5 replies to this topic

[UP844]

So I want to make my own calculator program. I don't to use someone elses because this is the idea I've had for a program in such a long time. But anyway I'm using this code:

local args = {...}
local first = tonumber (args[1]) or 1
local second = tonumber (args[2]) or 1

I want to know if I can add a code in between line 2 and 3 that says:

local sign = tonumber (args[3]) or (something)

And then

print (first (how to run the sign so I can choose whatever sign I want) second)

So basically it takes first and second, and does whatever to them that the sign thing says. If there's not really a way to make this way work please tell me a way that will.

[Shnupbups]

local args = {...}
local first = tonumber(args[1]) or 1
local sign = args[2] or "+"
local second = tonumber(args[3]) or 1
if sign == "+" then
print(first+second)
elseif sign == "-" then
print(first-second)
elseif sign == "*" or sign == "x" then
print(first*second)
elseif sign == "/" then
print(first/second)
end

Then type

<ProgramName> <number> <+,-,x,*,or /> <number>

to execute. If you don't know how this code works, look on the wiki and the Lua Reference Manual for help.

[UP844]

Shnupbups100, on 23 February 2013 - 05:03 PM, said:

local args = {...}
local first = tonumber(args[1]) or 1
local sign = args[2] or "+"
local second = tonumber(args[3]) or 1
if sign == "+" then
print(first+second)
elseif sign == "-" then
print(first-second)
elseif sign == "*" or sign == "x" then
print(first*second)
elseif sign == "/" then
print(first/second)
end

Then type

<ProgramName> <number> <+,-,x,*,or /> <number>

to execute. If you don't know how this code works, look on the wiki and the Lua Reference Manual for help.

Thanks!!!! And I'm really bad at programming so it'll take me a while before I can actually write a decent program without having to ask someone for help with it. But yeah thanks!!!!

[UP844]

Shnupbups100, on 23 February 2013 - 05:03 PM, said:

local args = {...}
local first = tonumber(args[1]) or 1
local sign = args[2] or "+"
local second = tonumber(args[3]) or 1
if sign == "+" then
print(first+second)
elseif sign == "-" then
print(first-second)
elseif sign == "*" or sign == "x" then
print(first*second)
elseif sign == "/" then
print(first/second)
end

Then type

<ProgramName> <number> <+,-,x,*,or /> <number>

to execute. If you don't know how this code works, look on the wiki and the Lua Reference Manual for help.

And also, I want to make some way so if first, sign, and second are just left blank it would do something like print

Usage: <programname> <first#> <operation> <second#>

[NDFJay]

UP844, on 23 February 2013 - 05:48 PM, said:

And also, I want to make some way so if first, sign, and second are just left blank it would do something like print

Usage: <programname> <first#> <operation> <second#>

if args < 3 then
error("Usage: <programname> <first#> <operation> <second#>")
end

[Shnupbups]

NDFJay, on 23 February 2013 - 06:42 PM, said:

if #args < 3 then
error("Usage: <programname> <first#> <operation> <second#>")
end

Fixed