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"inconsistent use of tabs and spaces in indentation" [duplicate]
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Closed 3 years ago.
I'm using python 3.7.2 shell in linux mint 32bit.
when I run my def of factorial(as shown in code) it says that "" operator can't be apply for 'int' & 'nonetype' but i am using "" inside print function but that does no work.
even though i am not able to use return statements inside function in script mode although it works in interactive mode.
help me how can i use return statements inside function in script mode & please fix my factorial code so it works.
def factorial(n):
if n == 0:
results = print(1)
return results
else:
x = factorial(n-1)
result = print(n*x)
return result
factorial(4)
the error that i get when using this is
File "/home/Location", line 12, in factorial
result = print(n*x)
TypeError: unsupported operand type(s) for *: 'int' and 'NoneType'
when i run in interactive mode it gave this error
SyntaxError: inconsistent use of tabs and spaces in indentation
I expect the factorial evaluation 4! = 24 but it gave the error shown 2nd code in script mode, and 3rd code error in interactive mode.
print(1) will return NoneType and hence when you do a recursive call, instead of 1, you are actually sending NoneType. Separate the assignment and print as shown below and your program works:
def factorial(n):
if n == 0:
results = 1
print(results)
return results
else:
x = factorial(n-1)
result = n*x
print (result)
return result
factorial(4)
The issue is that you try to multiply a number with the result of print, which is of type NoneType, thus the error. Your factorial function should return a number, instead of printing it.
This code works:
def factorial(n):
if n==0:
return 1
else:
return n*factorial(n-1)
And only then should you print your results, for example by:
print(factorial(10))
timeoutRemaining = round(timeout - diff, 0)
TypeError: unsupported operand type(s) for -: 'str' and 'float'
# start all the threads
for i in range(totalMethods):
threads[i].start()
diff = time.time() - startTime
timeoutRemaining = round(timeout - diff, 0)
# sleep for timeout
time.sleep(timeoutRemaining)
Please help.
Looks like a typing issue. Make sure you are performing math on arithmetic types.
In other words 'startTime' (a str) is not a float.
I have an ets table which you can imagine there are two columns, "Key" and Value. Value is an integer.
When I tried:
Ans = ets:select(Table_name, MS),
Ans + 1.
where Ans equals to the expected Value.
I got a error:
** exception error: an error occurred when evaluating an arithmetic expression
Can I not do any arithmetic operation on the ets:select return value?
in the ets module spec: select(Tab, MatchSpec) -> [Match], the reurn value is a list of match. If your match specification define one single integer value as return, you will receive a list of integer. In your case, it seems that this list will always have a length of 1 element, if it must be the case, you can write:
[Ans] = ets:select(Table_name, MS),
Ans + 1.
But beware that this code will crash if the returned list is empty or have more than 1 element.
ets:select(Table_name, MS)
will return result in a List.
So instead, the following would work:
[Ans] = ets:select(Table_name, MS),
Ans + 1.
I'm noticing a strange error in my production application logs:
ActionView::Template::Error (Infinity): /path/to/page/with/problem
/myapp/shared/bundled_gems/ruby/1.9.1/gems/activesupport-3.0.20/lib/active_support/core_ext/float/rounding.rb:16:in `round'
/myapp/shared/bundled_gems/ruby/1.9.1/gems/activesupport-3.0.20/lib/active_support/core_ext/float/rounding.rb:16:in `round'
/myapp/shared/bundled_gems/ruby/1.9.1/gems/activesupport-3.0.20/lib/active_support/core_ext/float/rounding.rb:14:in `round'
/myapp/current/path/to/file/with/problem.rb:106:in `my_buggy_method'
In the code there is something like this:
def my_buggy_method
(number1 - number2).round(2)
end
I don't have any insight as to what numbers are triggering this error. How can I refactor my code to avoid this error?
Update: I managed to start up a Rails console in production and track down the values that are being used in the method above:
number1 == Infinity
number2 == 0
Update: Upon further investigation, number1 is returning Infinity because of division by zero:
number1 == 113 / 0.0
Now that I know where this Infinity is coming from, I will add a check to make sure I can never divide by zero.
The cause of this error was due to trying to round or display Infinity. I did not expect this number, so I have added extra checks to make sure that I don't create Infinity by dividing by zero.
I have many text files of this format
....
<snip>
'FOP' 0.19 1 24 1 25 7 8 /
'FOP' 0.18 1 24 1 25 9 11 /
/
TURX
560231
300244
70029
200250
645257
800191
900333
600334
770291
300335
220287
110262 /
SUBTRACT
'TURX' 'TURY'/
</snip>
......
where the portions I snipped off contain other various data in various formats. The file format is inconsistent (machine generated), the only thing one is assured of is the keyword TURX which may appear more than once. If it appears alone on one line, then the next few lines will contain numbers that I need to fetch into an array. The last number will have a space then a forward slash (/). I can then use this array in other operations afterwards.
How do I "search" or parse a file of unknown format in fortran, and how do I get a loop to fetch the rest of the data, please? I am really new to this and I HAVE to use fortran. Thanks.
Fortran 95 / 2003 have a lot of string and file handling features that make this easier.
For example, this code fragment to process a file of unknown length:
use iso_fortran_env
character (len=100) :: line
integer :: ReadCode
ReadLoop: do
read (75, '(A)', iostat=ReadCode ) line
if ( ReadCode /= 0 ) then
if ( ReadCode == iostat_end ) then
exit ReadLoop
else
write ( *, '( / "Error reading file: ", I0 )' ) ReadCode
stop
end if
end if
! code to process the line ....
end do ReadLoop
Then the "process the line" code can contain several sections depending on a logical variable "Have_TURX". If Have_TRUX is false you are "seeking" ... test whether the line contains "TURX". You could use a plain "==" if TURX is always at the start of the string, or for more generality you could use the intrinsic function "index" to test whether the string "line" contains TURX.
Once the program is in the mode Have_TRUX is true, then you use "internal I/O" to read the numeric value from the string. Since the integers have varying lengths and are left-justified, the easiest way is to use "list-directed I/O": combining these:
read (line, *) integer_variable
Then you could use the intrinsic function "index" again to test whether the string also contains a slash, in which case you change Have_TRUX to false and end reading mode.
If you need to put the numbers into an array, it might be necessary to read the file twice, or to backspace the file, because you will have to allocate the array, and you can't do that until you know the size of the array. Or you could pop the numbers into a linked list, then when you hit the slash allocate the array and fill it from the linked list. Or if there is a known maximum number of values you could use a temporary array, then transfer the numbers to an allocatable output array. This is assuming that you want the output argument of the subroutine be an allocatable array of the correct length, and the it returns one group of numbers per call:
integer, dimension (:), allocatable, intent (out) :: numbers
allocate (numbers (1: HowMany) )
P.S. There is a brief summary of the language features at http://en.wikipedia.org/wiki/Fortran_95_language_features and the gfortran manual has a summary of the intrinsic procedures, from which you can see what built in functions are available for string handling.
I'll give you a nudge in the right direction so that you can finish your project.
Some basics:
Do/While as you'll need some sort of loop
structure to loop through the file
and then over the numbers. There's
no for loop in Fortran, so use this
type.
Read
to read the strings.
To start you need something like this:
program readlines
implicit none
character (len=30) :: rdline
integer,dimension(1000) :: array
! This sets up a character array with 30 positions and an integer array with 1000
!
open(18,file='fileread.txt')
do
read(18,*) rdline
if (trim(rdline).eq.'TURX') exit !loop until the trimmed off portion matches TURX
end do
See this thread for way to turn your strings into integers.
Final edit: Looks like MSB has got most of what I just found out. The iostat argument of the read is the key to it. See this site for a sample program.
Here was my final way around it.
PROGRAM fetchnumbers
implicit none
character (len=50) ::line, numdata
logical ::is_numeric
integer ::I,iost,iost2,counter=0,number
integer, parameter :: long = selected_int_kind(10)
integer, dimension(1000)::numbers !Can the number of numbers be up to 1000?
open(20,file='inputfile.txt') !assuming file is in the same location as program
ReadLoop: do
read(20,*,iostat=iost) line !read data line by line
if (iost .LT. 0) exit !end of file reached before TURX was found
if (len_trim(line)==0) cycle ReadLoop !ignore empty lines
if (index(line, 'TURX').EQ.1) then !prepare to begin capturing
GetNumbers: do
read(20, *,iostat=iost2)numdata !read in the numbers one by one
if (.NOT.is_numeric(numdata)) exit !no more numbers to read
if (iost2 .LT. 0) exit !end of file reached while fetching numbers
read (numdata,*) number !read string value into a number
counter = counter + 1
Storeloop: do I =1,counter
if (I<counter) cycle StoreLoop
numbers(counter)=number !storing data into array
end do StoreLoop
end do GetNumbers
end if
end do ReadLoop
write(*,*) "Numbers are:"
do I=1,counter
write(*,'(I14)') numbers(I)
end do
END PROGRAM fetchnumbers
FUNCTION is_numeric(string)
IMPLICIT NONE
CHARACTER(len=*), INTENT(IN) :: string
LOGICAL :: is_numeric
REAL :: x
INTEGER :: e
is_numeric = .FALSE.
READ(string,*,IOSTAT=e) x
IF (e == 0) is_numeric = .TRUE.
END FUNCTION is_numeric