diff --git a/src/components/Fortran/Fortran_Hello_World.vue b/src/components/Fortran/Fortran_Hello_World.vue index 4a8fa4b..f4160fc 100644 --- a/src/components/Fortran/Fortran_Hello_World.vue +++ b/src/components/Fortran/Fortran_Hello_World.vue @@ -6,16 +6,19 @@
A Hello World program is always a great step into a new programming language. It gives a simple oversight into + the build process of said language. And with a simple project come a simple intro (mostly). But fret not, Fortran + can be simple or complex, depending on the size of the project.
-
+
+
program hello
implicit none
print *, 'Hello world!'
end program hello
-
+
+
In the good ol' days (before FORTRAN 77), when printing to console, you would write write(*,*)
,
but with the release of FORTRAN 77, that became redundant, as you could use the newest keyword: print
.
@@ -26,20 +29,21 @@ end program hello
as it conveys the meaning of the code better. Plus we don't need the full functionality of write(*,*)
in this example.
-
-
+
+
$ gfortran -o hello main.f90
$ ./hello
Hello world!
-
+
+
Now, hear me out, why not spice up the program a little bit more? What if we want to read user input? Well, fret
not my friend, because I have just the solution for you then. All we gotta do is to read from the terminal, and
then print out the value.
-
-
+
+
program hello
implicit none
@@ -54,8 +58,9 @@ program hello
print *, trim(usertxt)
end program hello
-
+
+
So what we're seeing here, is that we have created two variables: usertxt
and ios
.
usertxt
is the input we're reading from the terminal. Although since Fortran 90 doesn't
@@ -81,14 +86,14 @@ end program hello
make a character array longer than the actual text, it will be filled with whitespace after the text. So now the output
looks like this:
-
-
+
+
$ gfortran -o hello main.f90
$ ./hello
Input text here:
Hello world :D
Hello world :D
-
+
\ No newline at end of file
diff --git a/src/components/Fortran/Fortran_Set_Up.vue b/src/components/Fortran/Fortran_Set_Up.vue
index 87eb979..b206a3e 100644
--- a/src/components/Fortran/Fortran_Set_Up.vue
+++ b/src/components/Fortran/Fortran_Set_Up.vue
@@ -33,12 +33,12 @@
For Fedora.
- $ sudo dnf install gcc-gfortran
+ $ sudo dnf install gcc-gfortran
For ubuntu.
- $ sudo apt install gfortran
+ $ sudo apt install gfortran
@@ -49,12 +49,13 @@
When creating a Fortran project, or any project in general, you want a structure. There is a lot of different
- layouts for the structure, but equal amongst them, is the src
folder. That's where we keep all of out
- source code. Like *.f90, *.f95
files.
+ layouts for the structure, but equal amongst them, is the src
folder. That's where we keep all of out
+ source code. Like *.f90, *.f95
files.
- But other than that, most projects include a Makefile
file, a library
, test
- and bin
folder. Your layout doesn't need to look like this specifically, nor does it have to contain
+
But other than that, most projects include a Makefile
file, a
+ library
, test
+ and bin
folder. Your layout doesn't need to look like this specifically, nor does it have to contain
the same folders. Each project is different, and so are the requirements. But this layout is simple, and great
for medium to large projects.
@@ -64,8 +65,8 @@
and we will let you know, when or how we set up the project.
-
-
+
+
project/
├── src/ # Source files (.f90, .f95, etc.)
│ ├── modules/ # Module definitions
@@ -75,19 +76,127 @@ project/
├── bin/ # Executable binaries
├── tests/ # Test cases
└── Makefile # Build script
-
+
Notes:
- - >
src
(This is where we keep all of out source code).
- - >
modules
(This is where we keep our classes. Or in Fortran-speak, modules).
- - >
include
(This is where we keep our interfaces, that out modules will inherit from, if we're using Fortran 90 or above).
- - >
bin
(This is where the compiled program should end up in).
+ - >
src
(This is where we keep all of out source code).
+ - >
modules
(This is where we keep our classes. Or in Fortran-speak, modules).
+ - >
include
(This is where we keep our interfaces, that out modules will inherit from, if we're using Fortran 90 or above).
+ - >
bin
(This is where the compiled program should end up in).
- Makefiles are very useful, and becomes increasingly useful, the bigger the project gets.
+ Compiling
+
+ Makefiles are very useful, and becomes increasingly useful, the bigger the project gets. A makefile simplifies the
+ compilation process, as all of the compile flags can be gathered inside a single file. It makes it possible to
+ dynamically change the compilation depending on the system architecture or config. It also removes the need to
+ manually compile and link your objects together, every time you make a change.
+
+
+ And with a bigger project, comes a big count of source files. That's where a makefile helps a lot, as it handles
+ and tracks all changes to each file, ensuring that it's only the changed files that gets re-compiled.
+
+
+ So let's see a makefile in action. Below code is a simple Hello World application, that we will use a makefile to
+ compile. Although it's worth noting, that a program this small, a makefile is wildly redundant. But it does show
+ how it's set up in a simple environment.
+
+
+ hello.f90
+
+
+program hello
+ implicit none
+ print *, 'Hello, World!'
+end program hello
+
+
+
+
+ The makefile, in the eyes of a modern programmer (C#, Python, JS, Etc) might look rather repulsive. But be not
+ afraid. It will all make sense in a bit.
+
+
+
+ - >
hello: hello.o
+ - > > Here, the program "hello" depends on the object file "hello.o".
+ - >
$(FC) $(FFLAGS) -o $@ $^
+ - > > This one compiles the object files into the program.
+ - >
hello.o: hello.f90
+ - > > Here, the object file "hello.o" depends on the source file "hello.f90".
+ - >
$(FC) $(FFLAGS) -c $<
+ - > > This one compiles the source files into the object files.
+ - >
run: ./hello
+ - > > This runs the program if you execute
make run
+ - >
clean: rm -f *.o hello
+ - > > Here, the object files gets removed when running
make clean
+
+
+
+ A quick note. It's very important that whenever something is indented in a makefile, that it's indented with a tab,
+ and not 4 spaces. It needs to be a tab character.
+
+
+ makefile
+
+
+Makefile for hello.f90
+
+FC = gfortran # Fortran compiler
+FFLAGS = -O2 # Compiler flags (optimization level)
+
+hello: hello.o
+ $(FC) $(FFLAGS) -o $@ $^
+
+hello.o: hello.f90
+ $(FC) $(FFLAGS) -c $<
+
+run:
+ ./hello
+
+clean:
+ rm -f *.o hello
+
+
+
+
+ Now simply run the makefile with the following command.
+
+
+
+
+$ make
+gfortran -O2 -c hello.f90
+gfortran -O2 -o hello hello.o
+
+
+
+
+ We have now successfully compiled the program with the help of a makefile. Now simply run the program and we'll
+ see the output.
+
+
+
+
+$ ./hello
+ Hello, World!
+
+
+
+
+ The exact same should happen, if we run the next command instead.
+
+
+
+$ make run
+./hello
+ Hello, World!
+
+
+
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