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Is a Python dictionary an example of a hash table?
...le. You can read a description of python's dict implementation, as written by Tim Peters, here.
That's why you can't use something 'not hashable' as a dict key, like a list:
>>> a = {}
>>> b = ['some', 'list']
>>> hash(b)
Traceback (most recent call last):
File "<st...
How do I temporarily disable triggers in PostgreSQL?
...e all trigger modifications much more cheaply after the fact than on a row-by-row basis.
6 Answers
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How to convert String to long in Java?
... a simple question in Java: How can I convert a String that was obtained by Long.toString() to long ?
9 Answers
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AttributeError(“'str' object has no attribute 'read'”)
... so it must happen in the json.load function that you called (as indicated by the full traceback). That is because json.load is trying to .read the thing that you gave it, but you gave it jsonofabitch, which currently names a string (which you created by calling .read on the response).
Solution: do...
Increase number of axis ticks
...
You can override ggplots default scales by modifying scale_x_continuous and/or scale_y_continuous. For example:
library(ggplot2)
dat <- data.frame(x = rnorm(100), y = rnorm(100))
ggplot(dat, aes(x,y)) +
geom_point()
Gives you this:
And overriding the sc...
The server committed a protocol violation. Section=ResponseStatusLine ERROR
...
anyone know why this safety measure is imposed by IIS? It worked, but I don't understand the reason for the restriction on header values (manually setting them in my case).
– emran
Feb 19 '14 at 5:20
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Scanner vs. StringTokenizer vs. String.Split
...give you the simplest API for simply getting an array of strings delimited by a particular expression.
String.split() and Pattern.split() give you an easy syntax for doing the latter, but that's essentially all that they do. If you want to parse the resulting strings, or change the delimiter halfway...
Disable same origin policy in Chrome
...
From the chromium source:
// Don't enforce the same-origin policy. (Used by people testing their sites.)
const wchar_t kDisableWebSecurity[] = L"disable-web-security";
Before Chrome 48, you could just use:
chromium-browser --disable-web-security
...
Error during SSL Handshake with remote server
...
The comment by MK pointed me in the right direction.
In the case of Apache 2.4 and up, there are different defaults and a new directive.
I am running Apache 2.4.6, and I had to add the following directives to get it working:
SSLProxyE...
Scala how can I count the number of occurrences in a list
...ple", "oranges", "apple", "banana", "apple", "oranges", "oranges")
s.groupBy(identity).mapValues(_.size)
giving a Map with a count for each item in the original sequence:
Map(banana -> 1, oranges -> 3, apple -> 3)
The question asks how to find the count of a specific item. With this a...