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Import multiple csv files into pandas and concatenate into one DataFrame
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If you have same columns in all your csv files then you can try the code below.
I have added header=0 so that after reading csv first row can be assigned as the column names.
import pandas as pd
import glob
path = r'C:\DRO\DCL_rawdata_files' # use you...
Can an Option in a Select tag carry multiple values?
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I was actually wondering this today, and I achieved it by using the php explode function, like this:
HTML Form (in a file I named 'doublevalue.php':
<form name="car_form" method="post" action="doublevalue_action.php">
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How can I add or update a query string parameter?
... @JarónBarends - Tweak value check to check against undefined and null to allow setting 0 values
Third Update
There was a bug where removing a querystring variable directly before a hashtag would lose the hashtag symbol which has been fixed
Fourth Update
Thanks @rooby for pointing out a regex o...
How to find time complexity of an algorithm
...term is 2 million and the second term is only 2.
For this reason, we drop all but the largest terms for large N.
So, now we have gone from 2N + 2 to 2N.
Traditionally, we are only interested in performance up to constant factors.
This means that we don't really care if there is some constant mu...
Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
... a matrix of size 2^n is slower than transposing one of size 2^n+1 . For small values of n , the difference is not major.
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promise already under evaluation: recursive default argument reference or earlier problems?
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Formal arguments of the form x=x cause this. Eliminating the two instances where they occur we get:
f <- function(x, T) {
10 * sin(0.3 * x) * sin(1.3 * x^2) + 0.001 * x^3 + 0.2 * x + 80
}
g <- function(x, T, f. = f) { ## 1. note f.
exp(-...
Create folder with batch but only if it doesn't already exist
... @jpmc26 You are right, a trailing slash does the job and is actually preferable since it works with quotes (thus allowing you to have spaces in the directory path). To distinguish between either file/directory, this will work: if exist "a" if not exist "a\" (echo "it's a file") else (echo...
How do I create a readable diff of two spreadsheets using git diff?
...e a lot of spreadsheets (xls) in our source code repository. These are usually edited with gnumeric or openoffice.org, and are mostly used to populate databases for unit testing with dbUnit . There are no easy ways of doing diffs on xls files that I know of, and this makes merging extremely tedio...
How can I view array structure in JavaScript with alert()?
...t language spec, so you shouldn't rely on the JSON object being present in all browsers, but for debugging purposes it's incredibly useful.
I tend to use the jQuery-json plugin as follows:
alert( $.toJSON(myArray) );
This prints the array in a format like
[5, 6, 7, 11]
However, for debugging ...
Globally catch exceptions in a WPF application?
...ication where parts of it may throw exceptions at runtime. I'd like to globally catch any unhandled exception and log them, but otherwise continue program execution as if nothing happened (kinda like VB's On Error Resume Next ).
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