conditional-statements

问题 Really having some trouble even phrasing the problem. What's happening is I'm reading and storing an entire binary file into a uint32_t*. Then checking for the start of the segment of data I need. However, adding a check to just make sure I haven't passed over the array changes where the start of the segment is and I have no idea why. #include <iostream> #include <string.h> #include <typeinfo> #include <fstream> #include <vector> #include <stdint.h> #include <stdexcept> using namespace std;

问题 I am trying to run a left join on 2 tables. I do not have a group by and the only where condition i have is on the second table. But, the returned rows are less than the first table. isn't the left join suppose to bring all the data from the first table? Here is my SQL: select * from tbl_a A left join tbl_b B ON A.Cnumber=B.Cnumber and A.CDNUmber=B.CDNumber and abs(A.duration - B.Duration)<2 and substr(A.text,1,3)||substr(A.text,5,8)||substr(A.text,9,2)=substr(B.text,1,8) where B.fixed =

问题 This question was migrated from Code Review Stack Exchange because it can be answered on Stack Overflow. Migrated 4 years ago . if 'force' in kwargs and kwargs['force'] is True: It feels like there should be a better way of writing this condition since I'm repeating both the key and variable. 回答1: While @EmanuelePaolini provided a great answer, there's another thing that I want to nitpick. You don't need to to check if something is true. For example, your code block would become this: if

问题 I am trying to build a small cms to test CakePHP 2.x In my PagesController (for displaying single sites), I use this code: $page = $this->Page->findByNavtitle($name, array( 'conditions' => array( 'Page.visible' => '1', ), ) ); The result should only set when the record is marked as visible. But this codeblock throws an error. The API describes, that just one parameter is allowed in these findBy magic methods. How can I get the result with conditions? 回答1: You cannot add conditions to findBy

问题 I have a table called Absence which records periods of Staff absence from work CREATE TABLE Absence ( absence_id_pk varchar(6) NOT NULL, staff_id_fk varchar(6), start_date date, end_date date, reason varchar(30), PRIMARY KEY (absence_id_pk), FOREIGN KEY (staff_id_fk) REFERENCES Full_Time_Employee(staff_id_fk) ); and I have created a view to count the total number of days an employee has been absent like so: CREATE VIEW employee_absence AS SELECT staff_id_pk, staff.first_name, staff.last_name,

问题 I am in a soup. The idea may be bad but i do need a solution. I have two condition variable, say A and B. Threads 1, 2 and 3 are waiting on A. Thread 4 is waiting on B. B will be pthread_cond-signal() by thread 2, that is thread 4 will be signaled to wake up by thread 2. Now, I have another thread 5 which pthread_cond_broadcasts() on condition variable A. I need all threads 1, 2 and 3 to wake up before thread 4 wakes up. That is say if thread 2 wakes up and signals on B thread 4 may wake up

问题 I have a dataframe with two columns ID and Activity. The activity is either 0 or 1. I want a new column containing a increasing number since the last activity was 1. However, the count should only be within one group (ID). If the activity is 1, the counting column should be reset to 0 and the count starts again. So, I have a dataframe containing the following: What is want is this: Can someone help me? 回答1: We using a new para 'G' here df['G']=df.groupby('ID').Activeity.apply(lambda x :(x

问题 I have this data M1 M2 M3 UCL 1 2 3 1.5 I would like to make new columns with this condition: If M1 is more than UCL, MM1 will be "UP" and otherwise "NULL" If M2 is more than UCL, MM2 will be "UP" and otherwise "NULL" If M3 is more than UCL, MM3 will be "UP" and otherwise "NULL" M1 M2 M3 UCL | MM1 MM2 MM3 1 2 3 1.5 | NULL UP UP But I have several M column (like M1~M1005) so that I would like to make some code such as mutate_each and mutate_at. How do I use the function using mutate and ifelse

问题 I have a (very simplyfied here) pandas dataframe which looks like this: df datetime user type msg 0 2012-11-11 15:41:08 u1 txt hello world 1 2012-11-11 15:41:11 u2 txt hello world 2 2012-11-21 17:00:08 u3 txt hello world 3 2012-11-22 18:08:35 u4 txt hello you 4 2012-11-22 18:08:37 u5 txt hello you What I would like to do now is to get all the duplicate messages which have their timestamp within 3 seconds . The desired output would be: datetime user type msg 0 2012-11-11 15:41:08 u1 txt hello

问题 Another follow up to this and this. Actual question Question 1 Upon running into some condition (say a simpleError ), how can I invoke a respective restart handler that systematically tests a range of actual handler functions until one is found that does not result in another condition? If the last available handler has been tried, the default abortion restart handler should be invoked ( invokeRestart("abort") ). The implementation should allow for a flexible specification of the actual