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what is the difference between 'transform' and 'fit_transform' in sklearn
In the sklearn-python toolbox, there are two functions transform and fit_transform about sklearn.decomposition.RandomizedPCA . The description of two functions are as follows
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What is the difference between JOIN and UNION?
What is the difference between JOIN and UNION ? Can I have an example?
15 Answers
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Detect URLs in text with JavaScript
...ou need a good regex that matches urls. This is hard to do. See here, here and here:
...almost anything is a valid URL. There
are some punctuation rules for
splitting it up. Absent any
punctuation, you still have a valid
URL.
Check the RFC carefully and see if you
can construct ...
MIN/MAX vs ORDER BY and LIMIT
...d field, using MIN() requires a single full pass of the table. Using SORT and LIMIT requires a filesort. If run against a large table, there would likely be a significant difference in percieved performance. As a meaningless data point, MIN() took .36s while SORT and LIMIT took .84s against a 106...
Building executable jar with maven?
...6: someone fixed it, this answer refers to the version preceding the edit) and this explains, at least partially, why you run into troubles.
It generates two jar files in logmanager/target: logmanager-0.1.0.jar, and logmanager-0.1.0-jar-with-dependencies.jar.
The first one is the JAR of the logma...
Pointer arithmetic for void pointer in C
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Final conclusion: arithmetic on a void* is illegal in both C and C++.
GCC allows it as an extension, see Arithmetic on void- and Function-Pointers (note that this section is part of the "C Extensions" chapter of the manual). Clang and ICC likely allow void* arithmetic for the purpose...
How can I deploy/push only a subdirectory of my git repo to Heroku?
I have a project that uses Serve and is version controlled using Git. Serve creates an output folder with static files that I want to deploy to Heroku.
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maximum value of int
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in C99 you can also use UINT64_MAX and INT64_MAX
– Dmitry Vyal
Oct 2 '13 at 9:08
3
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'float' vs. 'double' precision
... in C use IEEE 754 encoding.
This type of encoding uses a sign, a significand, and an exponent.
Because of this encoding, many numbers will have small changes to allow them to be stored.
Also, the number of significant digits can change slightly since it is a binary representation, not a decimal ...
Combine Date and Time columns using python pandas
I have a pandas dataframe with the following columns;
11 Answers
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