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How to select the rows with maximum values in each group with dplyr? [duplicate]
...g of A and B values.
group_by( A, B) %>%
# Sort rows in descending order by "value" column.
arrange( desc(value) ) %>%
# Pick the top 1 value
slice(1) %>%
# Remember to ungroup in case you want to do further work without grouping.
ungroup()
# Answering an extension of the ...
How can I get a list of all functions stored in the database of a particular schema in PostgreSQL?
...og.pg_namespace n ON n.oid = p.pronamespace WHERE n.nspname ~ '^(public)$' ORDER BY 1, 2, 4; Above is the query generated (from \set ECHO_HIDDEN 'on').
– Simon D
Jan 6 '18 at 9:03
...
How to elegantly check if a number is within a range?
...
As others said, use a simple if.
You should think about the ordering.
e.g
1 <= x && x <= 100
is easier to read than
x >= 1 && x <= 100
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impro...
jQuery object equality
...
your equals function seems to be order-sensitive. something like stackoverflow.com/a/29648479 would work in more cases, although it's slower.
– Jayen
Dec 26 '15 at 1:57
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How do I sort a list by different parameters at different timed
...esult, which is the idea of decending (the opposite of the usual ascending order), while leaving it as zero if they were equal.
– Yishai
Dec 4 '13 at 14:05
5
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Is there a way to do method overloading in TypeScript?
... keeps your API honest as you'll avoid creating overloads with unintuitive ordering.
The general law of TypeScript overloads is:
If you can delete the overload signatures and all of your tests pass, you don’t need TypeScript overloads
You can usually achieve the same thing with optional, or...
How to get the first element of an array?
...ethod for...in should not be used to iterate over an Array where the index order is important because it doesn't guarantee the order although you can argue browsers mostly respect the order.By the way, forEach doesn't solve the issue as many suggest because you cant break it and it will run through ...
Elegant ways to support equivalence (“equality”) in Python classes
...ses, it always calls the method of the subclass operand, regardless of the order of the operands.
So here, if Number is a classic-style class:
n1 == n3 calls n1.__eq__;
n3 == n1 calls n3.__eq__;
n1 != n3 calls n1.__ne__;
n3 != n1 calls n3.__ne__.
And if Number is a new-style class:
both n1 =...
Split a vector into chunks in R
... f)
if(force.number.of.groups) {
g.names <- names(g)
g.names.ordered <- as.character(sort(as.numeric(g.names)))
} else {
g.names <- names(g[-length(g)])
g.names.ordered <- as.character(sort(as.numeric(g.names)))
g.names.ordered <- c(g.names.ordered, "overflow"...
Error Code: 1005. Can't create table '…' (errno: 150)
...ey name to test for this.
One or both of your tables is a MyISAM table. In order to use foreign keys, the tables must both be InnoDB. (Actually, if both tables are MyISAM then you won’t get an error message - it just won’t create the key.) In Query Browser, you can specify the table type.
You ha...