loops

问题 EDITED: I have a code which looks like: __author__ = 'feynman' cimport cython @cython.boundscheck(False) @cython.wraparound(False) @cython.nonecheck(False) def MC_Surface(volume, mc_vol): Perm_area = { "00000000": 0.000000, "11111111": 0.000000, ... ... "11100010": 1.515500, "00011101": 1.515500 } cdef int j, i, k for k in range(volume.shape[2] - 1): for j in range(volume.shape[1] - 1): for i in range(volume.shape[0] - 1): pattern = '%i%i%i%i%i%i%i%i' % ( volume[i, j, k], volume[i, j + 1, k],

问题 I have a dataframe df with 6 fields A,B,C,D,E & F. My requirement is to create a new column G which is equal to the previous value(C) + previous value(D) + previous (G) - F. But this needs to be implemented at a group level through columns A & B (group by A & B). In case it is the first row within the group then the value in column G should be equal to E. Sample Df - A B C D E F 1 2 100 200 300 0 1 2 110 210 310 10 1 2 120 130 300 10 1 1 140 150 80 0 1 1 50 60 80 20 1 1 50 60 80 20 Output - A

问题 I understand that it's removing the first 3 elements of the array and adding them to the new array. But how does the function continue to add ensuing chunks of the array to the new array variable? How does the while loop work without proper conditions? How does it work in collaboration with splice() here? function chunkArrayInGroups(arr, size){ let newArr = []; while(arr.length){ newArr.push(arr.splice(0, size)) } return newArr; } chunkArrayInGroups(["a", "b", "c", "d"], 2); 回答1: The

问题 for( i=0, i<3, i=i+1 ) for( i=0; i<4; i++ ) I do not understand why they are same. for( i=0, i<3, i=i+1 ) will start with i=0, then i=0+1=1, i=1+1=2, i=2+1=3, then 3 is not satisfied with i<3, then should close. So in the end, it repeats only 3 times isn't it? (i=0, 1, 2) for( i=0; i<4; i++ ) will start with i=0, then i=1, i=2, i=3, when reach i=4, 4 is not satisfied with i<4, then should close. So in the end, it repeats 4 times (i=0, 1, 2, 3). Am I wrong? 回答1: This for( i=0, i<3, i=i+1 ) is

问题 for( i=0, i<3, i=i+1 ) for( i=0; i<4; i++ ) I do not understand why they are same. for( i=0, i<3, i=i+1 ) will start with i=0, then i=0+1=1, i=1+1=2, i=2+1=3, then 3 is not satisfied with i<3, then should close. So in the end, it repeats only 3 times isn't it? (i=0, 1, 2) for( i=0; i<4; i++ ) will start with i=0, then i=1, i=2, i=3, when reach i=4, 4 is not satisfied with i<4, then should close. So in the end, it repeats 4 times (i=0, 1, 2, 3). Am I wrong? 回答1: This for( i=0, i<3, i=i+1 ) is

问题 I am relatively new to C, but I have been programming for a few years now. I am writing a program for a college class, and I am confused why the scanf function below is not called, resulting in an infinite loop. I have tried having my scanf outside the function, calling it twice, once from within, once from out, and a few other ways. I read online that the fflush might help, but it hasn't Any suggestions? // store starting variables int players; // print title printf("*-----------------------

问题 I am a new java programmer and I am writing a program that sets 3 model numbers for 3 printers. If user inputs wrong values I want it to continue asking user for the model number. I got it to work but only if the first value the user inters the the number for one of the 3 printers. if the first value is not one of the possible values and the second input is it still keeps repeating the loop. package printing; import java.util.Scanner; public class newClass { public static void main(String[]

问题 I came across a function where it had a setTimeout inside with a timeout growing exponentially (timeout *= 2) . let timeout = 10000 function foo() { // doSomething without breaking, returning setTimeout(foo, timeout) timeout *= 2; } foo() It seems that this should not be a problem and intuitively feels like setInterval is kinda doing the same already (having an infinite loop until it's cancelled if ever) , however, my question is in the approach itself. Is this something that could lead to

问题 I came across a function where it had a setTimeout inside with a timeout growing exponentially (timeout *= 2) . let timeout = 10000 function foo() { // doSomething without breaking, returning setTimeout(foo, timeout) timeout *= 2; } foo() It seems that this should not be a problem and intuitively feels like setInterval is kinda doing the same already (having an infinite loop until it's cancelled if ever) , however, my question is in the approach itself. Is this something that could lead to

问题 I have the following PHP array structure: $set = array(); $set[] = array('firstname'=>'firstname 1', 'lastname'=>'lastname 1', "bio"=>array('paragraph 1 of the bio, 'paragraph 2 of the bio','paragraph 3 of the bio'), ); I then access the array with the following: <?php $counter = 0; while ($counter < 1) : //1 for now $item = $set[$counter]?> <h1><?php echo $item['firstname'] ?></h1> <h1><?php echo $item['lastname'] ?></h1> <?php endwhile; ?> I'm uncertain how I can loop through the "bio" part