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FC=gfortran
FCFLAGS=-Wall -O2 -fopenmp
.phony: all clean
all: abcd
abcd: abcd.F90
$(FC) $(FCFLAGS) -o $@ $<
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ivan-pi / test_mmap.f90
Last active January 16, 2023 16:23
Virtual memory array in Fortran based on POSIX system headers
! test_mmap.f90
!
! compile with:
! gfortran -Wall -O2 -o test_mmap test_mmap.f90
!
! inspired by the work:
! Rojc, B., & Depolli, M. (2021). A Resizable C++ Container using Virtual Memory. In ICSOFT (pp. 481-488).
! https://www.scitepress.org/Papers/2021/105571/105571.pdf
!
! so far I've only tested this on MacOS
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ivan-pi / linspace.f90
Created December 19, 2019 18:54
Linspace in Fortran
module linspace_mod
use iso_fortran_env, only: dp => real64
implicit none
contains
!>
! Return evenly spaced numbers over a specified interval.
!
! Returns `num` evenly spaced samples, calculated over the interval `[start, stop]`.
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ivan-pi / fortran_links.md
Created January 20, 2022 13:52
Resources on Fortran
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ivan-pi / interop.f90
Created September 27, 2022 15:41
Example of using C descriptors to call a routine implemented in Fortran
module interop
use, intrinsic :: iso_c_binding, only: c_int
implicit none
contains
subroutine fillint(arr) bind(c)
integer(c_int), intent(inout) :: arr(:)
integer :: i
arr = [(i**2,i=1,size(arr))]
end subroutine
end module
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ivan-pi / ghiau.txt
Created April 18, 2019 14:31
Lid-driven cavity flow benchmark u-velocity values from Ghia, U. K. N. G., Ghia, K. N., & Shin, C. T. (1982), Journal of computational physics, 48(3), 387-411.
# Ghia, U. K. N. G., Ghia, K. N., & Shin, C. T. (1982).
# High-Re solutions for incompressible flow using the Navier-Stokes equations and a multigrid method.
# Journal of computational physics, 48(3), 387-411.
#
# TABLE I
# Results for $u$-velocity along Vertical Line through Geometric Center of Cavity
#--------------------------------------------------------------------
# Re
# -------------------------------------------------------------
# y 100 400 1000 3200 5000 7500 10000
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ivan-pi / bisect.cxx
Last active August 25, 2022 07:42
Passing a C Function Callback to the Boost Math Toolkit Root Finding Library
// compile with g++ -o bisect.cxx poly.o -I<path/to/boost>
#include <cmath>
#include <iostream>
#include <boost/math/tools/roots.hpp>
// Functor providing termination condition
// Determines convergence in x based on if the relative or absolute tolerance are satisfied
template<class T>
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ivan-pi / pcg32.f90
Last active July 12, 2022 10:21
Attempt of porting the PCG random number generator by Melissa O'Neill to Fortran. The code is not tested. Signed integers are used for the state.
!
! PCG Random Number Generation for Fortran
! Ported from the minimal C version by Melissa O'Neill
!
! Copyright 2020 Ivan Pribec <ivan.pribec@gmail.com>
!
!
! Copyright 2014 Melissa O'Neill <oneill@pcg-random.org>
!
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ivan-pi / lapack_interface.f90
Last active March 22, 2022 21:36
Example of LU factorization using Fortran parameterized derived types
module lapack
implicit none
interface
subroutine sgetrf(m,n,a,lda,ipiv,info)
integer, intent(in) :: m, n, lda
real, intent(inout) :: a(lda,*)
integer, intent(out) :: ipiv(*)
integer, intent(out) :: info
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ivan-pi / fortran_namelist.xml
Created December 27, 2021 11:20
Fortran namelist configuration file for Notepad++
<NotepadPlus>
<UserLang name="Fortran Namelist" ext="nml" udlVersion="2.1">
<Settings>
<Global caseIgnored="yes" allowFoldOfComments="no" foldCompact="no" forcePureLC="0" decimalSeparator="0" />
<Prefix Keywords1="no" Keywords2="no" Keywords3="no" Keywords4="no" Keywords5="no" Keywords6="no" Keywords7="no" Keywords8="no" />
</Settings>
<KeywordLists>
<Keywords name="Comments">00! 01 02 03 04</Keywords>
<Keywords name="Numbers, prefix1">.</Keywords>
<Keywords name="Numbers, prefix2"></Keywords>