I have an input file with letters and numbers that I'd like to delimit with numbers in Fortran 90/95. The input file looks like this:
AAAA (spaces) 123BBBB (spaces) 4CCCC (spaces) 5DDDD (spaces) -6EEEE
So on and so forth. I'd like for the numbers after the spaces to be with the four letters prior to the spaces. The problem I'm running into here is that the numbers can either be one, two, three, or four digits, and can have negative signs as well. I'm not sure how to automate delimiting in Fortran to get the appropriate numbers to the correct letters.
So far, I only have written a script which essentially replicates the input file and writes it to an output file. I wanted to accomplish this first before trying delimiting as above.
ALTERNATIVELY, I can try delimiting in Python (if it's easier in Python), and call the Python delimiting script from the Fortran program.
Fortran has the SCAN and VERIFY intrinsics that let you find the location in a string of the first (or optionally last) character that is (or is not) in a specified character set. Your example is malformed as there is no number after EEEE, but I'll ignore that for now.
The way I would handle this is to keep a position value, use INDEX to locate the next blank, which tells me how many letters are there from the current position. Then I would use VERIFY with a set ' -0123456789' to identify the next non-numeric. This tells me what the next number is. I'd use a list-directed READ from that substring to read the number. Repeat until end of string.
There are undoubtedly other ways of doing this, but calling out to another language is wholly unnecessary.
Related
I got a Fortran code for K-means clustering from online.
As I am new to Fortran, I do not have an idea about the required input file format for the code as below.
How to prepare an input file according to this Fortran code?
infile1='D1_TR_all_cent63.dat'
OPEN(1,FILE=infile1,form='formatted',access='direct',
+ recl=429)
istep=nvectors/nclusters
DO i=1,nclusters
READ(1,23,rec=istep*(i-1)+1)(vec(j),j=1,42)
DO k=1,nelements
centroid(i,k)=vec(k)
END DO
END DO
23 format(42(f10.3))
It's looking for a file where each line contains 42 fields where it expects to find fixed point numbers. That's the 42(f10.3) in the format
statement. Each of those fields is 10 characters wide; there are no commas or other separator characters between them, although spaces are allowed.
For example:
123456.789 123.123 -123.123 12345.678 0.000
(and onward until there are 42 of those).
Most FORTRAN implementations will be a bit merciful on reading: You can leave off some of the after-decimal point digits, or have a space after the number (but you have to stay in the 10-character fields). But not all do, so it might be better to prepare your input with 6 digits (including sign, if needed, and allowing spaces instead) before the decimal point and three after.
I am trying to create an MDM file using HLM 7 Student version, but since I don't have access to SPSS I am trying to import my data using ASCII input. As part of this process I am required to input the data format Fortran style. Try as I might I have not been able to understand this step. Could someone familiar with Fortran (or even better HLM itself) explain to me how this works? Here is my current understanding
From the example EG3.DAT they give
(A4,1X,3F7.1)
I think
A4 signifies that the ID is 4 characters long.
1X means skip a space.
F.1 means that it should read 1 decimal places.
I am very confused about what 3F7 might mean.
EG3.DAT
2020 380.0 40.3 12.5
2040 502.0 83.1 18.6
2180 777.0 96.6 44.4
Below are examples from the help documents.
Rules for format statement
Format statement example
EG1 data format
EG2 data format
EG3 data format
One similar question is Explaining Fortran Write Format. Unfortunately it does not explicitly treat the F descriptor.
3F7.1 means 3 floating point numbers, each printed over 7 characters, each with one decimal number behind the decimal point. Leading characters are blanks.
For reading you don't need the .1 info at all, just read a floating point number from those 7 characters.
You guessed the meaning of A4 (string of four characters) and 1X (one blank) correctly.
In Fortran, so-called data edit descriptors (which format the input or output of data) may have repeat specifications.
In the format (A4,1X,3F7.1) the data edit descriptors are A4 and F7.1. Only F7.1 has a repeat specification (the number before the F). This simply means that the format is as though the descriptor appeared repeated: like F7.1, F7.1, F7.1. With a repeat specification of 1, or not given, there is just the single appearance.
The format of the question, then, is like
(A4,1X,F7.1,F7.1,F7.1)
This format is one that is covered by the rules provided in one of the images of the question. In particular, the aspect of repeat specification is given in rule 2 with the corresponding example of rule 3.
Further, in Fortran proper, a repeat count specifier may also be * as special case: that's like an exceptionally large repeat count. *(F7.1) would be like F7.1, F7.1, F7.1, .... I see no indication that this is supported by HLM but if this is needed a very large repeat count may be given instead.
In 1X the 1 isn't a repeat specification but an integral, and necessary, part of the position edit descriptor.
Procedure for making MDM file from excel for HLM:
-Make sure ALL the characters in ALL the columns line up
Select a column, then right click and select Format Cells
Then click on 'Custom' and go to the 'Type' box and enter the number
of 0s you need to line everything up
-Remove all the tabs from the document and replace them with spaces.
Open the document in word and use find and replace
-To save the document as .dat
First save it as .txt
Then open it in Notepad and save it as .dat
To enter the data format (FORTRAN-Style)
The program wants to read the data file space by space, so you have to specify it perfectly so that it reads the whole set properly.
If something is off, even by a single space, then your descriptive stats will be wonky compared to if you check them in another program.
Enclose the code with brackets ()
Divide the entries with commas ,
-Need ID column for all levels
ID column needs to be sorted so that it is in order from smallest to
largest
Use A# with # being the number of characters in the ID
Use an X1 to
move from the ID to the next column
-Need to say how many characters are needed in each column
Use F
After F is the number of characters needed for that column -Use F# (#= number)
There need to be enough character spaces to provide one 'gap' space
between each column
There need to be enough to character spaces to allow for the decimal
As part of the F you need to specify the number of decimal places
You do this by adding a decimal point after the F number and then a
number to represent the spaces you need -F#.#
You can use a number in front of the F so as to 'repeat' it. Not
necessary though. -#F#.#
All in all, it should look something like this:
(A4,X1,F4.0,F5.1)
Helpful links:
https://books.google.de/books?id=VdmVtz6Wtc0C&pg=PA78&lpg=PA78&dq=data+format+fortran+style+hlm&source=bl&ots=kURJ6USN5e&sig=fdtsmTGSKFxn04wkxvRc2Vw1l5Q&hl=en&sa=X&ved=0ahUKEwi_yPurjYrYAhWIJuwKHa0uCuAQ6AEIPzAC#v=onepage&q&f=false
http://www.ssicentral.com/hlm/help6/error/Problems_creating_MDM_files.pdf
http://www.ssicentral.com/hlm/help7/faq/FAQ_Format_specifications_for_ASCII_data.pdf
Hy everybody, I've found some problems in reading unformatted character strings in a simple file. When the first / is found, everything is missed after it.
This is the example of the text I would like to read: after the first 18 character blocks that are fixed (from #Mod to Flow[kW]), there is a list of chemical species' names, that are variables (in this case 5) within the program I'm writing.
#Mod ID Mod Name Type C. #Coll MF[kg/s] Pres.[Pa] Pres.[bar] Temp.[K] Temp.[C] Ent[kJ/kg K] Power[kW] RPM[rad/s] Heat Flow[kW] METHANE ETHANE PROPANE NITROGEN H2O
I would like to skip, after some formal checks, the first 18 blocks, then read the chemical species. To do the former, I created a character array with dimension of 18, each with a length of 20.
character(20), dimension(18) :: chapp
Then I would like to associate the 18 blocks to the character array
read(1,*) (chapp(i),i=1,18)
...but this is the result: from chapp(1) to chapp(7) are saved the right first 7 strings, but this is chapp(8)
chapp(8) = 'MF[kg '
and from here on, everything is leaved blank!
How could I overcome this reading problem?
The problem is due to your using list-directed input (the * as the format). List-directed input is useful for quick and dirty input, but it has its limitations and quirks.
You stumbled across a quirk: A slash (/) in the input terminates assignment of values to the input list for the READ statement. This is exactly the behavior that you described above.
This is not choice of the compiler writer, but is mandated by all relevant Fortran standards.
The solution is to use formatted input. There are several options for this:
If you know that your labels will always be in the same columns, you can use a format string like '(1X,A4,2X,A2,1X,A3,2X)' (this is not complete) to read in the individual labels. This is error-prone, and is also bad if the program that writes out the data changes format for some reason or other, or if the labes are edited by hand.
If you can control the program that writes the label, you can use tab characters to separate the individual labels (and also, later, the labels). Read in the whole line, split it into tab-separated substrings using INDEX and read in the individual fields using an (A) format. Don't use list-directed format, or you will get hit by the / quirk mentioned above. This has the advantage that your labels can also include spaces, and that the data can be imported from/to Excel rather easily. This is what I usually do in such cases.
Otherwise, you can read in the whole line and split on multiple spaces. A bit more complicated than splitting on single tab characters, but it may be the best option if you cannot control the data source. You cannot have labels containing spaces then.
It would be easy to make everything in the file lowercase and find it, but I want to find the string with the original capitalization so I could put it to a pointer and print it later. For example
FIND_WORD ransom.
File Word found. Line added
DISPLAY
rAnSoM nOtE. yOu HaVe TiLl nOon.
Go through the file line by line. For each line, go through the string from beginning to end.
For each starting point in the line, do a case-insensitive compare of the subsequent characters in the string to the characters in the word you're trying to find. If they all match, output that entire line as originally read.
In other words, don't convert anything to lower case. Instead, do a case-insensitive compare.
I am writing some simple output in fortran, but I want whitespace delimiters. If use the following statement, however:
format(A20,ES18.8,A12,ES18.8)
I get output like this:
p001t0000 3.49141273E+01obsgp_oden 1.00000000E+00
I would prefer this:
p001t0000 3.49141273E+01 obsgp_oden 1.00000000E+00
I tried using negative values for width (like in Python) but no dice. So, is there a way to left-justify the numbers?
Many thanks in advance!
There's not a particularly beautiful way. However, using an internal WRITE statement to convert the number to a text string (formerly done with an ENCODE statement), and then manipulating the text may do what you need.
Quoting http://rsusu1.rnd.runnet.ru/develop/fortran/prof77/node168.html
An internal file WRITE is typically
used to convert a numerical value to a
character string by using a suitable
format specification, for example:
CHARACTER*8 CVAL
RVALUE = 98.6
WRITE(CVAL, '(SP, F7.2)') RVALUE
The WRITE statement will fill the
character variable CVAL with the
characters ' +98.60 ' (note that there
is one blank at each end of the
number, the first because the number
is right-justified in the field of 7
characters, the second because the
record is padded out to the declared
length of 8 characters).
Once a number has been turned into a
character-string it can be processed
further in the various ways described
in section 7. This makes it possible,
for example, to write numbers
left-justified in a field, ...
This is easier with Fortran 95, but still not trivial. Write the number or other item to a string with a write statement (as in the first answer). Then use the Fortran 95 intrinsic "ADJUSTL" to left adjust the non-blank characters of the string.
And really un-elegant is my method (I program like a cave woman), after writing the simple Fortran write format (which is not LJ), I use a combination of Excel (csv) and ultraedit to remove the spaces effectively getting the desired LJ followed directly by commas (which I need for my specific import format to another software). BF
If what you really want is whitespace between output fields rather than left-justified numbers to leave whitespace you could simply use the X edit descriptor. For example
format(A20,4X,ES18.8,4X,A12,4X,ES18.8)
will insert 4 spaces between each field and the next. Note that the standard requires 1X for one space, some of the current compilers accept the non-standard X too.
!for left-justified float with 1 decimal.. the number to the right of the decimal is how many decimals are required. Write rounds to the desired decimal space automatically, rather than truncating.
write(*, ['(f0.1)']) RValue !or
write(*, '(f0.1)') RValue
!for left-justified integers..
write(*, ['(i0)']) intValue !or
write(*, '(i0)') RValue
*after feedback from Vladimir, retesting proved the command works with or without the array brackets