jblood94 questions

jblood94 answers

• Sum elements with conditions on indices
• Use excel to generate table assignments for each person
• Efficiently find the number of different classmates from course-level data
• WorksheetFunction array size limit
• Speeding up simulations
• Vectorize an sapply function
• Find every combination meeting constraints
• Filtering the Results of Expand.Grid
• Compute N random permutations of a vector of 36 elements
• How can this R data.table join+group+summarise, operation be made a lot faster?