Question

Please, is anyone here familiar with Python Version 3.4.1?
@ Anyone at all who can help me, please help, my assignment is due in 4 hours 30 minutes and ive been stuck witht he same problem for 4 days already

Answer 1

My code so far
```
print('1. Argentine Peso')
print('2. Brazilian Real')
print('3. British Pound')
print('4. European Euro')
print('5. Indian Rupee')
print('6. Japanese Yen')
print('7. Russian Ruble')
print('8. Other \n')

usd = 0
print('-----------------------------------------------------------')
usd = eval(input('Enter amount to convert (=< 0 to exit): '))

peso = usd * 8.48
real = usd * 2.46
pound = usd * 0.62
euro = usd * 0.79
rupee = usd * 61.59
yen = usd * 109.49
ruble = usd * 39.45

num = 0
num = eval(input('Enter Selection: '))
while num > 0:
num = num + 1
if num == 1:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(peso,2)) + ' Argentine Pesos.')
elif num == 2:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(real,2)) + ' Brazilian Real.')
elif num == 3:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(pound,2)) + ' British Pound.')
elif num == 4:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(euro,2)) + ' European Euro.')
elif num == 5:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(rupee,2)) + ' Indian Rupee.')
elif num == 6:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(yen,2)) + ' Japanese Yen.')
elif num == 7:
print('' + str(usd) + ' US Dollars converts to: ' + str(ruble) + ' Russian Ruble.')
elif num == 8:
currency = input('Enter current to convert to: ')
amount = eval(input('Enter the conversion factor for ' + currency + ': '))
random = usd * amount
print('' + str(usd) + ' US Dollars converts to: ' + str(random) + ' ' + currency + '.')
else:
print('-----------------------------------------------------------') #mark of starting over
eval(input('Enter amount to convert (=<0 to exit): '))
num = eval(input('Enter selection: '))
```

Answer 2

It works pretty well so far but right now it after you select a number 1-8, it adds 1 to your selection and prnts all after that one.

Example:
Selection is 4, the program runs selection #s 5,6,7,8 and restarts the program

Answer 3

@e.mccormick hey so i know ive already asked for you to help with this exact problem but i still cant figure out what the problem is. any chance you would be willing to help again :\

Answer 4

Well, you are adding to the num... =/

Answer 5

someone told me that my problem has to do with using
```
num=num+1
```
i tried many things but idk, i need it because its the only thing i could find to do to fix the infinite loop problem i had before

Answer 6

Well, are you trying to offer the person a chance to convert again, or to a different ammount of money?

Answer 7

yes im trying to allow the user to choose one conversion after entering an amount for usd, then after that one conversion it should ask for a new value for usd and allow them to pick a new conversion option.

Answer 8

Then put the user input inside the loop and also tell them to put in 0 to exit.

Answer 9

This is my actualy assignment instruction paper if you wanna look quick

Answer 10

Your loop is also evaluation on the wrong value.

Answer 11

what do you mean by that?

Answer 12

'while num > 0:'
Instructions:
Write a program to continually ask the user for a US dollar amount to be converted to a monetary value in some other currency. Terminate the program when the user enters zero(0) or a negative value.

num is not the monetary value.

Answer 13

usd is the monetary value?

Answer 14

Yes. USD is the monitary value

Also, think about this:
```
flag = true
while flag:
if input <= 0:
flag = false
other stuff
```
That is one possible solution. Or doing if and a break/continue and testing on usd > 0.

Answer 15

A do-while loop is another possibility because that does stuff at least once.

Answer 16

yeah another person suggested the do-while loop but i dont believe we learned about those just yet

Answer 17

as far as loops go, we learned while and for loops

Answer 18

but only the basic while loop

Answer 19

They have it end right after the curency is set to 0, so you need to use an if-break construct.

Answer 20

if i put the piece where user inputs usd value and makes a selection, inside the while loop, all it prints are #1-8 selections and program ends

Answer 21

You just need to make it true before they input the amount. You made it false.

Answer 22

Also, watch out for where your calculations happen.

Answer 23

```
peso = usd * 8.48
real = usd * 2.46
pound = usd * 0.62
euro = usd * 0.79
rupee = usd * 61.59
yen = usd * 109.49
ruble = usd * 39.45
```
should this be inside the while?

Answer 24

Yep. You need to recalculate after a new value it taken in and before the print of the new output.

Answer 25

alright so i think its working, is my else statement at the bottom just totally pointless?

Answer 26

No. It is incorrect, but not pointless. You would use an else there for an error message if they entered an invalid type of currency.

Answer 27

ooooh so its correct but i should make it print something else.

Answer 28

i think ill just remove it, an error message isnt required for this and i dont need to complicate things at this point lol

Answer 29

It is good to have an else as a catch all. No need to have any input. Just output for "What where you thinking!"

Answer 30

oh so its that easy, alright

Answer 31

See any problems?
```
print('1. Argentine Peso')
print('2. Brazilian Real')
print('3. British Pound')
print('4. European Euro')
print('5. Indian Rupee')
print('6. Japanese Yen')
print('7. Russian Ruble')
print('8. Other \n')

usd = 0
usd = eval(input('Enter amount to convert (=< 0 to exit): '))


while usd > 0:
peso = usd * 8.48
real = usd * 2.46
pound = usd * 0.62
euro = usd * 0.79
rupee = usd * 61.59
yen = usd * 109.49
ruble = usd * 39.45

num = 0
num = eval(input('Enter Selection: '))

if num == 1:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(peso,2)) + ' Argentine Pesos.')
elif num == 2:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(real,2)) + ' Brazilian Real.')
elif num == 3:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(pound,2)) + ' British Pound.')
elif num == 4:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(euro,2)) + ' European Euro.')
elif num == 5:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(rupee,2)) + ' Indian Rupee.')
elif num == 6:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(yen,2)) + ' Japanese Yen.')
elif num == 7:
print('' + str(usd) + ' US Dollars converts to: ' + str(ruble) + ' Russian Ruble.')
elif num == 8:
currency = input('Enter current to convert to: ')
amount = eval(input('Enter the conversion factor for ' + currency + ': '))
random = usd * amount
print('' + str(usd) + ' US Dollars converts to: ' + str(random) + ' ' + currency + '.')
else:
print('What were you thinking!')

```

Answer 32

ive tested each selection and seems to work

Answer 33

Well, might want a nice one like, "That is not a valid currency selection" but it works. Try it for like 9 or 42. See, that is where the else is handy.

Answer 34

Calculate after getting the new ... ummm... you still do not have it looping validly.

Answer 35

Try and get it to do the same output as in the examples.

Answer 36

alright

Answer 37

i tried to put the usd part inside the loop and it gives me an error or it just prints out the option list

Answer 38

Just as a psudocode example:
```
a = 1
while a > 0
input a
if a <= 0
exit loop
input b
print a + b
```

Because I set a to a true value, I got into the loop fine. I never actually use this value because I instantly replace it with user input. Then to make sure I have a catch to kill things, I do an if right after I get a.

Answer 39

so 'a' is my 'usd' correct?

Answer 40

sorry ik we already went over this part, just clarrifying

Answer 41

```
print('1. Argentine Peso')
print('2. Brazilian Real')
print('3. British Pound')
print('4. European Euro')
print('5. Indian Rupee')
print('6. Japanese Yen')
print('7. Russian Ruble')
print('8. Other \n')

usd = 1


while usd > 0:
usd = eval(input('Enter amount to convert (less than 0 to exit): '))

if usd <= 0: #used to exit if a negative number or 0 is entered.
exit

peso = usd * 8.48
real = usd * 2.46
pound = usd * 0.62
euro = usd * 0.79
rupee = usd * 61.59
yen = usd * 109.49
ruble = usd * 39.45

num = 0
num = eval(input('Enter Selection: '))

if num == 1:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(peso,2)) + ' Argentine Pesos.\n')
elif num == 2:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(real,2)) + ' Brazilian Real.\n')
elif num == 3:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(pound,2)) + ' British Pound.\n')
elif num == 4:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(euro,2)) + ' European Euro.\n')
elif num == 5:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(rupee,2)) + ' Indian Rupee.\n')
elif num == 6:
print('' + str(usd) + ' US Dollars converts to: ' + str(round(yen,2)) + ' Japanese Yen.\n')
elif num == 7:
print('' + str(usd) + ' US Dollars converts to: ' + str(ruble) + ' Russian Ruble.\n')
elif num == 8:
currency = input('Enter current to convert to: ')
amount = eval(input('Enter the conversion factor for ' + currency + ': '))
random = usd * amount
print('' + str(usd) + ' US Dollars converts to: ' + str(random) + ' ' + currency + '.\n')
else:
print('Invalid input! Please try again.\n')

```
idk why it all turned red but i think this is what your meaning by your example

Answer 42

In your case, yes. See how that keeps it from falling out of the loop?

Answer 43

i never knew we had an 'exit' idk what its called, a function or something?

Answer 44

Well, exit is not how to stop a loop. Did your book/class talk about how to skip or exit loops?

Answer 45

no we never really went over that

Answer 46

oh nvm that doesnt even make it exit, forgot to test it.

Answer 47

ill have to read into that part

Answer 48

http://www.tutorialspoint.com/python/python_loop_control.htm

Answer 49

ahh so 'break' makes it exit, see we had that in c++ i hadnt thought to try that on here. i took a c++ class a few years back in high school.

Answer 50

hm it exits for zero but not a negative number

Answer 51

Odd...

Answer 52

when i put a negative number it refers to the else and says invalid input and restarts

Answer 53

Did you do == 0 or <= 0?

Did you put the negative as the currency type or as the money?

Answer 54

<= 0

Answer 55

the currency type

Answer 56

lol alright i see where your going

Answer 57

the exit is if the usd = 0 or negative, so i have to do for the money not type

Answer 58

So, was it when you tested it you put it in the wrong place? =P Thought that might have been it.

Answer 59

haha yep

Answer 60

alright if you dont mind ive got one more question

Answer 61

its a quick one im sure
```
print('' + str(usd) + ' US Dollars converts to: ' + str(round(peso,2)) + ' Argentine Pesos.\n')
```
is there a better way to round to the 100th place (2 decimal place : 0.00) because this method doesnt work quite every time ive noticed

Answer 62

hm maybe it does now, i noticed earlier it wasnt round it to two decimal places when the answer was something like 6.00 it would just put 6.0

Answer 63

String format. Number format... hmm... that is a Java concept. The round might have an extra option.

Answer 64

hm alright

Answer 65

i may just turn it in like this haha, i think ive put more than what was expected to be required into this assignment lol

Answer 66

http://stackoverflow.com/questions/1995615/how-can-i-format-a-decimal-to-always-show-2-decimal-places

Answer 67

Looks like they have string format too. Thought so.

Answer 68

yeah i see it too

Answer 69

thanks that should help

Answer 70

Ah, a cleaner example then the entire format docs:
http://stackoverflow.com/questions/2389846/python-decimals-format

Answer 71

Oooh. And really good examples:
http://mkaz.com/2012/10/10/python-string-format/

Answer 72

oh wow that last one is fantastic! thank you! bookmarking that one

Answer 73

youve got no idea how much i appreciate your help over the past few days :D

Answer 74

Well, that is the hope of the site. Give you someone to talk to that knows a bit more than you do so you can get a few nudges in the right direction.

Answer 75

yep :D i hope ill be able to help some more people the way you do for me soon.
really appreciate it, now i havent slept in about 28hrs so im going sleep haha. night.

have a wonderful day/night!

thanks again!