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How do I make a list of data frames?
...nt you're working in:
d1 <- data.frame(y1 <- c(1, 2, 3), y2 <- c(4, 5, 6))
y1
# [1] 1 2 3
y2
# [1] 4 5 6
This won't have the seemingly desired effect of creating column names in the data frame:
d1
# y1....c.1..2..3. y2....c.4..5..6.
# 1 1 4
# 2 ...
How can I check which version of Angular I'm using?
...
Kabb5
3,39822 gold badges2929 silver badges4949 bronze badges
answered Apr 15 '13 at 14:35
TheHippoTheHippo
52.5k1212 gol...
How to check status of PostgreSQL server Mac OS X
... |
edited Nov 2 '11 at 4:03
answered Nov 2 '11 at 3:25
B...
Python: print a generator expression?
...;> (x*x for x in range(10))
<generator object <genexpr> at 0xb7485464>
This is sometimes called a generator comprehension, although I think the official name still is generator expression, there isn't really any difference, the parenthesis are only there to make the syntax valid. Yo...
Compare two Byte Arrays? (Java)
... |
edited Jan 12 '14 at 10:10
answered Mar 26 '11 at 2:49
...
Counting the Number of keywords in a dictionary in python
...
429
len(yourdict.keys())
or just
len(yourdict)
If you like to count unique words in the file,...
++someVariable vs. someVariable++ in JavaScript
...swer. ;-)
– Chris
Aug 12 '10 at 16:34
2
What would this look like if you used + 1 instead of ++? ...
Transpose list of lists
...
How about
map(list, zip(*l))
--> [[1, 4, 7], [2, 5, 8], [3, 6, 9]]
For python 3.x users can use
list(map(list, zip(*l)))
Explanation:
There are two things we need to know to understand what's going on:
The signature of zip: zip(*iterables) This means zip ...
How to remove gaps between subplots in matplotlib?
...yplot as plt
import matplotlib.gridspec as gridspec
plt.figure(figsize = (4,4))
gs1 = gridspec.GridSpec(4, 4)
gs1.update(wspace=0.025, hspace=0.05) # set the spacing between axes.
for i in range(16):
# i = i + 1 # grid spec indexes from 0
ax1 = plt.subplot(gs1[i])
plt.axis('on')
ax...
Performance of foreach, array_map with lambda and array_map with static function
... 1M numbers across a dozen attempts:
Foreach: 0.7 sec
Map on closure: 3.4 sec
Map on function name: 1.2 sec.
Supposing the lackluster speed of the map on closure was caused by the closure possibly being evaluated each time, I also tested like this:
function useMapClosure($numbers) {
$closu...