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PHP: merge two arrays while keeping keys instead of reindexing?
...
You can simply 'add' the arrays:
>> $a = array(1, 2, 3);
array (
0 => 1,
1 => 2,
2 => 3,
)
>> $b = array("a" => 1, "b" => 2, "c" => 3)
array (
'a' => 1,
'b' => 2,
'c' => 3,
)
>> $a + $b
array (
0 => 1,
1 => 2,
2 =&g...
Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
... from pandas import *
In [2]: def calculate(x):
...: return x*2, x*3
...:
In [3]: df = DataFrame({'a': [1,2,3], 'b': [2,3,4]})
In [4]: df
Out[4]:
a b
0 1 2
1 2 3
2 3 4
In [5]: df["A1"], df["A2"] = zip(*df["a"].map(calculate))
In [6]: df
Out[6]:
a b A1 A2
0 1 2 2...
How to count the frequency of the elements in an unordered list?
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33 Answers
33
Active
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Bootstrap 3 - Why is row class is wider than its container?
I just started using Bootstrap 3. I am having a difficult time
understanding how the row class works.
Is there a way to avoid the padding-left and padding-right ?
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Reloading module giving NameError: name 'reload' is not defined
I'm trying to reload a module I have already imported in Python 3. I know that you only need to import once and executing the import command again won't do anything.
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What's the difference between tilde(~) and caret(^) in package.json?
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4053
See the NPM docs and semver docs:
~version “Approximately equivalent to version”, will upda...
What is sys.maxint in Python 3?
...a maximum integer, and I've read to use "sys.maxint" . However, in Python 3 when I call it I get:
6 Answers
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Pass a data.frame column name to a function
... just use the column name directly:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[,column])
}
fun1(df, "B")
fun1(df, c("B","A"))
There's no need to use substitute, eval, etc.
You can even pass the desired function as a parameter:
fun1 <- function(x, colu...
Remove all occurrences of a value from a list?
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23 Answers
23
Active
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while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
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3 Answers
3
Active
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