ternary

问题 So the operator precedence of the ternary operator in C seems truly bizarre to me. Case in point: #include <stdio.h> int main () { int i=5; int j=6; int k=7; printf("A: %d\n", i+j+(k!=7)?1:11); //prints 1 printf("B: %d\n", i+j+((k!=7)?1:11)); //prints 22 return 0; } This seems similar to the question here: C++ ternary conditional and assignment operator precedence Ternary operator evaluation order As a clarification, I understand that the parentheses make it work, as my comments in my

问题 Is there a oneliner for this? A nice Ternary OP? $F_NAME = $_SESSION['USR']['F_NAME']; if(isset($_POST['F_NAME'])) {$F_NAME = $_POST['F_NAME'];} Basically "If the POST is sent, show that, even if the post is empty, otherwise grab the value from the session, but only if the post was not set or empty" Really splitting hairs here... looking for something like this: $F_NAME = ? ($F_NAME ? isset($_POST['F_NAME']) : $_SESSION['USR']['F_NAME']); 回答1: Its supposed to be: (conditions) ? true : false

问题 I need to evaluate a function (say) Fxy = 2*x.^2 +3 *y.^2; on a ternary grid x-range (0 - 1), y-range (0-1) and 1-x-y (0 - 1). I am unable to construct the ternary grid on which I need to evaluate the above function. Also, once evaluated I need to plot the function in a ternary contour plot. Ideally, I need the axes to go counter clockwise in the sense (x -> y--> (1-x-y)). I have tried the function function tg = triangle_grid ( n, t ) ng = ( ( n + 1 ) * ( n + 2 ) ) / 2; tg = zeros ( 2, ng );

问题 I need to evaluate a function (say) Fxy = 2*x.^2 +3 *y.^2; on a ternary grid x-range (0 - 1), y-range (0-1) and 1-x-y (0 - 1). I am unable to construct the ternary grid on which I need to evaluate the above function. Also, once evaluated I need to plot the function in a ternary contour plot. Ideally, I need the axes to go counter clockwise in the sense (x -> y--> (1-x-y)). I have tried the function function tg = triangle_grid ( n, t ) ng = ( ( n + 1 ) * ( n + 2 ) ) / 2; tg = zeros ( 2, ng );

问题 class Foo { public: explicit Foo(double item) : x(item) {} operator double() {return x*2.0;} private: double x; } double TernaryTest(Foo& item) { return some_condition ? item : 0; } Foo abc(3.05); double test = TernaryTest(abc); In the above example, why is test equal to 6 (instead of 6.1) if some_condition is true? Changing the code like below returns value of 6.1 double TernaryTest(Foo& item) { return some_condition ? item : 0.0; // note the change from 0 to 0.0 } It seems that (in the

问题 I have the following code and MPLABX XC8 compiler gives this error: error: expression is not assignable U1ERRIRbits.RXFOIF ? uart1.oerr = 1 : uart1.oerr = 0; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ Here is the relevant code section: typedef union { struct { bool ferr : 1; // FERIF Framing Error bool aerr : 1; // ABDOVF Error bool oerr : 1; // RXFOIF Error bool ready : 1; // Data Ready to be read uint8_t reserved : 4; }; uint8_t status; }uart1_status_t; static volatile uart1_status

问题 I'm learning about ternary operators now. I got the basics down, but then I saw this snippet and it doesn't make any sense to me. Can anyone please explain how is it put together?! b.m & 4 || (c |= 2, 63 <= a && 77 >= a ? a = 65 : 48 <= a && 57 >= a ? a = 48 : c & 1 ? 97 <= a && 122 >= a ? a = 65 : 197 == a || 229 == a ? c &= 5 : 192 <= a && 687 >= a ? a = 192 : 1536 <= a ? a = 1536 : 912 <= a ? a = 912 : 160 <= a ? a = 160 : 127 <= a ? c &= 5 : 33 <= a ? a = 59 : c &= 5 : 48 > a ? c &= 5 :

问题 Is ternary iteration possible? A simplistic version of what I mean, though this particular example could be done in a better way: c = 0 list1 = [4, 6, 7, 3, 4, 5, 3, 4] c += 1 if 4 == i for i in list1 else 0 A more practical example: strList = ['Ulis', 'Tolus', 'Utah', 'Ralf', 'Chair'] counter = 0 counter += 1 if True == i.startswith('U') for i in strList else 0 return counter 回答1: Your "practical example" is written as: >>> strList = ['Ulis', 'Tolus', 'Utah', 'Ralf', 'Chair'] >>> sum(1 for

问题 This question already has answers here : Returning null as an int permitted with ternary operator but not if statement (8 answers) Closed 2 years ago . The following (logically) is a compile-time error: public int myMethod(MyObject input) { if (input == null) { return null; // compiler says I cannot return null for primitive type } else { return 1; } } So far so good. What I don't understand, that the following is allowed: public int myMethod(MyObject input) { return input == null ? null : 1;

问题 I'm currently having some trouble understanding ternary associations in UML. I get the binary ones, but I am unsure how multiplicity works on ternary. I'm doing exercises that I got from my university, the current one goes like this: One department may sell many products, but only to one market. On a market one product may only be sold by one department. I've read on different sources about how I'm supposed to think about a pair of the two classes I'm not trying to figure out the multiplicity