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Convert data.frame column to a vector?
I have a dataframe such as:
11 Answers
11
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Spring MVC: Complex object as GET @RequestParam
...eturns the following error for request mentioned in answer:
"Failed to convert value of type 'java.lang.String[]' to required type
'java.lang.Long[]'; nested exception is
java.lang.NumberFormatException: For input string: \"353,234\""
The data class will work only for the following request...
Why do you have to link the math library in C?
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On ancient systems, if math functions were contained in libc, then compiling all programs would be slower, the output executables would be larger, and runtime would require more memory, with no benefit to most programs which do not use ...
HTML character decoding in Objective-C / Cocoa Touch
...hould be substituted.” More like character. This is text, not data; upon converting the text to data, the character may occupy multiple bytes, depending on the character and the encoding.
– Peter Hosey
Jul 9 '09 at 18:17
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Remove insignificant trailing zeros from a number?
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If you convert it to a string it will not display any trailing zeros, which aren't stored in the variable in the first place since it was created as a Number, not a String.
var n = 1.245000
var noZeroes = n.toString() // "1.245"
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Convert Django Model object to dict with all of the fields intact
How does one convert a Django Model object to a dict with all of its fields? All ideally includes foreign keys and fields with editable=False .
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PostgreSQL return result set as JSON array?
...ion describes how to generate a JSON array of objects, with each row being converted to a single object. The result looks like this:
[{"a":1,"b":"value1"},{"a":2,"b":"value2"},{"a":3,"b":"value3"}]
9.3 and up
The json_agg function produces this result out of the box. It automatically figures out...
Python list subtraction operation
... @BarnabasSzabolcs: That won't save a thing, because it will convert y to a set before every check (which is similar cost to original work). You'd need to either do yset = set(y) outside the listcomp, then test if item not in yset, or as an egregious hack, do [item for yset in [set(y)]...
Convert UTC to local time in Rails 3
I'm having trouble converting a UTC Time or TimeWithZone to local time in Rails 3.
6 Answers
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Create a matrix of scatterplots (pairs() equivalent) in ggplot2
...ykey = '.ykey', yvalue = '.yvalue',
na.rm = FALSE, convert = FALSE, factor_key = FALSE) {
vars <- quos(...)
xkey <- enquo(xkey)
xvalue <- enquo(xvalue)
ykey <- enquo(ykey)
yvalue <- enquo(yvalue)
data %>% {
cbind(gather(., key = !!xkey, valu...