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Determine the data types of a data frame's columns
...use ?str(). To explore some examples, let's make some data:
set.seed(3221) # this makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
...
Filter rows which contain a certain string
...))
mpg cyl disp hp drat wt qsec vs am gear carb type
1 21.0 6 160.0 110 3.90 2.620 16.46 0 1 4 4 Mazda RX4
2 21.0 6 160.0 110 3.90 2.875 17.02 0 1 4 4 Mazda RX4 Wag
3 33.9 4 71.1 65 4.22 1.835 19.90 1 1 4 1 Toyota Corolla
4 21.5 4 120.1 97...
in_array multiple values
... Mark ElliotMark Elliot
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13
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How to check status of PostgreSQL server Mac OS X
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answered Sep 2 '13 at 21:55
l3xl3x
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Print a string as hex bytes?
...nd I want to print it using Python as 48:65:6c:6c:6f:20:77:6f:72:6c:64:20:21:21 .
13 Answers
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Difference between git pull and git pull --rebase
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answered Sep 21 '13 at 8:28
mvpmvp
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Compare DATETIME and DATE ignoring time portion
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answered Mar 3 '17 at 21:22
pimbrouwerspimbrouwers
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What is the difference between NaN and None?
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suchoss
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answered Jul 8 '13 at 19:16
heltonbikerheltonbiker...
Converting a column within pandas dataframe from int to string
...esult back:
df['A'] = df['A'].apply(str)
Convert the whole frame
In [21]: df.applymap(str)
Out[21]:
A B
0 0 1
1 2 3
2 4 5
3 6 7
4 8 9
In [22]: df.applymap(str).iloc[0,0]
Out[22]: '0'
df = df.applymap(str)
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How to reuse an ostringstream?
... |
edited Mar 8 '09 at 21:41
answered Mar 8 '09 at 21:08
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