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filter for complete cases in data.frame using dplyr (case-wise deletion)
...his maybe as part of filter.
library('rbenchmark')
library('dplyr')
n = 5e6
n.na = 100000
df = data.frame(
x1 = sample(1:10, n, replace=TRUE),
x2 = sample(1:10, n, replace=TRUE)
)
df$x1[sample(1:n, n.na)] = NA
df$x2[sample(1:n, n.na)] = NA
benchmark(
df %>% filter(complete.cases(x...
Why is division in Ruby returning an integer instead of decimal value?
...
Andrew Marshall
87.3k1818 gold badges202202 silver badges204204 bronze badges
answered Mar 31 '11 at 16:02
veesvees
...
Git: How to return from 'detached HEAD' state
... if you do this? Isn't this a better way? stackoverflow.com/a/61489179/13087176
– user13087176
Apr 28 at 20:13
@tipsy...
Two-way encryption: I need to store passwords that can be retrieved
... bytes for the salt and 64 bytes for the hmac and the total stored size is 96 bytes. So there's at best a 80 character overhead, and at worst a 87 character overhead...
I hope that helps...
Note: 12/11/12: I just updated this class with a MUCH better encryption method, using better derived keys, ...
Specifying and saving a figure with exact size in pixels
...n example. Here's how to show an 800x800 pixel image in my monitor (my_dpi=96):
plt.figure(figsize=(800/my_dpi, 800/my_dpi), dpi=my_dpi)
So you basically just divide the dimensions in inches by your DPI.
If you want to save a figure of a specific size, then it is a different matter. Screen DPIs...
Regular expression to match a line that doesn't contain a word
...┬──┐
S = │e1│ A │e2│ B │e3│ h │e4│ e │e5│ d │e6│ e │e7│ C │e8│ D │e9│
└──┴───┴──┴───┴──┴───┴──┴───┴──┴───┴──┴───┴──┴───┴──┴───┴──┘
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Converting String to “Character” array in Java
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Gilles 'SO- stop being evil'
87.9k2424 gold badges184184 silver badges224224 bronze badges
answered Apr 4 '12 at 7:18
JDGuideJDGui...
RuntimeException: Unable to instantiate application
...swered May 5 '14 at 15:45
stefan96stefan96
8111 silver badge22 bronze badges
...
How to express a NOT IN query with ActiveRecord/Rails?
...
Andrew Marshall
87.3k1818 gold badges202202 silver badges204204 bronze badges
answered Nov 29 '10 at 19:51
jonniijonn...
How to check if remote branch exists on a given remote repository?
...a4c1b1a4be39e2f1a2bc refs/heads/2-1-stable
c6cb5a5ab00ac9e857e5b2757d2bce6a5ad14b32 refs/heads/2-2-stable
e0774e47302a907319ed974ccf59b8b54d32bbde refs/heads/2-3-stable
13ad87971cc16ebc5c286b484821e2cb0fc3e3b1 refs/heads/3-0-stable
3df6c73f9edb3a99f0d51d827ef13a439f31743a refs/heads/3...