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Warning message: In `…` : invalid factor level, NA generated
... "Type" to be a character.
> fixed <- data.frame("Type" = character(3), "Amount" = numeric(3))
> str(fixed)
'data.frame': 3 obs. of 2 variables:
$ Type : Factor w/ 1 level "": NA 1 1
$ Amount: chr "100" "0" "0"
>
> fixed <- data.frame("Type" = character(3), "Amount" = nume...
How to filter SQL results in a has-many-through relation
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13 Answers
13
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How to find all the subclasses of a class given its name?
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337
New-style classes (i.e. subclassed from object, which is the default in Python 3) have a __sub...
Error handling with node.js streams
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edited Sep 19 '19 at 23:46
Ori Price
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answered...
Read whole ASCII file into C++ std::string [duplicate]
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edited Feb 23 '17 at 19:31
resueman
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Double vs. BigDecimal?
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463
A BigDecimal is an exact way of representing numbers. A Double has a certain precision. Working ...
Convert MySQL to SQlite [closed]
...ader, the script can be used like this:
./mysql2sqlite.sh myDbase | sqlite3 database.sqlite
alternatives
an updated version https://github.com/dumblob/mysql2sqlite
A simpler script was posted at the the MySQL Forums
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What is a predicate in c#? [duplicate]
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483
Predicate<T> is a functional construct providing a convenient way of basically testing if ...
count (non-blank) lines-of-code in bash
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edited Sep 22 '08 at 13:37
answered Sep 22 '08 at 13:23
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Is it possible to add dynamically named properties to JavaScript object?
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var data = {
'PropertyA': 1,
'PropertyB': 2,
'PropertyC': 3
};
data["PropertyD"] = 4;
// dialog box with 4 in it
alert(data.PropertyD);
alert(data["PropertyD"]);
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