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Length of an integer in Python
...conds. And Math.log10 method took only 7.486343383789062e-05 seconds, approximately 1501388 times faster!
– FadedCoder
Mar 19 '17 at 16:30
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Where can I learn how to write C code to speed up slow R functions? [closed]
...? I know about the system and foreign language interfaces section of R extensions, but I find it pretty hard going. What are good resources (both online and offline) for writing C code for use with R?
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Plotting time in Python with Matplotlib
..._demo1 link provided by J. K. Seppänen. The matplot lib documentation is excellent, BTW. matplotlib.sourceforge.net/index.html
– codeape
Oct 19 '09 at 13:53
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Detect if a NumPy array contains at least one non-numeric value?
...ce - the function should give the correct value regardless of ndim. As an extra complication the input could be a single float or numpy.float64 or even something oddball like a zero-dimensional array.
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What is the apply function in Scala?
...ling and verbing nouns ( an AddTwo class has an apply that adds two!) examples.
3 Answers
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C＋＋模板的特化 - C/C++ - 清泛网 - 专注C/C++及内核技术
...ue;
}
};
混合型的：
template<typename T1, typename T2>
class X {...};
template<typename T>
class X<vector<T>, int&> {...}; //至于这里怎么都把T2搞没了变成只依赖一个模板参数T了的问题，大家别着急，我来告诉你个本质的东西，把我这么三点...
Algorithm to return all combinations of k elements from n
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Reverse Y-Axis in PyPlot
I have a scatter plot graph with a bunch of random x, y coordinates. Currently the Y-Axis starts at 0 and goes up to the max value. I would like the Y-Axis to start at the max value and go up to 0.
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Is there a typical state machine implementation pattern?
...gram logic, run other state machines, etc
}
}
This can of course be extended to support multiple state machines, etc. Transition actions can be accommodated as well:
typedef void transition_func_t( instance_data_t *data );
void do_initial_to_foo( instance_data_t *data );
void do_foo_to_bar( ...
Remove duplicated rows using dplyr
...ginal answer below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: lo...