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python dataframe pandas drop column using int
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edited Feb 16 '16 at 10:48
frederikf
333 bronze badges
answered Nov 30 '13 at 15:06
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Write to .txt file?
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270
FILE *f = fopen("file.txt", "w");
if (f == NULL)
{
printf("Error opening file!\n");
exit...
string.Format() giving “Input string is not in correct format”
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305
string.Format() considers each '{' or '}' to be part of a placeholder (like '{0}' you already u...
Assigning a variable NaN in python without numpy
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170
Yes -- use math.nan.
>>> from math import nan
>>> print(nan)
nan
>>>...
Line-breaking widget layout for Android
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Since May 2016 there is new layout called FlexboxLayout from Google, which is highly configurable for purpose you want.
FlexboxLayout is in Google GitHub repository at https://github.com/google/flexbox-layout at this moment.
You can u...
Replace only text inside a div using jquery
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edited Oct 29 '14 at 20:50
cuSK
7701010 silver badges2323 bronze badges
answered Aug 8 '12 at 14:56
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How to select only the first rows for each unique value of a column
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answered Jan 11 '11 at 20:50
gbngbn
382k7272 gold badges532532 silver badges629629 bronze badges
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Difference between `mod` and `rem` in Haskell
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20
I had the same question about rem and mod in Clojure, and this was the answer.
– noahlz
Jul 11 '12 at...
Check image width and height before upload with Javascript
...file").change(function (e) {
var file, img;
if ((file = this.files[0])) {
img = new Image();
var objectUrl = _URL.createObjectURL(file);
img.onload = function () {
alert(this.width + " " + this.height);
_URL.revokeObjectURL(objectUrl);
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Pandas aggregate count distinct
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How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "user_id...