conditional-statements

Once again, I apologize for asking this type of question, but the R world is so large that sometime I feel lost, even if I have read some of the best book related with R. I have the following DB ID=rep((1:3),3) x<-as.Date("2013-1-1") y<-as.Date("2013-1-2") z<-as.Date("2013-1-3") DATE<-c(x,x,x,y,x,y,z,z,z) TRAP<-c(1,1,1,3,2,3,2,1,3) IN<-data.frame(ID,DATE,TRAP) and I would like to produce a binary variable (RESULT) according to the following conditions: if the DATE and the TRAP is the same for the different ID, then RESULT>y otherwise RESULT>n, like this RESULT<-c("y","y","y","y","n","y","n","n

I am not sure if what I want to achieve is possible. So here it is: I got workbook with 2 sheets: First sheet cointains raw data with employees and trainings they did or did not take (they could not come to the the training). Sheets cointains few columns like: name, special ID (different for every employee), 2 blank columns, presence (yes/no), and few more... Second sheet will create report based on range and presence criteria. Technically it's something like that: Report sheet has list of employees, they will be filtered using autofilter. Those filtered employees will be checked if they were

I am writing a simple console program to help myself and some fellow geology students with rock sample analysis. Our lecturer provided us with a flow chart that helps to specify the characteristics of the sample. I am attempting to make this into a console program. My question is whether it is possible for the if statement on line 9 to take two conditions and if so have I written it correctly? def igneous_rock(self): print "Welcome to IgneousFlowChart" print "Assuming you are looking at an igneous rock, please choose the " print "option which best describes the sample:" print "1. Coherent 2.

So I declare a variable some where and initialize it. Now later on I need to use it to loop while its still positive so I need to decrement it. To me looping using a condition and a decrement calls for a for but for it we are missing the first part the initialization. But I don't need to initialize anything. So how do I go about that in a nice way. for (space = space; space > 0; space--)//my first way to do it but ide doesnt like it Second way: for (; space > 0; space--)//my friend recommended me this way but looks kind weird Are there more ways for me to have a loop with only condition and

Suppose I have an array. $array1 = array('John','Mike','Tim','Dan'); Using a foreach iteration, I'm looping through $array1 , performing a db query that returns either true or false so I have: foreach ($array1 as $key => $value) { $dbQueryResult = true; // or false depending on iteration if($dbQueryResult === true){ // HOW DO I CHECK IF IT IS THE FIRST TIME I'M GETTING HERE } } How do I check if it's the first time I'm getting a desired result in an if statement inside a foreach iteration like in the above example? Use a variable to keep that information in $firstTime = true; foreach ($array1

I have a large matrix, z, that I removed all values >3 and replaced with NA using: z[z>3]<-NA I have another matrix, y , of identical dimensions that I need to replace values with NA in positions corresponding to the locations where the elements were replaced in element z. That is, if z[3,12] was >3 and replaced with NA, I need y[3,12] to be replaced with NA too. They have the same row names if that helps. Just use is.na on the first matrix to select the values to replace in the second matrix. Example: set.seed(1) m1 <- matrix(sample(5, 25, TRUE), 5) m2 <- matrix(sample(5, 25, TRUE), 5) m1[m1

I was wondering how can I asign a conditional assignment to a php variable and use it inside other conditional, like this: $cndtnal='&& $x==4' if($y==5 $cndtnal){ print 'Hello World'; } Thanks. You should try avoiding the use of eval as much as possible, but if you want to use it, then you could do: $cndtnal='&& $x=4'; if($y==5 .eval("return '$cndtnal';") ){ echo 'Hello World'; } else { echo "this"; } 来源： https://stackoverflow.com/questions/12170527/php-variable-as-conditional-assignment