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How to get a value from a cell of a dataframe?
... A B C
0 -0.074172 -0.090626 0.038272
1 -0.128545 0.762088 -0.714816
2 0.201498 -0.734963 0.558397
3 1.563307 -1.186415 0.848246
4 0.205171 0.962514 0.037709
In [17]: df.iat[0,0]
Out[17]: -0.074171888537611502
In [18]: df.at[0,'A']
Out[18]: -0.074171888537611502
...
Scala Doubles, and Precision
...rformance.
– Rex Kerr
Jun 19 '12 at 20:33
28
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z-index not working with position absolute
...iner {
width: 60px;
height: 22px;
background: #333;
border-radius: 20px;
position: relative;
cursor: pointer;
}
.change .slide {
transform: translateX(33px);
}
.slide {
transition: 0.5s;
width: 20px;
height: 20px;
background: #fff;
border-radius: 20px;
margin: 2px 2px;
...
How to set the UITableView Section title programmatically (iPhone/iPad)?
...
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edited Jun 20 at 9:12
Community♦
111 silver badge
answered May 8 '12 at 20:27
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Timeout a command in bash without unnecessary delay
...687948/…
– eel ghEEz
Jan 3 '13 at 20:57
2
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extract part of a string using bash/cut/split
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answered Oct 20 '13 at 21:16
beroeberoe
9,59744 gold badges2828 silver badges6464 bronze badges
...
Quickly reading very large tables as dataframes
... into R. See mnel's answer.
Using read_table in readr (on CRAN from April 2015). This works much like fread above. The readme in the link explains the difference between the two functions (readr currently claims to be "1.5-2x slower" than data.table::fread).
read.csv.raw from iotools provides a ...
How do Trigonometric functions work?
...
answered Dec 5 '08 at 20:59
John D. CookJohn D. Cook
27.7k1010 gold badges6262 silver badges9393 bronze badges
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Getting “Warning! PATH is not properly set up” when doing rvm use 2.0.0 --default
...?
– Muhamed Huseinbašić
Feb 12 at 20:36
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Converting between datetime, Timestamp and datetime64
...s np
>>> dt = datetime.utcnow()
>>> dt
datetime.datetime(2012, 12, 4, 19, 51, 25, 362455)
>>> dt64 = np.datetime64(dt)
>>> ts = (dt64 - np.datetime64('1970-01-01T00:00:00Z')) / np.timedelta64(1, 's')
>>> ts
1354650685.3624549
>>> datetime.utcfrom...