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Cleaning `Inf` values from an R dataframe
...,lapply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal copying.
DT <- data.table(dat)
invisible(lapply(names(DT),function(.name) set(DT, which(is.infinite(DT[[.name]])), j = .name,value =NA)))
Or using colum...
Numbering rows within groups in a data frame
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Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
library(plyr)
ddply(df, .(cat), mutate, id = seq_along(val))
or:
library(dplyr)
df %>% group_by(cat) %>% mutate(id = row_number())
or (the most memor...
How to Use slideDown (or show) function on a table row?
I'm trying to add a row to a table and have that row slide into view, however the slidedown function seems to be adding a display:block style to the table row which messes up the layout.
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Apply style to only first level of td tags
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This style:
table tr td { border: 1px solid red; }
td table tr td { border: none; }
gives me:
this http://img12.imageshack.us/img12/4477/borders.png
However, using a class is probably the right approach here.
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How to avoid mysql 'Deadlock found when trying to get lock; try restarting transaction'
I have a innoDB table which records online users. It gets updated on every page refresh by a user to keep track of which pages they are on and their last access date to the site. I then have a cron that runs every 15 minutes to DELETE old records.
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Joining three tables using MySQL
I have three tables named
8 Answers
8
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Repeat table headers in print mode
Is it possible in CSS using a property inside an @page to say that table headers (th) should be repeated on every page if the table spreads over multiple pages?
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It has a DefiningQuery but no InsertFunction element… err
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Well when a table is encountered without a PrimaryKey it is treated as a View.
And views show up in the EDMX file (open in an XML editor to see) in the StorageModel\EntitySet[n]\DefiningQuery element.
When you have a DefiningQuery the ...
How to select the nth row in a SQL database table?
...ideally) database agnostic ways of selecting the n th row from a database table. It would also be interesting to see how this can be achieved using the native functionality of the following databases:
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Text-align class for inside a table
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This does not work for table cells unfortunately. It may simply be a CSS order issue. See this issue [github.com/twitter/bootstrap/issues/6837]. Should be fixed in version 3.0.
– David
Apr 5 '13 at 17:05
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