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Specifying rails version to use when creating a new application
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edited Sep 20 '11 at 16:23
Paweł Gościcki
7,05755 gold badges5555 silver badges7474 bronze badges
ans...
Remove rows with all or some NAs (missing values) in data.frame
...ul mmus rnor cfam
2 ENSG00000199674 0 2 2 2 2
6 ENSG00000221312 0 1 2 3 2
na.omit is nicer for just removing all NA's. complete.cases allows partial selection by including only certain columns of the dataframe:
> final[complete.cases(final[ , 5:6]),]
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Replacement for “rename” in dplyr
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dplyr version 0.3 added a new rename() function that works just like plyr::rename().
df <- rename(df, new_name = old_name)
share
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imp...
Installing Ruby Gem in Windows
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73
I recommend you just use rubyinstaller
It is recommended by the official Ruby page - see https:...
What's the difference between RANK() and DENSE_RANK() functions in oracle?
... assigned the same rank, with the next ranking(s) skipped. So, if you have 3 items at rank 2, the next rank listed would be ranked 5.
DENSE_RANK again gives you the ranking within your ordered partition, but the ranks are consecutive. No ranks are skipped if there are ranks with multiple items.
As...
Is there a difference between using a dict literal and a dict constructor?
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answered Jul 7 '11 at 12:43
John La RooyJohn La Rooy
249k4646 gold badges326326 silver badges469469 bronze badges
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Base64 length calculation?
...log2(64) = 6).
Therefore 4 chars are used to represent 4 * 6 = 24 bits = 3 bytes.
So you need 4*(n/3) chars to represent n bytes, and this needs to be rounded up to a multiple of 4.
The number of unused padding chars resulting from the rounding up to a multiple of 4 will obviously be 0, 1, 2 or...
What is the difference between Python's list methods append and extend?
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5329
append: Appends object at the end.
x = [1, 2, 3]
x.append([4, 5])
print (x)
gives you: [1, ...
Numpy array dimensions
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513
It is .shape:
ndarray.shape
Tuple of array dimensions.
Thus:
>>> a.shape
(2, 2...
Matplotlib scatter plot with different text at each data point
... could use annotate() while iterating over the values in n.
y = [2.56422, 3.77284, 3.52623, 3.51468, 3.02199]
z = [0.15, 0.3, 0.45, 0.6, 0.75]
n = [58, 651, 393, 203, 123]
fig, ax = plt.subplots()
ax.scatter(z, y)
for i, txt in enumerate(n):
ax.annotate(txt, (z[i], y[i]))
There are a lot of...