function

问题 This is my first Bash script. I have a WiFi issue with my Debian machine. I'm not here to ask about the cause, but rather how to put a band-aid on the issue with Bash. My WiFi will drop out at a random time, usually every 12-15 minutes. I use SSH on this server, and do not want to have to run ifdown wlan0 and ifup wlan0 (which reconnects the WiFi) manually from the physical server. The function of this Bash script is to attempt to connect three times. If it fails three times, it will give up.

问题 This is my first Bash script. I have a WiFi issue with my Debian machine. I'm not here to ask about the cause, but rather how to put a band-aid on the issue with Bash. My WiFi will drop out at a random time, usually every 12-15 minutes. I use SSH on this server, and do not want to have to run ifdown wlan0 and ifup wlan0 (which reconnects the WiFi) manually from the physical server. The function of this Bash script is to attempt to connect three times. If it fails three times, it will give up.

问题 I trying to learn OOP and I've made this class class boo{ function boo(&another_class, $some_normal_variable){ $some_normal_variable = $another_class->do_something(); } function do_stuff(){ // how can I access '$another_class' and '$some_normal_variable' here? return $another_class->get($some_normal_variable); } } and I call this somewhere inside the another_class class like $bla = new boo($bla, $foo); echo $bla->do_stuff(); But I don't know how to access $bla, $foo inside the do_stuff

问题 I trying to learn OOP and I've made this class class boo{ function boo(&another_class, $some_normal_variable){ $some_normal_variable = $another_class->do_something(); } function do_stuff(){ // how can I access '$another_class' and '$some_normal_variable' here? return $another_class->get($some_normal_variable); } } and I call this somewhere inside the another_class class like $bla = new boo($bla, $foo); echo $bla->do_stuff(); But I don't know how to access $bla, $foo inside the do_stuff

问题 I trying to learn OOP and I've made this class class boo{ function boo(&another_class, $some_normal_variable){ $some_normal_variable = $another_class->do_something(); } function do_stuff(){ // how can I access '$another_class' and '$some_normal_variable' here? return $another_class->get($some_normal_variable); } } and I call this somewhere inside the another_class class like $bla = new boo($bla, $foo); echo $bla->do_stuff(); But I don't know how to access $bla, $foo inside the do_stuff

问题 Suppose we have an R function whose arguments must be selected out of a finite set of elements. Like qplot(..., geom="") . And geom can take only some values, like bar or point . How can I find out all the valid values the argument of a given function may take? Apart from docs or Internet, which often miss all possible values. Perhaps, some R function can help? 回答1: If the function of interest is defined like f <- function(a = c("foo","bar")) { match.arg(a) } i.e. when the options are defined

问题 Is the return statement the last statement inside main or is it possible to write statements after return? #include <iostream> using namespace std; int main() { cout << "Hello" << endl; return 0; cout << "Bye" << endl; } This program compiles but only displays "Hello". 回答1: is it possible to write statements after return? It is possible and valid to write more statements after the return. With gcc and Clang, I don't get a warning, even with the -Wall switch. But Visual Studio does produce

问题 Is the return statement the last statement inside main or is it possible to write statements after return? #include <iostream> using namespace std; int main() { cout << "Hello" << endl; return 0; cout << "Bye" << endl; } This program compiles but only displays "Hello". 回答1: is it possible to write statements after return? It is possible and valid to write more statements after the return. With gcc and Clang, I don't get a warning, even with the -Wall switch. But Visual Studio does produce

问题 I'm trying to create a code that counts the number of positive and negative numbers from a given array using a function. For example in the array {-1, 2, -3, 4.5 , 0, .3, -999.99} it's supposed to show 2 positive numbers, and 4 negative numbers and excludes the number 0. I'm using two counters to keep track of how many negative and positive numbers, a for loop to cycle through the array, but I don't know how to incorporate the boolean parameter when true or false is called on to display the

问题 I'm trying to create a code that counts the number of positive and negative numbers from a given array using a function. For example in the array {-1, 2, -3, 4.5 , 0, .3, -999.99} it's supposed to show 2 positive numbers, and 4 negative numbers and excludes the number 0. I'm using two counters to keep track of how many negative and positive numbers, a for loop to cycle through the array, but I don't know how to incorporate the boolean parameter when true or false is called on to display the