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Selecting/excluding sets of columns in pandas [duplicate]
...ed OR Select the ones you need
# Using DataFrame.drop
df.drop(df.columns[[1, 2]], axis=1, inplace=True)
# drop by Name
df1 = df1.drop(['B', 'C'], axis=1)
# Select the ones you want
df1 = df[['a','d']]
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Where is the “Fold” LINQ Extension Method?
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127
You will want to use the Aggregate extension method:
double product = doubles.Aggregate(1.0, ...
JNI converting jstring to char *
...wikipedia.org/wiki/Java_Native_Interface
http://download.oracle.com/javase/1.5.0/docs/guide/jni/spec/functions.html
concerning your problem you can use this
JNIEXPORT void JNICALL Java_ClassName_MethodName(JNIEnv *env, jobject obj, jstring javaString)
{
const char *nativeString = env->Ge...
Programmer Puzzle: Encoding a chess board state throughout a game
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31 Answers
31
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std::shared_ptr thread safety explained
...e only newly created object?
is incorrect. Only d will point to the new A(10), and a, b, and c will continue to point to the original A(1). This can be seen clearly in the following short example.
#include <memory>
#include <iostream>
using namespace std;
struct A
{
int a;
A(int a)...
R apply function with multiple parameters
I have a function f(var1, var2) in R. Suppose we set var2 = 1 and now I want to apply the function f() to the list L . Basically I want to get a new list L* with the outputs
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Python list iterator behavior and next(iterator)
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199
What you see is the interpreter echoing back the return value of next() in addition to i being...
How to get image height and width using java?
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13 Answers
13
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How to import local packages without gopath
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179
Go dependency management summary:
vgo if your go version is: x >= go 1.11
dep or vendor i...