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Append an object to a list in R in amortized constant time, O(1)?
...ctures, they supports O(1) (amortized) appends, and allow the result to be converted back to a plain list.
expandingList <- function(capacity = 10) {
buffer <- vector('list', capacity)
length <- 0
methods <- list()
methods$double.size <- function() {
buffer...
Convert String to SecureString
How to convert String to SecureString ?
13 Answers
13
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All combinations of a list of lists
...d by itertools and a reverse version (e.g. create a list, reverse() it and convert back to tuple). Best ask a new question.
– Joachim Wagner
Feb 26 at 11:06
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How to display default text “--Select Team --” in combo box on pageload in WPF?
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You can do this without any code behind by using a IValueConverter.
<Grid>
<ComboBox
x:Name="comboBox1"
ItemsSource="{Binding MyItemSource}" />
<TextBlock
Visibility="{Binding SelectedItem, ElementName=comboBox1, Converter={StaticResource...
Convert column classes in data.table
I have a problem using data.table: How do I convert column classes? Here is a simple example: With data.frame I don't have a problem converting it, with data.table I just don't know how:
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How to generate random number with the specific length in python
...is quicker than alternatives. Just add the neccessary preceding zeros when converting to a string.
import random
num = random.randrange(1, 10**3)
# using format
num_with_zeros = '{:03}'.format(num)
# using string's zfill
num_with_zeros = str(num).zfill(3)
Alternatively if you don't want to save t...
Convert varchar to uniqueidentifier in SQL Server
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DECLARE @u uniqueidentifier SELECT @u = CONVERT(uniqueidentifier, 'c029f8be-29dc-41c1-8b38-737b4cc5a4df') *** This would be enough. Just tried it.
– Fabio Milheiro
Apr 14 '11 at 0:29
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A tool to convert MATLAB code to Python [closed]
I have a bunch of MATLAB code from my MS thesis which I now want to convert to Python (using numpy/scipy and matplotlib) and distribute as open-source. I know the similarity between MATLAB and Python scientific libraries, and converting them manually will be not more than a fortnight (provided that ...
How to select rows that have current day's timestamp?
...sed to select the rows. But the whole index is scanned (and all values are converted with DATE() to evaluate the condition) with your query. I'll update my answer with a better example.
– ypercubeᵀᴹ
Feb 8 '13 at 12:43
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Convert a list to a data frame
...gth is 132 and each item is a list of length 20. Is there a quick way to convert this structure into a data frame that has 132 rows and 20 columns of data?
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