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Swift: Testing optionals for nil
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For those who are new to swift as I am and are wondering: You still have to unwrap xyz inside the if block. It's safe though, even if you force unwrap
– Omar
Jun 10 '19 at 1:05
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HTTP vs HTTPS performance
Are there any major differences in performance between http and https? I seem to recall reading that HTTPS can be a fifth as fast as HTTP. Is this valid with the current generation webservers/browsers? If so, are there any whitepapers to support it?
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RedirectToAction with parameter
...arameter appears in the URL, which is based on how the RouteConfig file is and how routing mechanisms are. For instance, new { id = 100 } can produce the URL "/100", while new {groupId = 100} might be interpreted as a query string (as was mentioned above), resulting in the URL "?groupId=100".
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Generate a random point within a circle (uniformly)
I need to generate a uniformly random point within a circle of radius R .
21 Answers
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How to pass parameters to a modal?
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To pass the parameter you need to use resolve and inject the items in controller
$scope.Edit = function (Id) {
var modalInstance = $modal.open({
templateUrl: '/app/views/admin/addeditphone.html',
controller: 'EditCtrl',
resolve: {
editId: f...
How to convert hex to rgb using Java?
...cter case each value must be * 255 / 16. I tested this with "000", "aaa", and "fff", and they all work properly now.
– Andrew
Apr 14 '16 at 16:04
add a comment
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Setting different color for each series in scatter plot on matplotlib
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I don't know what you mean by 'manually'. You can choose a colourmap and make a colour array easily enough:
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.cm as cm
x = np.arange(10)
ys = [i+x+(i*x)**2 for i in range(10)]
colors = cm.rainbow(np.linspace(0, 1, len(ys)))
f...
Python pandas: fill a dataframe row by row
The simple task of adding a row to a pandas.DataFrame object seems to be hard to accomplish. There are 3 stackoverflow questions relating to this, none of which give a working answer.
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Reducing MongoDB database file size
...tabase that was once large (>3GB). Since then, documents have been deleted and I was expecting the size of the database files to decrease accordingly.
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numpy: most efficient frequency counts for unique values in an array
...p.array([1,1,1,2,2,2,5,25,1,1])
y = np.bincount(x)
ii = np.nonzero(y)[0]
And then:
zip(ii,y[ii])
# [(1, 5), (2, 3), (5, 1), (25, 1)]
or:
np.vstack((ii,y[ii])).T
# array([[ 1, 5],
[ 2, 3],
[ 5, 1],
[25, 1]])
or however you want to combine the counts and the uni...