conditional-statements

问题 For the following data, mydata ID Y x z 1 1 5.302956 1 1 2 1 3.358249 2 1 3 1 4.976734 3 1 4 1 4.290459 4 1 5 1 0.000000 5 0 6 2 5.975351 1 1 7 2 6.620773 2 1 8 2 8.045909 3 1 9 2 7.378384 4 1 10 2 6.908755 5 1 11 2 8.672657 6 1 12 2 8.284252 7 1 13 2 8.455531 8 1 14 2 7.415175 9 1 15 2 8.634265 10 1 16 3 7.356993 1 1 17 3 6.607598 2 1 18 3 0.000000 3 0 19 3 0.000000 4 0 20 3 0.000000 5 0 21 3 0.000000 6 0 22 3 0.000000 7 0 23 3 0.000000 8 0 24 3 6.398595 9 1 25 3 6.580639 10 1 26 4 5.525104

问题 I have this formula, I wanted to turn this into pandas calculation, the formula is very easy: NEW = A(where v=1) + A(where v=3) + A(where v=5) I have a data frame like this: Type subType value A NEW X a 1 3 =3+9+9=21 X a 3 9 X a 5 9 X b 1 4 =4+5+0=9 X b 3 5 X b 5 0 Y a 1 1 =1+2+3=6 Y a 3 2 Y a 5 3 Y b 1 4 =4+5+2=11 Y b 3 5 Y b 5 2 Two questions: I know I can just write down the calculation with the specified cell, but I want the code looks nicer, is there other ways to get the value? Because

问题 Suppose I have the following column vectors as res1 = -0.81 res2 = 0.61 0.1 -0.4 -0.91 0.62 0.2 -0.56 0.63 -0.72 and I have two fixed constant D = 0.5 . Now suppose an element of res1 is called X and an element of res2 is called Y . I have the following conditions if (X > D && Y < -D) output = 1 elseif (X < -D && Y > D) output = -1 else output = 0 end My question is this: Is it possible to "vectorize" these conditions to iterate over the entire vectors res1 and res2 , such that my output

问题 Suppose I have the following column vectors as res1 = -0.81 res2 = 0.61 0.1 -0.4 -0.91 0.62 0.2 -0.56 0.63 -0.72 and I have two fixed constant D = 0.5 . Now suppose an element of res1 is called X and an element of res2 is called Y . I have the following conditions if (X > D && Y < -D) output = 1 elseif (X < -D && Y > D) output = -1 else output = 0 end My question is this: Is it possible to "vectorize" these conditions to iterate over the entire vectors res1 and res2 , such that my output

问题 I am trying to do a check before the data inserts into the MySQL query. Here is the code; $userid = ($vbulletin->userinfo['userid']); $sql3 = mysql_query("SELECT * FROM table WHERE ID='$_POST[hiddenID]'"); while ($row = mysql_fetch_array($sql3)){ $toon = $row['toonname']; $laff = $row['tlaff']; $type = $row['ttype']; if ($type == 1){ $type == "Bear"; } elseif ($type == 2){ $type == "Cat"; } elseif ($type == 3){ $type == "Dog"; } } However, this isn't working. Basically, there are different

问题 I have two matrices a and b (with equal number of columns). I want to create a third matrix c using a condition: For example, I have: a = [1 2 3 4 1 2 3 4 1 2 3 4; 1 1 1 1 2 2 2 2 3 3 3 3] b = [5 6 7 8 9 10 11 12 13 14 15 16; 17 18 19 20 21 22 23 24 25 26 27 28; 29 30 31 32 33 34 35 36 37 38 39 40] The condition is: a(2, :) == 2 , so the resulting matrix should be: c = [1 2 3 4; 2 2 2 2; 9 10 11 12; 21 22 23 24; 33 34 35 36] 回答1: Try this %With your a and b cols = a(2,:) == 2; c = [a(:,cols)

问题 I have two matrices a and b (with equal number of columns). I want to create a third matrix c using a condition: For example, I have: a = [1 2 3 4 1 2 3 4 1 2 3 4; 1 1 1 1 2 2 2 2 3 3 3 3] b = [5 6 7 8 9 10 11 12 13 14 15 16; 17 18 19 20 21 22 23 24 25 26 27 28; 29 30 31 32 33 34 35 36 37 38 39 40] The condition is: a(2, :) == 2 , so the resulting matrix should be: c = [1 2 3 4; 2 2 2 2; 9 10 11 12; 21 22 23 24; 33 34 35 36] 回答1: Try this %With your a and b cols = a(2,:) == 2; c = [a(:,cols)

问题 I have a data table with 4 columns: ID, Name, Rate1, Rate2. I want to remove duplicates where ID, Rate1, and Rate 2 are the same, but if they are both NA, I would like to keep both rows. Basically, I want to conditionally remove duplicates, but only if the conditions != NA. For example, I would like this: ID Name Rate1 Rate2 1 Xyz 1 2 1 Abc 1 2 2 Def NA NA 2 Lmn NA NA 3 Hij 3 5 3 Qrs 3 7 to become this: ID Name Rate1 Rate2 1 Xyz 1 2 2 Def NA NA 2 Lmn NA NA 3 Hij 3 5 3 Qrs 3 7 Thanks in

问题 I have a data table with 4 columns: ID, Name, Rate1, Rate2. I want to remove duplicates where ID, Rate1, and Rate 2 are the same, but if they are both NA, I would like to keep both rows. Basically, I want to conditionally remove duplicates, but only if the conditions != NA. For example, I would like this: ID Name Rate1 Rate2 1 Xyz 1 2 1 Abc 1 2 2 Def NA NA 2 Lmn NA NA 3 Hij 3 5 3 Qrs 3 7 to become this: ID Name Rate1 Rate2 1 Xyz 1 2 2 Def NA NA 2 Lmn NA NA 3 Hij 3 5 3 Qrs 3 7 Thanks in

问题 Something like this, I'd like to see the full syntax. Pseudo Code: var = user_input if var > 5: output = 'var > 5' else: output = 'var < 5' 回答1: How about something along the lines of: #include <stdio.h> #include <string.h> int main (void) { int var; char buff[100]; printf ("Enter number> "); fflush (stdout); if (fgets (buff, sizeof(buff), stdin) == NULL) { printf ("\nfgets() failed\n"); return 1; } if (sscanf (buff, "%d", &var) != 1) { printf ("\nsscanf() failed\n"); return 1; } if (var > 5)