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Remove columns from dataframe where ALL values are NA
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dplyr now has a select_if verb that may be helpful here:
library(dplyr)
temp <- data.frame(x = 1:5, y = c(1,2,NA,4, 5), z = rep(NA, 5))
not_all_na <- function(x) any(!is.na(x))
not_any_na <- function(x) all(!is.na(x))
> temp
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What's the fastest way to merge/join data.frames in R?
..., in fact, they are placed on tables which were overwritten before the sql select ever runs and that, in part, accounts for why its so slow. The idea of sqldf is that the data frames in your R session constitute the data base, not the tables in sqlite. Thus each time the code refers to an unqualif...
What is this CSS selector? [class*=“span”]
I saw this selector in Twitter Bootstrap:
4 Answers
4
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TextView Marquee not working [duplicate]
...oid:freezesText="true">
Edit (on behalf of Adil Hussain):
textView.setSelected(true) needs to be set in code behind for this to work.
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How to Store Historical Data
...erform an insert statement into FOO_Hist similar to: insert into FOO_HIST select * from FOO where id = @id .
13 Answers
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How do I specify a single test in a file with nosetests?
...n both usages should work, as per nose.readthedocs.io/en/latest/usage.html#selecting-tests. Your failure could be caused by tests not being a module in your setup?
– michaeljoseph
Mar 13 '17 at 10:04
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Android Studio: how to remove/update the “Created by” comment added to all new classes?
...lates in the left hand pane.
You have two ways you can change this...
1) Select the Includes tab and edit the Created by... text directly.
2) Select the Templates tab and edit the #parse("File Header.java") line for any template that you desire.
Personally I followed option 1) and made the d...
Counting Chars in EditText Changed Listener
...t: This is the index of where the new text will be inserted. If a range is selected, then it is the beginning index of the range.
count: This is the length of selected text that is going to be replaced. If nothing is selected then count will be 0.
after: this is the length of the text to be inserted...
Style disabled button with CSS
...ts.
For browsers/devices supporting CSS2 only, you can use the [disabled] selector.
As with the image, don't put an image in the button. Use CSS background-image with background-position and background-repeat. That way, the image dragging will not occur.
Selection problem: here is a link to the s...
JQuery: 'Uncaught TypeError: Illegal invocation' at ajax request - several elements
I have two select elements, A and B: when A's selected option changes, B's options must be updated accordingly. Each element in A implies many elements in B, it's a one-to-many relationship (A contains nations, B should contain cities located in the given nation).
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