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How to use Python's pip to download and keep the zipped files for a package?
...IRC, I had to use sudo pip install <path-to-downloaded-package> --no-index --find-links `pwd`
– knocte
Nov 30 '16 at 9:09
...
Import multiple csv files into pandas and concatenate into one DataFrame
....csv")
li = []
for filename in all_files:
df = pd.read_csv(filename, index_col=None, header=0)
li.append(df)
frame = pd.concat(li, axis=0, ignore_index=True)
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JS: iterating over result of getElementsByClassName using Array.forEach
...document.getElementsByClassName("myclass")).forEach(
function(element, index, array) {
// do stuff
}
);
In older browsers which don't support Array.from, you need to use something like Babel.
ES6 also adds this syntax:
[...document.getElementsByClassName("myclass")].forEach(
...
Restricting input to textbox: allowing only numbers and decimal point
.../Check if the text already contains the . character
if (txt.value.indexOf('.') === -1) {
return true;
} else {
return false;
}
} else {
if (charCode > 31 &&
(charCode < 48 || charCode > 57))
retur...
What's the fastest way to do a bulk insert into Postgres?
...ide has some other good tips on how to speed up the process, like removing indexes and foreign keys before loading the data (and adding them back afterwards).
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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
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If you want to let PostgreSQL generate the index name, use ALTER TABLE tablename ADD UNIQUE (columns);. (Note that the CONSTRAINT keyword must be omitted.)
– jpmc26
Nov 26 '14 at 1:41
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Nullable type as a generic parameter possible?
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public static T GetValueOrDefault<T>(this IDataRecord rdr, int index)
{
object val = rdr[index];
if (!(val is DBNull))
return (T)val;
return default(T);
}
Just use it like this:
decimal? Quantity = rdr.GetValueOrDefault<decimal?>(1);
string Unit = rdr.GetVa...
Staging Deleted files
... name (e.g. dir to add dir/file1 and dir/file2) can be given to update the index to match the current state of the directory as a whole (e.g. specifying dir will record not just a file dir/file1 modified in the working tree, a file dir/file2 added to the working tree, but also a file dir/file3 remov...
How to avoid isset() and empty()
...t write a function for that. Something like:
function get_string($array, $index, $default = null) {
if (isset($array[$index]) && strlen($value = trim($array[$index])) > 0) {
return get_magic_quotes_gpc() ? stripslashes($value) : $value;
} else {
return $default;
...
How to drop a database with Mongoose?
...lutions is they rely on restarting your application if you want to get the indexes working again.
For my needs (i.e. being able to run a unit test the nukes all collections, then recreates them along with their indexes), I ended up implementing this solution:
This relies on the underscore.js and a...