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How do I set a conditional breakpoint in gdb, when char* x points to a string whose value equals “he
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How do I get the row count of a pandas DataFrame?
...eturn non-NaN counts for each column:
df.count()
A 5
B 3
dtype: int64
For Series, use Series.count to similar effect:
s.count()
# 3
Group-wise Row Count: GroupBy.size
For DataFrames, use DataFrameGroupBy.size to count the number of rows per group.
df.groupby('A').size()
A
a 2
b ...
Benchmarking (python vs. c++ using BLAS) and (numpy)
...
CPU: 2 x 16 Intel(R) Xeon(R) E2560 Sandy Bridge @ 2.00GHz (16 Cores)
RAM: 64 GB
Ivy (MKL, OpenBLAS, ATLAS):
CPU: 2 x 20 Intel(R) Xeon(R) E2680 V2 Ivy Bridge @ 2.80GHz (20 Cores, with HT = 40 Cores)
RAM: 256 GB
Software
The software stack is for both nodes the sam. Instead of GotoBLAS2, OpenB...
Storing time-series data, relational or non?
...n is never a Key (duplicate rows, which are prohibited in a Relational database, must be prevented by other means).
The Id column requires an additional Index, which obviously impedes the speed of INSERT/DELETE, and adds to the disk space used.
You can get rid of it. Please.
Elevation
Now ...
AtomicInteger lazySet vs. set
...ite. There are a few
other use cases along these lines for non-reference-based
atomics as well, so the method is supported across all of the
AtomicX classes.
For people who like to think of these operations in terms of
machine-level barriers on common multiprocessors, lazySet
provides...
Why does using an Underscore character in a LIKE filter give me all the results?
...ess supports like operator. My solution will work in most, if not all, databases.
– Rachcha
Oct 25 '13 at 13:51
2
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vertical align middle in
...can use line-height: 50px;, you won't need vertical-align: middle; there.
Demo
The above will fail if you've multiple lines, so in that case you can wrap your text using span and than use display: table-cell; and display: table; along with vertical-align: middle;, also don't forget to use width:...
“Code too large” compilation error in Java
...
A single method in a Java class may be at most 64KB of bytecode.
But you should clean this up!
Use .properties file to store this data, and load it via java.util.Properties
You can do this by placing the .properties file on your classpath, and use:
Properties propert...
What is the difference between char array and char pointer in C?
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gsamaras
64.5k3131 gold badges140140 silver badges240240 bronze badges
answered Apr 17 '12 at 7:15
JonJon
...
Disable sorting for a particular column in jQuery DataTables
...mg src="https://www.gravatar.com/avatar/8edcff60cdcca2ad650758fa524d4990?s=64&amp;d=identicon&amp;r=PG" alt="" style="width: 64px; height: 64px; visibility: visible;"></td>
<td>2011/04/25</td>
<td>$320,800</td>
</tr>
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