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R programming: How do I get Euler's number?
...
150
The R expression
exp(1)
represents e, and
exp(2)
represents e^2.
This works because exp i...
setting y-axis limit in matplotlib
...t axes".
– Lenar Hoyt
May 8 '17 at 10:57
39
you can also set one value None which leaves the calc...
List of installed gems?
... Gem::Requirement.default)
specs = Gem.source_index.search(dep)
puts specs[0..5].map{ |s| "#{s.name} #{s.version}" }
# >> Platform 0.4.0
# >> abstract 1.0.0
# >> actionmailer 3.0.5
# >> actionpack 3.0.5
# >> activemodel 3.0.5
# >> activerecord 3.0.5
Here's an ...
NumPy or Pandas: Keeping array type as integer while having a NaN value
...
This capability has been added to pandas (beginning with version 0.24):
https://pandas.pydata.org/pandas-docs/version/0.24/whatsnew/v0.24.0.html#optional-integer-na-support
At this point, it requires the use of extension dtype Int64 (capitalized), rather than the default dtype int64 (lowe...
get list from pandas dataframe column
..._one_arr}\ntype:{type(col_one_arr)}")
Output:
DataFrame:
one two
a 1.0 1
b 2.0 2
c 3.0 3
d NaN 4
column types:
one float64
two int64
dtype: object
col_one_list:
[1.0, 2.0, 3.0, nan]
type:<class 'list'>
col_one_arr:
[ 1. 2. 3. nan]
type:<class 'numpy.ndarray...
How to count certain elements in array?
...
Very simple:
var count = 0;
for(var i = 0; i < array.length; ++i){
if(array[i] == 2)
count++;
}
share
|
improve this answer
...
How to get box-shadow on left & right sides only
...
+50
NOTE: I suggest checking out @Hamish's answer below; it doesn't involve the imperfect "masking" in the solution described here.
...
Chmod recursively
...
edited Nov 14 '12 at 11:30
answered Nov 14 '12 at 11:23
Fr...
How do I use the includes method in lodash to check if an object is in the collection?
... fodma1
2,71111 gold badge1919 silver badges4040 bronze badges
answered Aug 6 '14 at 22:16
p.s.w.gp.s.w.g
132k2222 gold bad...
ReactJS: Modeling Bi-Directional Infinite Scrolling
...render them, it's really cheap to just allocate them and discard them. If 10k allocations is too big, you can instead pass a function that takes a range and return the elements.
<List>
{thousandelements.map(function() { return <Element /> })}
</List>
Your List component is kee...