shift

问题 I am trying to figure the best way to differeniate in Perl between cases where an argument has not been passed, and where an argument has been passed as 0, since they mean different things to me. (Normally I like the ambiguity, but in this case I'm generating SQL so I want to replace undefined args with NULL, but leave 0 as 0.) So this is the ambiguity: sub mysub { my $arg1 = shift; if ($arg1){ print "arg1 could have been 0 or it could have not been passed."; } } And so far, this is my best

问题 I have a numpy array, for example a = np.arange(10) how can I move the first n elements to the end of the array? I found this roll function but it seems like it only does the opposite, which shifts the last n elements to the beginning. 回答1: Why not just roll with a negative number? >>> import numpy as np >>> a = np.arange(10) >>> np.roll(a,2) array([8, 9, 0, 1, 2, 3, 4, 5, 6, 7]) >>> np.roll(a,-2) array([2, 3, 4, 5, 6, 7, 8, 9, 0, 1]) 回答2: you can use negative shift a = np.arange(10) print(np

问题 This is what I have: class encoded { public static void main(String[] args) { String s1 = "hello"; char[] ch = s1.toCharArray(); for(int i=0;i<ch.length;i++) { char c = (char) (((i - 'a' + 1) % 26) + 'a'); System.out.print(c); } } } So far I've converted the string to an array, and I've worked out how to shift, but now I'm stuck. What I want is for the code to start at ch[0] , read the character, shift it one to the right ( h to i ) and then do the same for each character in the array until

问题 So I know this sounds like a duplicate, but it isn't (or if it is, the accepted answer on all the ones I can find doesn't work the way I need it to). The issue is this: I'm writing in HTML5 using jQuery, I need to make a grid allow multi-select with control and shift. I have that logic working, but whenever you shift-click it selects the text in the grid. I want to prevent this selection, but here's the critical difference between this and the other questions I found: I want selection of text

问题 I want to create a 64-bit barrel shifter in verilog (rotate right for now). I want to know if there is a way to do it without writing a 65 part case statement? Is there a way to write some simple code such as: Y = {S[i - 1:0], S[63:i]}; I tried the code above in Xilinx and get an error: i is not a constant. Main Question: Is there a way to do this without a huge case statment? 回答1: I've simplified some of the rules for clarity, but here are the details. In the statement Y = {S[i - 1:0], S[63

问题 I am trying to create a spec that will take input abc:true abc: {strings ...} and output: abc:true abc: {strings ...} I know this shouldn't require a Jolt shift, I just have to include it so that segment of my data (both abc keys) transfers over and doesn't get lost, Does anyone know what to add to a Jolt shift spec to do this ( shift 2 duplicate keys based on their value types ). 回答1: For the jolt processor, when you try to add key mappings that are already existing, the application will

问题 I am trying to optimize some code that I have written as it is very slow for large datasets. I am not sure if the following can be done with matrix operations and I would appreciate if someone had any suggestions to make it faster. I have a matrix with zeros and integers and I would like to shift down the entries of the individual columns by the absolute number of the integer in the the entry. [,1] [,2] [,3] [1,] 0 0 0 [2,] 0 -4 0 [3,] 4 0 0 [4,] -3 -2 0 [5,] 0 2 -1 [6,] 2 -2 0 [7,] 0 0 0 [8,

问题 I'm trying to create a different actionPerformed when Shift is held down while pressing a JButton, but when I use: event.isShiftDown; my program does not compile because it does't recognise it. 回答1: Basically you need to bitwise-and the ActionEvent#getModifiers result if ((e.getModifiers() & InputEvent.SHIFT_MASK) != 0) { // Shift is down... } 回答2: As an alternative to checking the event modifiers directly, consider using a different Action for each state of the shift key. You can supply the

问题 I have a dataframe (df) with 2 columns and 1 index. Index is datetime index and is in format of 2001-01-30 .... etc and the index is ordered by DATE and there are thousands of identical dates (and is monthly dates). Column A is company name (which corresponds to the date), Column B are share prices for the company names in column A for the date in the Index. Now there are multiple companies in Column A for each date, and companies do vary over time (so the data is not predictable fully). I

问题 Some help on... how to make it possible when shift is pressed, then the system automatically released it in split second, hence even though it is still pressed in the keyboard by the user, but the vb.net system already released the shift key? to avoid long press or hold on the key... I'm so out of idea already, hence decided to post a question here after doing some serious researches, please respond if you know some tricks to make this possible... 回答1: You can handle KeyDown event and check