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Co-variant array conversion from x to y may cause run-time exception
...js[0] = new Foo(); // again legal, with runtime exception
In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...
HashSet versus Dictionary w.r.t searching time to find if an item exists
...s for Dictionary is so fast that there is no benefit from using HashSet at all, in the OP's case.
– EtherDragon
Jul 27 '12 at 23:03
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Python: What OS am I running on?
...ion of Darwin that comes with Catalina 10.15.2: en.wikipedia.org/wiki/MacOS_Catalina#Release_history
– philshem
Aug 21 at 13:28
add a comment
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How do I print the type of a variable in Rust?
...r
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= note: expected type `()`
found type `{float}`
Or call an invalid method:
let mut my_number = 32.90;
my_number.what_is_this();
error[E0599]: no method named `what_is_this` found for type `{float}` in the current scope
--> src/main.rs:3:15
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3 | my_number.what_is_...
How to convert a string or integer to binary in Ruby?
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You would naturally use Integer#to_s(2), String#to_i(2) or "%b" in a real program, but, if you're interested in how the translation works, this method calculates the binary representation of a given integer using basic operators:
def int_t...
How to convert a SVG to a PNG with ImageMagick?
... to convert it into a PNG, then I get a 16x16 pixel PNG which is way too small:
18 Answers
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Eclipse - Unable to install breakpoint due to missing line number attributes
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The above didn't work for me. I had to click the 'Remove all Breakpoints' icon in the Eclipse > Breakpoints view, then re-add the breakpoints. That worked.
– Vik David
May 19 '11 at 14:05
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How can I copy the output of a command directly into my clipboard?
... down the complete procedure just in case anyone else needs it.
First install a 16 kB program called xclip:
sudo apt-get install xclip
You can then pipe the output into xclip to be copied into the clipboard:
cat file | xclip
To paste the text you just copied, you shall use:
xclip -o
To si...
check if variable is dataframe
...rame
Yes: isinstance(x, pd.DataFrame)
And don't even think about
if obj.__class__.__name__ = 'DataFrame':
expect_problems_some_day()
isinstance handles inheritance (see What are the differences between type() and isinstance()?). For example, it will tell you if a variable is a string (eithe...
OnCreateOptionsMenu() not called in Fragment
I have an app which got one activity with 2 fragments placed horizontally.
8 Answers
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