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How to split data into training/testing sets using sample function
...e indices leads to unique observations. For instance, if you had a df with 10 rows and one column, and the one column contained 1,2,3,4,5,6,7,8,9,10 and you followed this code, what prevents a train having index 4 and test having -6 -> 10 - 6 = 4 as well?
– goldisfine
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Count how many records are in a CSV Python?
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Case insensitive searching in Oracle
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Since 10gR2, Oracle allows to fine-tune the behaviour of string comparisons by setting the NLS_COMP and NLS_SORT session parameters:
SQL> SET HEADING OFF
SQL> SELECT *
2 FROM NLS_SESSION_PARAMETERS
3 WHERE PARAMETER IN...
What is the “-->” operator in C++?
...t.
– Johannes Schaub - litb
Jan 30 '10 at 17:42
38
In Java it also compiles :)
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Max parallel http connections in a browser?
...4
Opera 12: 6
Safari 3: 4
Safari 5: 6
IE 7: 2
IE 8: 6
IE 10: 8
Chrome: 6
The limit is per-server/proxy, so your wildcard scheme will work.
FYI: this is specifically related to HTTP 1.1; other protocols have separate concerns and limitations (i.e., SPDY, TLS, HTTP 2).
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How do I enable C++11 in gcc?
...owLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\...
Excel to CSV with UTF8 encoding [closed]
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answered Nov 19 '10 at 1:08
nevets1219nevets1219
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When to use “ON UPDATE CASCADE”
... use for ON UPDATE CASCADE.
However, let's say that your primary key is a 10 digit UPC bar code and because of expansion, you need to change it to a 13-digit UPC bar code. In that case, ON UPDATE CASCADE would allow you to change the primary key value and any tables that have foreign key reference...
MySQL: @variable vs. variable. What's the difference?
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edited Jul 22 at 10:06
Community♦
111 silver badge
answered Jun 17 '09 at 23:39
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Transpose a data frame
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109
You'd better not transpose the data.frame while the name column is in it - all numeric values ...