python - Can't get simple if..elif test to work with testing for a number -


my assignment is:

you have been asked write program give name of shape depending on number of sides. user can enter numbers between 3 , 8, if enter other number program should tell them enter number between 3 , 8.

and here's python answer:

#sides , shapes sides = int(input("how many sides on shape there? ")) if sides ==3:     print ("your shape triangle") if sides ==4:     print ("your shape square") if sides ==5:     print ("your shape pentagon") if sides ==6:     print ("your shape hexagon") if sides ==7:     print ("your shape heptagon") if sides ==8:     print ("your shape octagon") elif sides != range(3,9):     print ("you should enter number between 3 , 8")

after elif statement somehow need loop if person inputs other 3-8 keep asking them enter number 3 8.

the elif statement not work reason , outputs answer in f5:

how many sides on shape there? 6 shape hexagon should enter number between 3 , 8

range() produces object of different type; integer != range() always going true.

either test if integer outside range < or <= , chaining:

elif not (3 <= sides < 9):     print ("you should enter number between 3 , 8")

or use not in see if number outside range:

elif sides not in range(3, 9):     print ("you should enter number between 3 , 8")

or use elif on all tests first, , else last branch; it'll picked if if..elif tests did not match:

if sides ==3:     print ("your shape triangle") elif sides ==4:     print ("your shape square") elif sides ==5:     print ("your shape pentagon") elif sides ==6:     print ("your shape hexagon") elif sides ==7:     print ("your shape heptagon") elif sides ==8:     print ("your shape octagon") else:     print ("you should enter number between 3 , 8")

note there one if now; logically, elif , else parts belong 1 if statement. other if forms separate, new set of choices, , sides != range(3, 9) expression true, meaning elif test true time if slides == 8 not true.

you can simplify code using dictionary. lets associate key value; make numbers keys, , can test if sides in dictionary, or return default value if not:

shape_msg = "your shape " result = {     3: shape_msg + "triangle",     4: shape_msg + "square",     5: shape_msg + "pentagon",     6: shape_msg + "hexagon",     7: shape_msg + "heptagon",     8: shape_msg + "octagon", }  sides = int(input("how many sides on shape there? ")) result = results.get(sides, "you should enter number between 3 , 8") print(result)

here, dict.get() method returns value given key, or default value if key not present.

if need continue loop, test presence of key , branch based on that:

while true:     sides = int(input("how many sides on shape there? "))     if sides in result:         print(sides[result])         break  # done, exit loop      print("you should enter number between 3 , 8")

for further tips on how ask user input , handle wrong input, see asking user input until give valid response.


Comments

Post a Comment

Popular posts from this blog

authentication - Mongodb revoke acccess to connect test database -

i have ec2 instance mongodb 3.2.0 installed. have user admin access. can connect user , perform operation remotely. 1 can connect database test remote if knows ip mongo 11.11.11.11. although not able make operations, want restrict access user credentials can connect server. first need create users , grant roles users, example: use admin db.createuser( { user: "myuseradmin", pwd: "abc123", roles: [ { role: "useradminanydatabase", db: "admin" } ] } ) then need start server --auth parameter mongod --auth more information here
Read more

r - Update two sets of radiobuttons reactively - shiny -

i have read ( how make choices in radiobuttons reactive in shiny? ) shows me how update radiobutton s in reactive way. however, when try , update 2 sets of buttons same data, 1 set renders. example: server: # create example data wafer <- rep(c(1:3), each=3) length <- c(1,1,2,1,1,1,3,5,1) width <- c(3,1,6,1,1,1,1,1,6) dd <- data.frame(wafer, length, width) shinyserver(function(input, output, session){ # create reactive dataframe store data values <- reactivevalues() values$df <- data.frame() # lengths , widths of wafer user input <- eventreactive(input$do, { subset(dd, wafer %in% input$wafer, select = length:width) }) # update reactive data frame lengths , widths have been selected user input observe({ if(!is.null(a())) { values$df <- rbind(isolate(values$df), a()) } }) output$wl <- renderdatatable({ a() }) # update radio buttons unique length , widths stored in values$df # ever "observe" put first in co...
Read more

ios - Realm over CoreData should I use NSFetchedResultController or a Dictionary? -

i'm working on app using core data , nsfetchedresultcontroller many reasons switch use realm. saw there "realm version" of nsfetchedresultcontroller on github wouldn't compatible current code using core data. the view controller displaying list of people same school, address book. list sublist of people studied in same city. so thinking make 1 unique request database retrieve list of people , filter locally list within 1 dictionary per school [string: anyobject] string section name within tableview , anyobject array of people. first solution, make nsfetchedresultcontroller each school predicate filtering location. delete actions etc.. handled delegates -> not compatible realm create dictionaries , update them each actions... -> works realm it's annoying code. any better solution? edit: i need clarify request: i'd write class inherit uitableviewcontroller. this class has list of people sorted in alphabetical order the tableview has ...
Read more