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How To Change DataType of a DataColumn in a DataTable?
... Love the solution - Elegant! However ImportRow() does not seem to convert string values to float values for me. Am I missing something here?
– yangli.liy
Sep 17 '14 at 15:54
...
Convert data.frame columns from factors to characters
... data.frame(lapply(bob, as.character), stringsAsFactors=FALSE)
This will convert all variables to class "character", if you want to only convert factors, see Marek's solution below.
As @hadley points out, the following is more concise.
bob[] <- lapply(bob, as.character)
In both cases, lapp...
Convert data.frame column format from character to factor
...fully stick back into into the dataframe, df
Another strategy would be to convert only those columns where the number of unique items is less than some criterion, let's say fewer than the log of the number of rows as an example:
cols.to.factor <- sapply( df, function(col) length(unique(col)) &l...
How to format an inline code in Confluence?
...stackoverflow inline code
Categories: Formatting
Macro Body Processing: Convert wiki markup to HTML
Output Format: HTML
Template:
## Macro title: Inline Code
## Macro has a body: Y
## Body processing: Convert wiki markup to HTML
## Output: HTML
##
## Developed by: My Name
## Date created: dd/mm/...
How can I reliably get an object's address when operator& is overloaded?
...ent and returning no result. This reference to a function can be trivially converted into a pointer to function -- from @Konstantin: According to 13.3.3.2 both T & and T * are indistinguishable for functions. The 1st one is an Identity conversion and the 2nd one is Function-to-Pointer conversion...
Search text in fields in every table of a MySQL database
...NOT
# MISUSE AND YOU COULD CRASH A LARGE SERVER
SELECT
CONCAT('SELECT CONVERT(',A.COLUMN_NAME, ' USING utf8) FROM ', A.TABLE_SCHEMA, '.', A.TABLE_NAME,
' WHERE CONVERT(',A.COLUMN_NAME, ' USING utf8) IN (\'%someText%\');')
FROM INFORMATION_SCHEMA.COLUMNS A
WHERE
A.TABLE...
Importing a Maven project into Eclipse from Git
...ion to these issues:
You can't install m2e-egit (I get an error in Juno)
Converting a general project (connected to your Git repository) to a Maven project isn't working for you (The Import Maven Projects step seems essential)
Importing Maven Projects from your repository on the filesystem isn't s...
Reshaping data.frame from wide to long format
I have some trouble to convert my data.frame from a wide table to a long table.
At the moment it looks like this:
9 Answe...
Convert PDF to image with high resolution
I'm trying to use the command line program convert to take a PDF into an image (JPEG or PNG). Here is one of the PDFs that I'm trying to convert.
...
What's the difference between a temp table and table variable in SQL Server?
...RAN EndBatch
COMMIT')
DECLARE @LSN_HEX NVARCHAR(25) =
CAST(CAST(CONVERT(varbinary,SUBSTRING(@LSN, 1, 8),2) AS INT) AS VARCHAR) + ':' +
CAST(CAST(CONVERT(varbinary,SUBSTRING(@LSN, 10, 8),2) AS INT) AS VARCHAR) + ':' +
CAST(CAST(CONVERT(varbinary,SUBSTRING(@LSN, 19, 4),2) AS...