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Pandas DataFrame Groupby two columns and get counts
I have a pandas dataframe in the following format:
6 Answers
6
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Find nearest latitude/longitude with an SQL query
I have latitude and longitude and I want to pull the record from the database, which has nearest latitude and longitude by the distance, if that distance gets longer than specified one, then don't retrieve it.
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What's the purpose of the LEA instruction?
For me, it just seems like a funky MOV. What's its purpose and when should I use it?
16 Answers
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UIScrollView Scrollable Content Size Ambiguity
...le with AutoLayout in Interface Builder (Xcode 5 / iOS 7).
It's very basic and important so I think everyone should know how this properly works. If this is a bug in Xcode, it is a critical one!
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Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
... trade off memory for speed (assuming your L1 Data Cache is large enough), and reverse 16 bits at a time with a 64K-entry lookup table.
Others
Simple
unsigned int v; // input bits to be reversed
unsigned int r = v & 1; // r will be reversed bits of v; first get LSB of v
int s = sizeof(v...
What are the most common naming conventions in C?
...e GTK+ coding convention, which can be summarized as follows:
All macros and constants in caps: MAX_BUFFER_SIZE, TRACKING_ID_PREFIX.
Struct names and typedef's in camelcase: GtkWidget, TrackingOrder.
Functions that operate on structs: classic C style: gtk_widget_show(), tracking_order_process().
P...
Why do we need boxing and unboxing in C#?
Why do we need boxing and unboxing in C#?
11 Answers
11
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The difference between the Runnable and Callable interfaces in Java
What is the difference between using the Runnable and Callable interfaces when designing a concurrent thread in Java, why would you choose one over the other?
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Error in plot.new() : figure margins too large, Scatter plot
I've looked in different questions for a solution and I've tried what was suggested but I have not found a solution to make it work.
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How did I get a value larger than 8 bits in size from an 8-bit integer?
... occurs when the value is extended to bit-width sizeof(int) . As I understand it, incrementing a char shouldn't ever be undefined behavior as long as sizeof(char) < sizeof(int) . But that doesn't explain how c is getting an impossible value. As an 8-bit integer, how can c hold values gr...