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jQuery trigger file input
...r;
position: absolute;
top: 0px;
right: 0px;
font-size: 100px;
z-index: 2;
opacity: 0.0; /* Standard: FF gt 1.5, Opera, Safari */
filter: alpha(opacity=0); /* IE lt 8 */
-ms-filter: "alpha(opacity=0)"; /* IE 8 */
-khtml-opacity: 0.0; /* Safari 1.x */
-moz-opacity: 0.0; /* FF lt ...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
...df = df.drop(some labels)
df = df.drop(df[<some boolean condition>].index)
Example
To remove all rows where column 'score' is < 50:
df = df.drop(df[df.score < 50].index)
In place version (as pointed out in comments)
df.drop(df[df.score < 50].index, inplace=True)
Multiple condit...
How to generate a create table script for an existing table in phpmyadmin?
How can I generate a create table script for an existing table in phpmyadmin?
10 Answers
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PostgreSQL create table if not exists
... CONSTRAINT pk_sch_foo PRIMARY KEY (id));
CREATE INDEX /* IF NOT EXISTS add for PostgreSQL 9.5+ */ idx_sch_foo_demo_column ON sch.foo(demo_column);
CREATE INDEX /* IF NOT EXISTS add for PostgreSQL 9.5+ */ idx_sch_foo_demo_column2 ON sch.foo(demo_column2);...
How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
... when the history table is overwritten by a different branch with the same index into the branching table. In a tight loop, and assuming a branch goes one way most of the time, the branch predictor will likely begin guessing the correct branch very quickly. - your friend in pedantry.
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When and why are database joins expensive?
... working set. Joins involving properly selected keys with correctly set up indexes are cheap, not expensive, because they allow significant pruning of the result before the rows are materialised.
Materialising the result involves bulk disk reads which are the most expensive aspect of the exercise ...
Which mime type should I use for mp3
...g to decide which mime type to choose for returning mp3 data (served up by php)
5 Answers
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How do you use String.substringWithRange? (or, how do Ranges work in Swift?)
...You can use the substringWithRange method. It takes a start and end String.Index.
var str = "Hello, playground"
str.substringWithRange(Range<String.Index>(start: str.startIndex, end: str.endIndex)) //"Hello, playground"
To change the start and end index, use advancedBy(n).
var str = "Hello...
How do I create test and train samples from one dataframe with pandas?
...rac=0.8,random_state=200) #random state is a seed value
test=df.drop(train.index)
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Using numpy to build an array of all combinations of two arrays
... TypeError: slice indices must be integers or None or have an __index__ method thrown by cartesian(arrays[1:], out=out[0:m,1:])
– Boern
Sep 25 '17 at 15:48
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