negative

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I am newbie in Perl and I am reading about arrays. As I understand the arrays expand automatically as needed (cool!) But I also read that we can use negative indexes to access the arrays in reverse order. E.g. an array of 3 elements can be accessed as: $array[0] $array[1] $array[2] or $array[-1] $array[-2] $array[-3] (in reverse order). My question is what happens for values smaller than -3 e.g. $array[-5] ? Does the array expand or something? 回答1: If you read it, the result is the same as reading $array[5] ― the value doesn't exist and you

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I am trying to follow the udacity tutorial on tensorflow where I came across the following two lines for word embedding models: # Look up embeddings for inputs. embed = tf.nn.embedding_lookup(embeddings, train_dataset) # Compute the softmax loss, using a sample of the negative labels each time. loss = tf.reduce_mean(tf.nn.sampled_softmax_loss(softmax_weights, softmax_biases, embed, train_labels, num_sampled, vocabulary_size)) Now I understand that the second statement is for sampling negative labels. But the question is how does it know what

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: I Learned About 2's Complement and unsigned and signed int. So I Decided to test my knowledge , as far as i know that a negative number is stored in 2's complement way so that addition and subtraction would not have different algorithm and circuitry would be simple. Now If I Write int main () { int a = - 1 ; unsigned int b = - 1 ; printf ( "%d %u \n %d %u" , a , a , b , b ); } Output Comes To Be -1 4294967295 -1 4294967295 . Now , i looked at the bit pattern and various things and then i realized that -1 in 2's complement is

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I know that the behavior of >> on signed integer can be implementation dependent (specifically, when the left operand is negative). What about the others: ~ , >> , & , ^ , | ? When their operands are signed integers of built-in type ( short , int , long , long long ), are the results guaranteed to be the same (in terms of bit content) as if their type is unsigned? 回答1: For negative operands, has undefined behavior and the result of >> is implementation-defined (usually as "arithmetic" right shift). and >> are conceptually not bitwise

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: When I tried this in terminal >>> (-3.66/26.32)**0.2 I got the following error Traceback (most recent call last): File "<stdin>", line 1, in <module> ValueError: negative number cannot be raised to a fractional power However, I am able to do this in two steps like, >>> (-3.66/26.32) -0.13905775075987842 >>> -0.13905775075987842 ** 0.2 -0.6739676327771593 Why this behaviour? What is the way to solve this in single line? 回答1: Raising to a power takes precedence over the unary minus sign. So you have -(0.13905775075987842 ** 0.2) and not (-0

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: We all know about the maximum sum subarray and the famous Kadane's algorithm . But can we use the same algorithm to find minimum sum also? My take is: change the sign and find the max sum in that, same as the way we calculate the maximum sum subarray. Than change the sign of the elements in the array to make it in initial state. Please help me in correcting the algo if it has any issue. corner case: I know there is an issue if all the elements are positive and we can handle this case by doing some preprocessing i.e. traverse the array if all

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I am trying to understand why Dijkstra's algorithm will not work with negative weights. Reading an example on Shortest Paths , I am trying to figure out the following scenario: 2 A-------B \ / 3 \ / -2 \ / C From the website: Assuming the edges are all directed from left to right, If we start with A, Dijkstra's algorithm will choose the edge (A,x) minimizing d(A,A)+length(edge), namely (A,B). It then sets d(A,B)=2 and chooses another edge (y,C) minimizing d(A,y)+d(y,C); the only choice is (A,C) and it sets d(A,C)=3. But it never finds the

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: What exactly happens here? a Obviously it doesn't right shift. But the book I'm reading states: On one machine, this expression actually does a left shift of 27 bits My question is; why? What causes a left shift of 27 bits? And what exactly happens when shifting with a negative shift count? Thank you. 回答1: Negative integers on right-hand side is undefined behavior in the C language. ISO 9899:1999 6.5.7 Bit-wise shift operators §3 The integer promotions are performed on each of the operands. The type of the result is that of the promoted left

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: One of my pet hates of C-derived languages (as a mathematician) is that (-1) % 8 // comes out as -1, and not 7 fmodf(-1,8) // fails similarly What's the best solution? C++ allows the possibility of templates and operator overloading, but both of these are murky waters for me. examples gratefully received. 回答1: First of all I'd like to note that you cannot even rely on the fact that (-1) % 8 == -1 . the only thing you can rely on is that (x / y) * y + ( x % y) == x . However whether or not the remainder is negative is implementation-defined .

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I want to use a css3 transition to smooth a compass movement using phonegap. i calculate the desired rotation as angle from 0 to 359. The problem is, when it should go from for example 359 to 0 it doesn't turn 1 degree clockwise, but instead it turns 359 degree counter clockwise. Is there a way to tell css to always take the shortest way for a rotation? 回答1: The transform is doing exactly what you tell it to. It starts at 359deg and goes to 1deg. You are looking to 'rollover' 360deg back to 1deg, which is really 361deg. The way the transform