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Delete the first three rows of a dataframe in pandas
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281
Use iloc:
df = df.iloc[3:]
will give you a new df without the first three rows.
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Convert data.frame columns from factors to characters
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18 Answers
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NumPy array initialization (fill with identical values)
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NumPy 1.8 introduced np.full(), which is a more direct method than empty() followed by fill() for creating an array filled with a certain value:
>>> np.full((3, 5), 7)
array([[ 7., 7., 7., 7., 7.],
[ 7., 7., ...
Why do we need argc while there is always a null at the end of argv?
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106
Yes, argv[argc]==NULL is guaranteed. See C11 5.1.2.2.1 Program startup (my emphasis)
If t...
How to use OpenSSL to encrypt/decrypt files?
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10 Answers
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All falsey values in JavaScript
...ypeof as undefined. It was a Microsoft-proprietory function in IE before IE11, and was added to the HTML spec as a "willful violation of the JavaScript specification" so that sites written for IE wouldn't break on trying to access, for example, document.all.something; it's falsy because if (document...
Unable to find the wrapper “https” - did you forget to enable it when you configured PHP?
...id I'll list out exactly everything I've done so far. I am running PHP 5.2.14 with Zend Debugging on the latest Eclipse version on my Windows XP computer. I have a 1 GB of RAM. I have XAMPP running with Apache, MySQL, and FileZilla installed.
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How to detect if CMD is running as Administrator/has elevated privileges?
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13 Answers
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Is there anyway to exclude artifacts inherited from a parent POM?
.../groupId>
<artifactId>log4j</artifactId>
<version>1.2.15</version>
<scope>provided</scope>
<exclusions>
<exclusion>
<groupId>javax.mail</groupId>
<artifactId>mail</artifactId>
</exclusion>
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