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Change default text in input type=“file”?
...e of label for input.
<div>
<label for="files" class="btn">Select Image</label>
<input id="files" style="visibility:hidden;" type="file">
</div>
Below is the code to fetch name of the uploaded file
$("#files").change(function() {
filename = this.files[...
Drop data frame columns by name
...op=FALSE to keep R from converting your data frame to a vector if you only select a single column. Don't forget that data frames are lists, so list selection (one-dimensional like I did) works perfectly well and always returns a list. Or a data frame in this case, which is why I prefer to use it.
...
Extracting specific columns from a data frame
...r package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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View more than one project/solution in Visual Studio
... With multiple projects, if I have multiple main() methods, how do I select which I want to have compiled?
– 5Daydreams
Aug 11 at 16:12
add a comment
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RGB to hex and hex to RGB
...
I am using this with one tweak - remove non-hex chars (like a leading #) before parseInt: hex = hex.replace(/[^0-9A-F]/gi, '');
– joews
Jun 10 '14 at 13:36
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Code Wrap IntelliJ?
...o right click the gutter (the vertical bar where line number is shown) and select "Use Soft wraps" - thanks to Bajal for comment.
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SQL to determine minimum sequential days of access?
...
The answer is obviously:
SELECT DISTINCT UserId
FROM UserHistory uh1
WHERE (
SELECT COUNT(*)
FROM UserHistory uh2
WHERE uh2.CreationDate
BETWEEN uh1.CreationDate AND DATEADD(d, @days, uh1.CreationDate)
) = @days O...
Mysql error 1452 - Cannot add or update a child row: a foreign key constraint fails
... have to get rid of those first.
Here's a query that can find those IDs:
SELECT DISTINCT sourcecode_id FROM
sourcecodes_tags tags LEFT JOIN sourcecodes sc ON tags.sourcecode_id=sc.id
WHERE sc.id IS NULL;
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Regex Email validation
...he new TLD's that are being issued, as you can have TLD's with more than 3 characters now.
– AaronLS
Jul 22 '13 at 19:04
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What is this: [Ljava.lang.Object;?
... name consists of the name of the element type preceded by one or more '[' characters representing the depth of the array nesting.
The encoding of element type names is as follows:
Element Type Encoding
boolean Z
byte B
char C
double D...