I am programming an instrument that uses Lua with extensions for accessing the instrument controls and displays.
The instrument has a command to read the analyzer plotted points for frequency and amplitude:
:analyzer:trace:frequency?
and
:analyzer:trace:amplitude?
Whenever either of the above is executed, 768 values are returned (frequency or amplitude). This is an embedded test system running Lua for user apps - I can't change the command.
I tried to use table.pack() to put these returned values into a table, but the syntax of the command with the ":" causes an error.
Code I tried --
freq = {};
freq = table.pack(:analyzer:trace:frequency?);
Error message is -- tests.lua:2428: unexpected symbol near ':'
Whenever the :analyzer:trace:frequency? is run stand alone (from PuTTY) or as a line in the Lua code, there is no error.
PuTTY receives 768 frequency values, each separated by a comma.
Looking for ways to direct the return into an array/table or to wrap the command so that it will execute similarly as above.
Thanks
I'm attempting to write a script in LUA for the Minecraft mod ComputerCraft. It's supposed to send a turtle down, mine a hole, and place ladders before returning to the surface. I'm trying to make an error display when the turtle doesn't have enough ladders, but I'm receiving an error that prevents it from running. "mineDown :18: attempt to compare string with number expected, got string."
-- This gets the user to tell the turtle how far to dig down
print('How far down should I go?')
distDown = io.read()
distMoved = 0
ladders = turtle.getItemCount(13)
-- Check if the number of ladders is less than the distance needed to move. If so, returns error.
turtle.select(13)
if ladders < distDown then
error('Not enough ladders!')
end
The error means that ladders is number and distDown is a string. You need to convert them to the same type. For example to convert ladders to a string use tostring or distDown to a number use tonumber:
if ladders < tonumber(distDown) then
I am not able to understand what is the logic behind these lines:
COMPUTE temp = RESULT - 1.843E19.
IF temp IS LESS THAN 1.0E16 THEN
Data definition:
000330 01 VAR1 COMP-1 VALUE 3.4E38. // 3.4 x 10 ^ 38
Here are those lines in context (the sub-program returns a square root):
MOVE VAR1 TO PARM1.
CALL "SQUAREROOT_ROUTINE" USING
BY REFERENCE PARM1,
BY REFERENCE RESULT.
COMPUTE temp = RESULT - 1.843E19.
IF temp IS LESS THAN 1.0E16 THEN
DISPLAY "OK"
ELSE
DISPLAY "False"
END-IF.
These lines are just trying to test if the result returned by the SQUAREROOT_ROUTINE is correct. Since the program is using float-values and rather large numbers this might look a bit complicated. Let's just do the math:
You start with 3.4E38, the squareroot is 1.84390889...E19.
By subtracting 1.843E19 (i.e. the approximate result) and comparing the difference against 1.0E16 the program is testing whether the result is between 1.843E19 and 1.843E19+1.0E16 = 1.844E19.
Not that this test would not catch an error if the result from SQUAREROOT_ROUTINE was too low instead of too high. To catch both types of wrong results you should compare the absolute value of the difference against the tolerance.
You might ask "Why make things so complicated"? The thing is that float-values usually are not exact and depending on the used precision you will get sightly different results due to rounding-errors.
well the logic itself is very straight forward, you are subtracting 1.843*(10^19) from the result you get from the SQUAREROOT_ROUTINE and putting that value in the variable called temp and then If the value of temp is less than 1.0*(10^16) you are going to print a line out to the SYSOUT that says "OK", otherwise you are going to print out "False" (if the value was equal to or greater than).
If you mean the logic as to why this code exists, you will need to talk to the author of the code, but it looks like a debugging display that was left in the program.
For my program delphi-code-coverage-wizard, I need to verify that a (detailed) mapping file .map matches a Delphi application .exe
Of course, this verification should be realized with Delphi.
Is there a way to check it ? Maybe by verifying some information from the EXE ?
I think a quite simple heuristic would be to check that the various sections in the PE file start and finish at the same place:
For example, here's the top of a map file.
Start Length Name Class
0001:00401000 000A4938H .text CODE
0002:004A6000 00000C9CH .itext ICODE
0003:004A7000 000022B8H .data DATA
0004:004AA000 000052ACH .bss BSS
0005:00000000 0000003CH .tls TLS
I also looked at what dumpbin /headers had to say about these sections:
SECTION HEADER #1
.text name
A4938 virtual size
1000 virtual address (00401000 to 004A5937)
A4A00 size of raw data
400 file pointer to raw data (00000400 to 000A4DFF)
0 file pointer to relocation table
0 file pointer to line numbers
0 number of relocations
0 number of line numbers
60000020 flags
Code
Execute Read
SECTION HEADER #2
.itext name
C9C virtual size
A6000 virtual address (004A6000 to 004A6C9B)
E00 size of raw data
A4E00 file pointer to raw data (000A4E00 to 000A5BFF)
0 file pointer to relocation table
0 file pointer to line numbers
0 number of relocations
0 number of line numbers
60000020 flags
Code
Execute Read
...truncated
Look at the .text section. According to dumpbin it starts at 00401000 and finishes at 004A5937 which is a length of 000A4938, exactly as in the .map file. Naturally you'd read the PE file directly rather than running dumpbin, but this illustrates the point.
I'd expect a vanishingly small number of false positives with this approach.
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