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In Objective-C, how do I test the object type?
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If your object is myObject, and you want to test to see if it is an NSString, the code would be:
[myObject isKindOfClass:[NSString class]]
Likewise, if you wanted to test myObject for a UIImageView:
[myObject isKindOfClass:[UIImageView class]]
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How to get a value from a cell of a dataframe?
...ith only one row, then access the first (only) row as a Series using iloc, and then the value using the column name:
In [3]: sub_df
Out[3]:
A B
2 -0.133653 -0.030854
In [4]: sub_df.iloc[0]
Out[4]:
A -0.133653
B -0.030854
Name: 2, dtype: float64
In [5]: sub_df.iloc[0]['A']
Ou...
Assigning default values to shell variables with a single command in bash
... answered Jan 6 '10 at 14:36
Andrew McGregorAndrew McGregor
21.9k22 gold badges2525 silver badges2828 bronze badges
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makefile:4: *** missing separator. Stop
...relationship with tabs. All actions of every rule are identified by tabs. And, no, four spaces don't make a tab. Only a tab makes a tab.
To check, I use the command cat -e -t -v makefile_name.
It shows the presence of tabs with ^I and line endings with $. Both are vital to ensure that dependencie...
Why do std::shared_ptr work
...g delete). When the shared_ptr is destroyed, it calls that stored function and that will call the deleter.
A simple sketch of the type erasure that is going on simplified with std::function, and avoiding all reference counting and other issues can be seen here:
template <typename T>
void del...
Postgres could not connect to server
After I did brew update and brew upgrade, my postgres got some problem. I tried to uninstall postgres and install again, but it didn't work as well.
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Get color value programmatically when it's a reference (theme)
...o apply the theme to your Activity before calling this code. Either use:
android:theme="@style/Theme.BlueTheme"
in your manifest or call (before you call setContentView(int)):
setTheme(R.style.Theme_BlueTheme)
in onCreate().
I've tested it with your values and it worked perfectly.
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What is causing this error - “Fatal error: Unable to find local grunt”
...ed the old version of grunt first, then I installed the new grunt version, and then I got this error:
13 Answers
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How do I add 1 day to an NSDate?
... Yes works well for daylight savings. Tip for DST check: Reset date and time on your mac and then restart your simulator, it will then follow your system time.
– Rob van den Berg
Apr 1 '13 at 5:00
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How can I have grep not print out 'No such file or directory' errors?
I'm grepping through a large pile of code managed by git, and whenever I do a grep, I see piles and piles of messages of the form:
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