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Reading binary file and looping over each byte
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396
Python 2.4 and Earlier
f = open("myfile", "rb")
try:
byte = f.read(1)
while byte != "...
How to display unique records from a has_many through relationship?
...ay to display unique records from a has_many, through relationship in Rails3.
4 Answers
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What is the MySQL VARCHAR max size?
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300
Keep in mind that MySQL has a maximum row size limit
The internal representation of a MySQ...
Is MATLAB OOP slow or am I doing something wrong?
...ction/method 100000 times
nop() function: 0.02261 sec 0.23 usec per call
nop1-5() functions: 0.02182 sec 0.22 usec per call
nop() subfunction: 0.02244 sec 0.22 usec per call
@()[] anonymous function: 0.08461 sec 0.85 usec per call
nop(obj) metho...
Reshaping data.frame from wide to long format
...:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
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What are the differences between vector and list data types in R?
...tors are "atomic vectors" in strict R parlance:
aaa <- vector("list", 3)
is.list(aaa) #TRUE
is.vector(aaa) #TRUE
Lists are a "recursive" type (of vector) whereas atomic vectors are not:
is.recursive(aaa) # TRUE
is.atomic(aaa) # FALSE
You process data objects with different functions...
Python integer division yields float
...
Take a look at PEP-238: Changing the Division Operator
The // operator will be available to request floor division unambiguously.
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How to tell Maven to disregard SSL errors (and trusting all certs)?
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239
You can disable SSL certificate checking by adding one or more of these command line parameters...
How to use arguments from previous command?
...w see:
$ echo a
without pressing Enter yet, do the following
Press Alt-3 Alt-Ctrl-y
Press Alt-- 2 Alt-Ctrl-y
Now you will see:
$ echo ace
By the way, you could have put the echo on the line by selecting argument 0:
Press Alt-0 Alt-Ctrl-y
Edit:
To answer the question you added to your or...
What is more efficient? Using pow to square or just multiply it with itself?
... elapsed << " "; \
\
return x; \
}
TEST(1, b)
TEST(2, b*b)
TEST(3, b*b*b)
TEST(4, b*b*b*b)
TEST(5, b*b*b*b*b)
template <int exponent>
double testpow(double base, long loops)
{
double x = 0.0;
boost::posix_time::ptime startTime = now();
for (long i=0; i<loops; ++i)
...