multidimensional-array

问题 I have an array that looks like this. var array[["a","b"],["c","d"],["e","f"]]; I want to be able to search through the array for the string "d" and return the corresponding value "c" . 回答1: try: function find_str(array){ for(var i in array){ if(array[i][1] == 'd'){ return array[i][0]; } } } EDIT: function find_str(array){ for(var i=0;i<array.length;i++){ if(array[i][1] == 'd'){ return array[i][0]; } } } 回答2: A general function for getting all the elements of the arrays that contain the

问题 I have two arrays: array1 = numpy.array([ 7.26741212e-01, -9.80825232e-17]) array2 = numpy.array([-3.82390578e-01, -1.48157964e-17], [-3.82390578e-01, 7.87310307e-01], [ 7.26741212e-01, -9.80825232e-17], [ 7.26741212e-01, -9.80825232e-17], [-3.82390578e-01, -2.06286905e-01], [ 7.26741212e-01, -9.80825232e-17], [-2.16887107e-01, 6.84509305e-17], [-3.82390578e-01, -5.81023402e-01], [-2.16887107e-01, 6.84509305e-17], [-2.16887107e-01, 6.84509305e-17]) How do I get the cosine distance of each row

问题 I'm trying to learn SQL but hitting a wall with the following problem. I can solve it easily using imperative programming but would like to know if it's possible to solve this problem using just a query: Input Table 1 (users) ID | Firstname -------------- 1 | Felix 2 | Michael 3 | Tobias Table 2 (hobbies) ID | Hobby | User ------------------------ 1 | cooking | 1 2 | cat | 1 3 | piano | 2 Wanted Output { "users": [{ "firstname": "Felix", "hobbies": [{ "id": 1, "name": "cooking" }, { "id": 2,

问题 Hey I'm having trouble understanding on how structs get passed to functions as pointers because i want to modify my structs later in my project. So I'm creating a game that has rooms and this function creates a 2d array of the world. I'm passing in struct room and struct World because I'm storing each room in a cord in World struct which is a 2d array. When i got print out each room, it doesn't print anything out and i think the problem is with my pointers. So my first function that's in a

问题 Im stil a beginner in C programming and I need a little help writing a code for my C programming class . The prompt is: Input for this program is a two-dimensional array of floating point data located in a file named textfile94. The input array will contain 3 rows of data with each row containing 5 columns of data. I want you to use the two-subscript method of dynamic memory allocation. Use malloc to create an array that holds pointers. Each element of that array points at another array,

问题 I have the following recursive function, def subspaceiterate(A,V,v,j): if j == 0: return v else: v_jm1 = V[:,j-1] v_jm1 = np.reshape(v_jm1,(np.size(V,axis=0),1)) v = v - np.matmul(v_jm1.T,np.matmul(A,v_jm1)) j = j - 1 subspaceiterate(A,V,v,j) A is an mxm matrix whose eigenvalues and eigenvectors I want to compute using an iterative method, V is an mxm matrix that stores my initial guess for the eigenvectors of A , v_j is a particular column of V , and j is an index that I descend and use to

问题 I have the following recursive function, def subspaceiterate(A,V,v,j): if j == 0: return v else: v_jm1 = V[:,j-1] v_jm1 = np.reshape(v_jm1,(np.size(V,axis=0),1)) v = v - np.matmul(v_jm1.T,np.matmul(A,v_jm1)) j = j - 1 subspaceiterate(A,V,v,j) A is an mxm matrix whose eigenvalues and eigenvectors I want to compute using an iterative method, V is an mxm matrix that stores my initial guess for the eigenvectors of A , v_j is a particular column of V , and j is an index that I descend and use to

问题 So i am running into trouble while iterating through a string and inserting it's chars as index-arrays into a multidimensional,associative array. So basically a bunch of multidimensional arrays in multidimensional arrays in multidimensional arrays..... That is a bit troublesome as i cant do it by hand. I need an automated way to do this with a bunch of strings. The following example will explain it a bit better i think: //string i want to enter $string = 'ADAM'; //array i want to end up with

问题 I have this function that converts a flat array to a tree based on a path property. This is my data : const input = [ {"name":"brussels_district_north","path":"Brussels/Brussels CBD/North"}, {"name":"brussels_district_louise","path":"Brussels/Brussels CBD/Louise"}, {"name":"brussels_district_west","path":"Brussels/Brussels Decentralised/West"}, {"name":"brussels_district_léopold","path":"Brussels/Brussels CBD/Léopold"}, {"name":"brussels_district_airport","path":"Brussels/Brussels Periphery

问题 I have this function that converts a flat array to a tree based on a path property. This is my data : const input = [ {"name":"brussels_district_north","path":"Brussels/Brussels CBD/North"}, {"name":"brussels_district_louise","path":"Brussels/Brussels CBD/Louise"}, {"name":"brussels_district_west","path":"Brussels/Brussels Decentralised/West"}, {"name":"brussels_district_léopold","path":"Brussels/Brussels CBD/Léopold"}, {"name":"brussels_district_airport","path":"Brussels/Brussels Periphery