyTom
Apr 10 '18 at 14:16
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Comparing strings with == which are declared final in Java
...n Java. The following segment of simple code just concatenates two strings and then compares them with == .
6 Answers
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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!!!
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Why are floating point numbers inaccurate?
...t numbers are represented a lot like scientific notation: with an exponent and a mantissa (also called the significand). A very simple number, say 9.2, is actually this fraction:
5179139571476070 * 2 -49
Where the exponent is -49 and the mantissa is 5179139571476070. The reason it is impossibl...
What is the JSF resource library for and how should it be used?
The JSF <h:outputStylesheet> , <h:outputScript> and <h:graphicImage> components have a library attribute. What is this and how should this be used? There are a lot of examples on the web which use it as follows with the common content/file type css , js and img (or ima...
OS X Terminal Colors [closed]
...rminal colors.
Edit your .bash_profile (since OS X 10.8) — or (for 10.7 and earlier): .profile or .bashrc or /etc/profile (depending on availability) — in your home directory and add following code:
export CLICOLOR=1
export LSCOLORS=GxFxCxDxBxegedabagaced
CLICOLOR=1 simply enables coloring o...
What is the performance cost of having a virtual method in a C++ class?
...any of its parent classes) means that the class will have a virtual table, and every instance will have a virtual pointer.
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Deny all, allow only one IP through htaccess
I'm trying to deny all and allow only for a single IP. But, I would like to have the following htaccess working for that single IP. I'm not finding a way to have both working: the deny all and allow only one, plus the following options:
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Determine the path of the executing BASH script [duplicate]
In a Windows command script, one can determine the directory path of the currently executing script using %~dp0 . For example:
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Counting the number of True Booleans in a Python List
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That is not idiomatic and makes "abuse" of the type coercion of bool.
– Jan Segre
Sep 4 '14 at 22:19
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