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Find the max of two or more columns with pandas
...this difference roughly remains constant, and is due to internal overhead (indexing alignment, handling NaNs, etc).
The graph was generated using perfplot. Benchmarking code, for reference:
import pandas as pd
import perfplot
np.random.seed(0)
df_ = pd.DataFrame(np.random.randn(5, 1000))
perfplo...
Relational Database Design Patterns? [closed]
...a: Dimension and Fact, OLAP design.
Fully normalized OLTP design.
Multiple indexed search columns in a dimension.
"Lookup table" that contains PK, description and code value(s) used by one or more applications. Why have code? I don't know, but when they have to be used, this is a way to manage th...
How do I get the YouTube video ID from a URL?
... = window.location.search.split('v=')[1];
var ampersandPosition = video_id.indexOf('&');
if(ampersandPosition != -1) {
video_id = video_id.substring(0, ampersandPosition);
}
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How do I bind a WPF DataGrid to a variable number of columns?
...on.Move)
{
dataGrid.Columns.Move(ne.OldStartingIndex, ne.NewStartingIndex);
}
else if (ne.Action == NotifyCollectionChangedAction.Remove)
{
foreach (DataGridColumn column in ne.OldItems)
{
...
Difference between single and double quotes in Bash
... of the topic. The explanation involves a simple variable a as well as an indexed array arr.
If we set
a=apple # a simple variable
arr=(apple) # an indexed array with a single element
and then echo the expression in the second column, we would get the result / behavior shown in the third ...
What exceptions should be thrown for invalid or unexpected parameters in .NET?
...ntOutOfRangeException – I don’t use this one much, but a common use is indexing into a collection, and giving an index which is to large.
There are other options, too, that do not focus so much on the argument itself, but rather judge the call as a whole:
InvalidOperationException – The ar...
Error in : object of type 'closure' is not subsettable
...
In general this error message means that you have tried to use indexing on a function. You can reproduce this error message with, for example
mean[1]
## Error in mean[1] : object of type 'closure' is not subsettable
mean[[1]]
## Error in mean[[1]] : object of type 'closure' is not subs...
How to copy part of an array to another array in C#?
...] b = new int[3];
Array.Copy(a, 1, b, 0, 3);
a = source array
1 = start index in source array
b = destination array
0 = start index in destination array
3 = elements to copy
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How to find where gem files are installed
... Download a gem and place it in the current directory
generate_index Generates the index files for a gem server directory
help Provide help on the 'gem' command
install Install a gem into the local repository
list Dis...
How do I put an already-running process under nohup?
...ee all the jobs that this shell started." (from [quantprinciple.com/invest/index.php/docs/tipsandtricks/unix/…)
– Dr. Jan-Philip Gehrcke
Mar 17 '11 at 13:46
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