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Why should we NOT use sys.setdefaultencoding(“utf-8”) in a py script?
...
143
As per the documentation: This allows you to switch from the default ASCII to other encodings su...
How to implement “select all” check box in HTML?
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316
<script language="JavaScript">
function toggle(source) {
checkboxes = document.getElem...
Creating range in JavaScript - strange syntax
...0); //true
arr[0]; //'a'
Object.keys(arr); //['0', '1', '2']
arr.length; //3, implies arr[3] === undefined
//we expand the array by 1 item
arr.length = 4;
arr[3]; //undefined
arr.hasOwnProperty(3); //false
Object.keys(arr); //['0', '1', '2']
We get to the inherent difference between the number of...
Accessing bash command line args $@ vs $*
...oted. Let me illustrate the differences:
$ set -- "arg 1" "arg 2" "arg 3"
$ for word in $*; do echo "$word"; done
arg
1
arg
2
arg
3
$ for word in $@; do echo "$word"; done
arg
1
arg
2
arg
3
$ for word in "$*"; do echo "$word"; done
arg 1 arg 2 arg 3
$ for word in "$@"; do echo "$word"; do...
Fastest way to replace NAs in a large data.table
...
system.time(a_gdata = f_gdata(dt1))
user system elapsed
18.805 12.301 134.985
system.time(a_andrie = f_andrie(dt1))
Error: cannot allocate vector of size 305.2 Mb
Timing stopped at: 14.541 7.764 68.285
system.time(f_dowle(dt1))
user system elapsed
7.452 4.144 19.590 # EDIT h...
Calculate last day of month in JavaScript
...1, 0);
alert(d); // last day in January
IE 6: Thu Jan 31 00:00:00 CST 2008
IE 7: Thu Jan 31 00:00:00 CST 2008
IE 8: Beta 2: Thu Jan 31 00:00:00 CST 2008
Opera 8.54: Thu, 31 Jan 2008 00:00:00 GMT-0600
Opera 9.27: Thu, 31...
Why are floating point numbers inaccurate?
...icand). A very simple number, say 9.2, is actually this fraction:
5179139571476070 * 2 -49
Where the exponent is -49 and the mantissa is 5179139571476070. The reason it is impossible to represent some decimal numbers this way is that both the exponent and the mantissa must be integers. In othe...
How to get number of entries in a Lua table?
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132
You already have the solution in the question -- the only way is to iterate the whole table wit...
Rails: Is there a rails trick to adding commas to large numbers?
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354
You want the number_with_delimiter method. For example:
<%= number_with_delimiter(@number,...
get list of pandas dataframe columns based on data type
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320
If you want a list of columns of a certain type, you can use groupby:
>>> df = pd.Da...