From 57c1ed2fb35446595ab096dc7618e9c108116f2d Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Fri, 26 Jun 2026 14:49:17 +1000
Subject: [PATCH 01/13] When writing ascii pixmaps, values requiring exponents
 with three or more digits are now truncated to values that can be formatted
 using an exponent of two digits. This prevents invalid values from being
 written to the file as ascii pixmaps are written with values that have
 exponents of two digits. The user is given warnings when the truncation
 happens.

---
 src/write_pixmap.f90 | 30 ++++++++++++++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/src/write_pixmap.f90 b/src/write_pixmap.f90
index 531f1fa1..e00c74b5 100644
--- a/src/write_pixmap.f90
+++ b/src/write_pixmap.f90
@@ -133,11 +133,13 @@ end subroutine writepixmap
 subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,label,filename,time)
  integer, intent(in) :: npixx,npixy
  real,    intent(in), dimension(npixx,npixy) :: datpix
+ real, dimension(npixx,npixy) :: datpixTruncated
  real,    intent(in) :: xmin,ymin,dx,datmin,datmax,time
  character(len=*), intent(in) :: label,filename
  character(len=10) :: stringx,stringy
  character(len=30) :: fmtstring
  integer :: ierr,j
+ integer :: nSmallNegative, nSmallPositive, nLargeNegative, nLargePositive
  integer, parameter :: iunit = 166
 !
 !--write ascii file
@@ -162,18 +164,42 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  write(iunit,"(a,1pe14.6)",          err=66) '# time = ',time
  write(iunit,"(a)",err=66) '# '//trim(adjustl(stringx))//' '//trim(adjustl(stringy))
 
+ datpixTruncated=datpix
+ nSmallNegative = count((datpix > -9.999999E-99) .and. (datpix < 0.0))
+ nSmallPositive = count((datpix < 9.999999E-99) .and. (datpix > 0.0))
+ nLargeNegative = count(datpix < -9.999999E99)
+ nLargePositive = count(datpix > 9.999999E99)
+ where((datpix > -9.999999E-99) .and. (datpix < 0.0)) datpixTruncated = -9.999999E-99
+ where((datpix < 9.999999E-99) .and. (datpix > 0.0)) datpixTruncated = 9.999999E-99
+ where(datpix < -9.999999E99) datpixTruncated = -9.999999E99
+ where(datpix > 9.999999E99) datpixTruncated = 9.999999E99
+
  write(fmtstring,"(a,i6,a)",iostat=ierr) '(',npixx,'(1pe14.6))'
  if (ierr /= 0) then
     do j=1,npixy
-       write(iunit,*,err=66) datpix(1:npixx,j)
+       write(iunit,*,err=66) datpixTruncated(1:npixx,j)
     enddo
  else
     do j=1,npixy
-       write(iunit,fmtstring,err=66) datpix(1:npixx,j)
+       write(iunit,fmtstring,err=66) datpixTruncated(1:npixx,j)
     enddo
  endif
  close(iunit)
  print "(a)",'OK'
+ 
+ if (nSmallNegative > 0) then
+    print "(a,i9,a)","  WARNING: ",nSmallNegative," pixel values are between -9.999999E-99 and 0, setting them to -9.999999E-99"
+ endif
+ if (nSmallPositive > 0) then
+    print "(a,i9,a)","  WARNING: ",nSmallPositive," pixels values are between 0 and 9.999999E-99, setting them to 9.999999E-99"
+ endif
+ if (nLargeNegative > 0) then
+    print "(a,i9,a)","  WARNING: ",nLargeNegative," pixels values are smaller than -9.999999E99, setting them to -9.999999E99"
+ endif
+ if (nLargePositive > 0) then
+    print "(a,i9,a)","  WARNING: ",nLargePositive," pixels values are larger than 9.999999E99, setting them to 9.999999E99"
+ endif
+ 
  return
 
 66 continue

From d2bb5c3c2ccd283f6266577ae08fb9f7a08e39b6 Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Fri, 26 Jun 2026 15:11:35 +1000
Subject: [PATCH 02/13] For writing ascii pixmaps, fixed the smallest/largest
 values that can be represented with a negative exponent of two digits.

---
 src/write_pixmap.f90 | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/write_pixmap.f90 b/src/write_pixmap.f90
index e00c74b5..2f88321c 100644
--- a/src/write_pixmap.f90
+++ b/src/write_pixmap.f90
@@ -165,12 +165,12 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  write(iunit,"(a)",err=66) '# '//trim(adjustl(stringx))//' '//trim(adjustl(stringy))
 
  datpixTruncated=datpix
- nSmallNegative = count((datpix > -9.999999E-99) .and. (datpix < 0.0))
- nSmallPositive = count((datpix < 9.999999E-99) .and. (datpix > 0.0))
+ nSmallNegative = count((datpix > -1.0E-99) .and. (datpix < 0.0))
+ nSmallPositive = count((datpix < 1.0E-99) .and. (datpix > 0.0))
  nLargeNegative = count(datpix < -9.999999E99)
  nLargePositive = count(datpix > 9.999999E99)
- where((datpix > -9.999999E-99) .and. (datpix < 0.0)) datpixTruncated = -9.999999E-99
- where((datpix < 9.999999E-99) .and. (datpix > 0.0)) datpixTruncated = 9.999999E-99
+ where((datpix > -9.999999E-99) .and. (datpix < 0.0)) datpixTruncated = -1.0E-99
+ where((datpix < 9.999999E-99) .and. (datpix > 0.0)) datpixTruncated = 1.0E-99
  where(datpix < -9.999999E99) datpixTruncated = -9.999999E99
  where(datpix > 9.999999E99) datpixTruncated = 9.999999E99
 
@@ -188,10 +188,10 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  print "(a)",'OK'
  
  if (nSmallNegative > 0) then
-    print "(a,i9,a)","  WARNING: ",nSmallNegative," pixel values are between -9.999999E-99 and 0, setting them to -9.999999E-99"
+    print "(a,i9,a)","  WARNING: ",nSmallNegative," pixel values are between -1.0E-99 and 0, setting them to -1.0E-99"
  endif
  if (nSmallPositive > 0) then
-    print "(a,i9,a)","  WARNING: ",nSmallPositive," pixels values are between 0 and 9.999999E-99, setting them to 9.999999E-99"
+    print "(a,i9,a)","  WARNING: ",nSmallPositive," pixels values are between 0 and 1.0E-99, setting them to 1.0E-99"
  endif
  if (nLargeNegative > 0) then
     print "(a,i9,a)","  WARNING: ",nLargeNegative," pixels values are smaller than -9.999999E99, setting them to -9.999999E99"

From a894ddf10c6357742ddbe602874241bfb8a59aaa Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Fri, 26 Jun 2026 15:21:28 +1000
Subject: [PATCH 03/13] For writing ascii pixmaps, fixed some more references
 to incorrect limits for the largest and smallest values that can be
 represented with negative expodents of two digits.

---
 src/write_pixmap.f90 | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/write_pixmap.f90 b/src/write_pixmap.f90
index 2f88321c..4f0c72f1 100644
--- a/src/write_pixmap.f90
+++ b/src/write_pixmap.f90
@@ -169,8 +169,8 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  nSmallPositive = count((datpix < 1.0E-99) .and. (datpix > 0.0))
  nLargeNegative = count(datpix < -9.999999E99)
  nLargePositive = count(datpix > 9.999999E99)
- where((datpix > -9.999999E-99) .and. (datpix < 0.0)) datpixTruncated = -1.0E-99
- where((datpix < 9.999999E-99) .and. (datpix > 0.0)) datpixTruncated = 1.0E-99
+ where((datpix > -1.0E-99) .and. (datpix < 0.0)) datpixTruncated = -1.0E-99
+ where((datpix < 1.0E-99) .and. (datpix > 0.0)) datpixTruncated = 1.0E-99
  where(datpix < -9.999999E99) datpixTruncated = -9.999999E99
  where(datpix > 9.999999E99) datpixTruncated = 9.999999E99
 

From dd473f1a45b8c68949171baa601260dd7c653e07 Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Sat, 27 Jun 2026 01:15:45 +1000
Subject: [PATCH 04/13] In write_pixmap_ascii, ensured that datpixTruncated is
 allocated to the heap instead of the stack.

---
 src/write_pixmap.f90 | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/write_pixmap.f90 b/src/write_pixmap.f90
index 4f0c72f1..08275b16 100644
--- a/src/write_pixmap.f90
+++ b/src/write_pixmap.f90
@@ -133,7 +133,7 @@ end subroutine writepixmap
 subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,label,filename,time)
  integer, intent(in) :: npixx,npixy
  real,    intent(in), dimension(npixx,npixy) :: datpix
- real, dimension(npixx,npixy) :: datpixTruncated
+ real,    dimension(:,:), allocatable :: datpixTruncated
  real,    intent(in) :: xmin,ymin,dx,datmin,datmax,time
  character(len=*), intent(in) :: label,filename
  character(len=10) :: stringx,stringy
@@ -149,6 +149,15 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
     print*,'error opening '//trim(filename)
     return
  endif
+
+ allocate(datpixTruncated(npixx,npixy),stat=ierr)
+ if (ierr /= 0) then
+    print *,"ERROR: Memory allocation of datpixTruncated failed"
+    close(iunit)
+    return
+ endif
+ datpixTruncated=datpix
+ 
  write(*,"(a)",ADVANCE='NO') '> writing pixel map to file '//trim(filename)//' ...'
 
  write(stringx,"(i10)") npixx
@@ -162,9 +171,8 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# x axis: min = ',xmin,' max = ',xmin+(npixx-1)*dx
  write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# y axis: min = ',ymin,' max = ',ymin+(npixy-1)*dx
  write(iunit,"(a,1pe14.6)",          err=66) '# time = ',time
- write(iunit,"(a)",err=66) '# '//trim(adjustl(stringx))//' '//trim(adjustl(stringy))
-
- datpixTruncated=datpix
+ write(iunit,"(a)",err=66) '# '//trim(adjustl(stringx))//' '//trim(adjustl(stringy)) 
+ 
  nSmallNegative = count((datpix > -1.0E-99) .and. (datpix < 0.0))
  nSmallPositive = count((datpix < 1.0E-99) .and. (datpix > 0.0))
  nLargeNegative = count(datpix < -9.999999E99)
@@ -184,6 +192,7 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
        write(iunit,fmtstring,err=66) datpixTruncated(1:npixx,j)
     enddo
  endif
+ deallocate(datpixTruncated)
  close(iunit)
  print "(a)",'OK'
  

From ddaf39a2b4bea4e960ec9e8a5fd8f1b1f78698e4 Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Sun, 28 Jun 2026 01:28:39 +1000
Subject: [PATCH 05/13] Rename write_pixmap.f90 to write_pixmap.F90

---
 src/{write_pixmap.f90 => write_pixmap.F90} | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename src/{write_pixmap.f90 => write_pixmap.F90} (100%)

diff --git a/src/write_pixmap.f90 b/src/write_pixmap.F90
similarity index 100%
rename from src/write_pixmap.f90
rename to src/write_pixmap.F90

From b012c38411e44f8af4f03028d046893ac52a0133 Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Sun, 28 Jun 2026 01:36:24 +1000
Subject: [PATCH 06/13] Changed the extension of write_pixmap to .F90 in
 build/Makefile so it can use the preprocessor.

---
 build/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/build/Makefile b/build/Makefile
index b9aa1a26..05b4f868 100644
--- a/build/Makefile
+++ b/build/Makefile
@@ -473,7 +473,7 @@ SOURCES= $(PLOTLIB) globaldata.f90 physcon.f90 utils_vectors.f90 \
          interpolate3D_proj_geom.f90 \
          interpolate3D_opacity.f90 interpolate_vec.f90 interpolate3D.f90 \
          units.f90 limits.f90 geomutils.f90 dataread_utils.f90 \
-         write_data_gadget.f90 write_data_phantom.f90 write_pfm.f90 write_pixmap.f90 \
+         write_data_gadget.f90 write_data_phantom.f90 write_pfm.f90 write_pixmap.F90 \
          labels_chem.f90 write_griddata.f90 write_sphdata.f90 read_composition.F90 \
          $(SYSTEMFILE) system_utils.f90 \
          cubicsolve.f90 discplot.f90 fparser.f90 parsetext.f90 \

From 8556189e4707f2bf508a7ea09ec3f9c21a18a22f Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Sun, 28 Jun 2026 01:37:19 +1000
Subject: [PATCH 07/13] Changed the extension of write_pixmap to .F90 in
 build/.depends so it can use the preprocessor.

---
 build/.depends | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/build/.depends b/build/.depends
index efe4b84f..ae980be4 100644
--- a/build/.depends
+++ b/build/.depends
@@ -165,5 +165,5 @@ write_data_phantom.o : write_data_phantom.f90
 write_fits.o : write_fits.f90 
 write_griddata.o : write_griddata.F90 asciiutils.o 
 write_pfm.o : write_pfm.f90 
-write_pixmap.o : write_pixmap.f90 asciiutils.o colours.o labels.o write_pfm.o globaldata.o 
+write_pixmap.o : write_pixmap.F90 asciiutils.o colours.o labels.o write_pfm.o globaldata.o 
 write_sphdata.o : write_sphdata.f90 geomutils.o globaldata.o write_data_gadget.o write_data_phantom.o globaldata.o globaldata.o units.o labels.o asciiutils.o 

From 98499fd00be86c65e6646883559b71c3c3a912c7 Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Sun, 28 Jun 2026 02:15:36 +1000
Subject: [PATCH 08/13] For write_pixmap.F90, made it so that the
 write_ascii_pixmap value truncation will only occur when SPLASH is compiled
 in double precision mode as it is unnecessary and creates problems in single
 precision mode. Also added truncation (only in double precision mode) to the
 header datmin and datmax values for the ascii and ppm pixmaps as they use the
 same formatting string as the pixel values.

---
 src/write_pixmap.F90 | 64 ++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 59 insertions(+), 5 deletions(-)

diff --git a/src/write_pixmap.F90 b/src/write_pixmap.F90
index 08275b16..f7a80092 100644
--- a/src/write_pixmap.F90
+++ b/src/write_pixmap.F90
@@ -38,10 +38,53 @@ module write_pixmap
  public :: isinputformat,isoutputformat
  public :: readpixmap
 
+ !The limits for numbers that can be written with the formatting string "1pe14.6"
+#ifdef DP
+ real, parameter, private :: sN = -1.0E-99
+ real, parameter, private :: sP = 1.0E-99
+ real, parameter, private :: lN = -9.999999E99
+ real, parameter, private :: lP = 9.999999E99
+#endif
+
  private
 
 contains
 
+!-----------------------------------------------------------------
+! Truncates the datmin and datmax values for pixmap headers if they are outside the range
+! that can be formatted with the formatting string "1pe14.6"
+!-----------------------------------------------------------------
+subroutine truncateHeaderMinMax(datmin,datmax,datminTruncated,datmaxTruncated)
+ real, intent(in) :: datmin,datmax
+ real, intent(out) :: datminTruncated,datmaxTruncated
+ logical :: datminChanged = .false.
+ logical :: datmaxChanged = .false. 
+ 
+ datminTruncated=datmin
+ datmaxTruncated=datmax
+ 
+#ifdef DP
+ if((datmin > sN) .and. (datmin < 0.0)) then; datminTruncated = sN; datminChanged=.true.; endif
+ if((datmin < sP) .and. (datmin > 0.0)) then; datminTruncated = sP; datminChanged=.true.; endif
+ if(datmin < lN) then; datminTruncated = lN; datminChanged=.true.; endif
+ if(datmin > lP) then; datminTruncated = lP; datminChanged=.true.; endif
+ 
+ if((datmax > sN) .and. (datmax < 0.0)) then; datmaxTruncated = sN; datmaxChanged=.true.; endif
+ if((datmax < sP) .and. (datmax > 0.0)) then; datmaxTruncated = sP; datmaxChanged=.true.; endif
+ if(datmax < lN) then; datmaxTruncated = lN; datmaxChanged=.true.; endif
+ if(datmax > lP) then; datmaxTruncated = lP; datmaxChanged=.true.; endif
+ 
+ if(datminChanged) then
+    print "(a,1pe14.6,a)"," WARNING: pixmap header datmin altered to the value",datminTruncated," as it was either "&
+                          //">9.999999E99, <-9.999999E99, (>1.0E-99 and <0), (<1.0E-99 and >0)"
+ endif
+ if(datmaxChanged) then
+    print "(a,1pe14.6,a)"," WARNING: pixmap header datmax altered to the value",datmaxTruncated," as it was either "&
+                          //">9.999999E99, <-9.999999E99, (>1.0E-99 and <0), (<1.0E-99 and >0)"
+ endif
+#endif
+end subroutine
+
 !-----------------------------------------------------------------
 ! utility to check if an output format selection is valid
 !-----------------------------------------------------------------
@@ -135,6 +178,7 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  real,    intent(in), dimension(npixx,npixy) :: datpix
  real,    dimension(:,:), allocatable :: datpixTruncated
  real,    intent(in) :: xmin,ymin,dx,datmin,datmax,time
+ real :: datminTruncated,datmaxTruncated
  character(len=*), intent(in) :: label,filename
  character(len=10) :: stringx,stringy
  character(len=30) :: fmtstring
@@ -157,7 +201,9 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
     return
  endif
  datpixTruncated=datpix
- 
+
+ call truncateHeaderMinMax(datmin,datmax,datminTruncated,datmaxTruncated)
+
  write(*,"(a)",ADVANCE='NO') '> writing pixel map to file '//trim(filename)//' ...'
 
  write(stringx,"(i10)") npixx
@@ -167,12 +213,13 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  write(iunit,"(a)",err=66) '#   do j=1,'//trim(adjustl(stringy))
  write(iunit,"(a)",err=66) '#      write(*,*) dat(1:'//trim(adjustl(stringx))//',j)'
  write(iunit,"(a)",err=66) '#   enddo'
- write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# '//trim(label)//': min = ',datmin,' max = ',datmax
+ write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# '//trim(label)//': min = ',datminTruncated,' max = ',datmaxTruncated
  write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# x axis: min = ',xmin,' max = ',xmin+(npixx-1)*dx
  write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# y axis: min = ',ymin,' max = ',ymin+(npixy-1)*dx
  write(iunit,"(a,1pe14.6)",          err=66) '# time = ',time
  write(iunit,"(a)",err=66) '# '//trim(adjustl(stringx))//' '//trim(adjustl(stringy)) 
- 
+
+#ifdef DP
  nSmallNegative = count((datpix > -1.0E-99) .and. (datpix < 0.0))
  nSmallPositive = count((datpix < 1.0E-99) .and. (datpix > 0.0))
  nLargeNegative = count(datpix < -9.999999E99)
@@ -181,6 +228,7 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  where((datpix < 1.0E-99) .and. (datpix > 0.0)) datpixTruncated = 1.0E-99
  where(datpix < -9.999999E99) datpixTruncated = -9.999999E99
  where(datpix > 9.999999E99) datpixTruncated = 9.999999E99
+#endif
 
  write(fmtstring,"(a,i6,a)",iostat=ierr) '(',npixx,'(1pe14.6))'
  if (ierr /= 0) then
@@ -195,7 +243,8 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  deallocate(datpixTruncated)
  close(iunit)
  print "(a)",'OK'
- 
+
+#ifdef DP
  if (nSmallNegative > 0) then
     print "(a,i9,a)","  WARNING: ",nSmallNegative," pixel values are between -1.0E-99 and 0, setting them to -1.0E-99"
  endif
@@ -208,6 +257,7 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  if (nLargePositive > 0) then
     print "(a,i9,a)","  WARNING: ",nLargePositive," pixels values are larger than 9.999999E99, setting them to 9.999999E99"
  endif
+#endif
  
  return
 
@@ -227,6 +277,7 @@ subroutine write_pixmap_ppm(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,label,
  real, intent(in), dimension(npixx,npixy) :: datpix
  real, intent(in), dimension(npixx,npixy), optional :: brightness
  real, intent(in) :: xmin,ymin,dx,datmin,datmax
+ real :: datminTruncated,datmaxTruncated
  character(len=*), intent(in) :: label
  integer, intent(in) :: istep
  character(len=120) :: filename
@@ -252,6 +303,9 @@ subroutine write_pixmap_ppm(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,label,
     print*,'error opening ppm file'
     return
  endif
+
+ call truncateHeaderMinMax(datmin,datmax,datminTruncated,datmaxTruncated)
+
  write(*,"(a)",ADVANCE='NO') '> writing pixel map to file '//trim(filename)//' ...'
 !
 !--PPM header
@@ -259,7 +313,7 @@ subroutine write_pixmap_ppm(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,label,
  maxcolour = 255
  write(iunit,"(a)",err=66) 'P3'
  write(iunit,"(a)",err=66) '# '//trim(adjustl(filename))//' created by '//trim(tagline)
- write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# '//trim(label)//': min = ',datmin,' max = ',datmax
+ write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# '//trim(label)//': min = ',datminTruncated,' max = ',datmaxTruncated
  write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# x axis: min = ',xmin,' max = ',xmin+(npixx-1)*dx
  write(iunit,"(a,1pe14.6,a,1pe14.6)",err=66) '# y axis: min = ',ymin,' max = ',ymin+(npixy-1)*dx
  write(iunit,"(i4,1x,i4)",err=66) npixx, npixy

From 6fe2ee7ef8b82d9ab7b5ab8d96093cdd6fc7529c Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Fri, 10 Jul 2026 15:01:59 +1000
Subject: [PATCH 09/13] Made write_pixmap.F90 no longer use the preprocessor
 (and changed its name back to write_pixmap.f90). Also fixed missing
 references to sN,sP,lN and lP in write_pixmap_ascii.

---
 src/{write_pixmap.F90 => write_pixmap.f90} | 46 ++++++++++------------
 1 file changed, 20 insertions(+), 26 deletions(-)
 rename src/{write_pixmap.F90 => write_pixmap.f90} (94%)

diff --git a/src/write_pixmap.F90 b/src/write_pixmap.f90
similarity index 94%
rename from src/write_pixmap.F90
rename to src/write_pixmap.f90
index f7a80092..d138fceb 100644
--- a/src/write_pixmap.F90
+++ b/src/write_pixmap.f90
@@ -39,12 +39,10 @@ module write_pixmap
  public :: readpixmap
 
  !The limits for numbers that can be written with the formatting string "1pe14.6"
-#ifdef DP
- real, parameter, private :: sN = -1.0E-99
- real, parameter, private :: sP = 1.0E-99
- real, parameter, private :: lN = -9.999999E99
- real, parameter, private :: lP = 9.999999E99
-#endif
+ real(kind=8), parameter, private :: sN = -1.0E-99
+ real(kind=8), parameter, private :: sP = 1.0E-99
+ real(kind=8), parameter, private :: lN = -9.999999E99
+ real(kind=8), parameter, private :: lP = 9.999999E99
 
  private
 
@@ -55,15 +53,14 @@ module write_pixmap
 ! that can be formatted with the formatting string "1pe14.6"
 !-----------------------------------------------------------------
 subroutine truncateHeaderMinMax(datmin,datmax,datminTruncated,datmaxTruncated)
- real, intent(in) :: datmin,datmax
- real, intent(out) :: datminTruncated,datmaxTruncated
+ real(kind=8), intent(in) :: datmin,datmax
+ real(kind=8), intent(out) :: datminTruncated,datmaxTruncated
  logical :: datminChanged = .false.
  logical :: datmaxChanged = .false. 
  
  datminTruncated=datmin
  datmaxTruncated=datmax
  
-#ifdef DP
  if((datmin > sN) .and. (datmin < 0.0)) then; datminTruncated = sN; datminChanged=.true.; endif
  if((datmin < sP) .and. (datmin > 0.0)) then; datminTruncated = sP; datminChanged=.true.; endif
  if(datmin < lN) then; datminTruncated = lN; datminChanged=.true.; endif
@@ -82,7 +79,6 @@ subroutine truncateHeaderMinMax(datmin,datmax,datminTruncated,datmaxTruncated)
     print "(a,1pe14.6,a)"," WARNING: pixmap header datmax altered to the value",datmaxTruncated," as it was either "&
                           //">9.999999E99, <-9.999999E99, (>1.0E-99 and <0), (<1.0E-99 and >0)"
  endif
-#endif
 end subroutine
 
 !-----------------------------------------------------------------
@@ -176,9 +172,9 @@ end subroutine writepixmap
 subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,label,filename,time)
  integer, intent(in) :: npixx,npixy
  real,    intent(in), dimension(npixx,npixy) :: datpix
- real,    dimension(:,:), allocatable :: datpixTruncated
+ real(kind=8),    dimension(:,:), allocatable :: datpixTruncated
  real,    intent(in) :: xmin,ymin,dx,datmin,datmax,time
- real :: datminTruncated,datmaxTruncated
+ real(kind=8) :: datminTruncated,datmaxTruncated
  character(len=*), intent(in) :: label,filename
  character(len=10) :: stringx,stringy
  character(len=30) :: fmtstring
@@ -200,9 +196,9 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
     close(iunit)
     return
  endif
- datpixTruncated=datpix
+ datpixTruncated=real(datpix,kind=8)
 
- call truncateHeaderMinMax(datmin,datmax,datminTruncated,datmaxTruncated)
+ call truncateHeaderMinMax(real(datmin,kind=8),real(datmax,kind=8),datminTruncated,datmaxTruncated)
 
  write(*,"(a)",ADVANCE='NO') '> writing pixel map to file '//trim(filename)//' ...'
 
@@ -219,16 +215,14 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  write(iunit,"(a,1pe14.6)",          err=66) '# time = ',time
  write(iunit,"(a)",err=66) '# '//trim(adjustl(stringx))//' '//trim(adjustl(stringy)) 
 
-#ifdef DP
- nSmallNegative = count((datpix > -1.0E-99) .and. (datpix < 0.0))
- nSmallPositive = count((datpix < 1.0E-99) .and. (datpix > 0.0))
- nLargeNegative = count(datpix < -9.999999E99)
- nLargePositive = count(datpix > 9.999999E99)
- where((datpix > -1.0E-99) .and. (datpix < 0.0)) datpixTruncated = -1.0E-99
- where((datpix < 1.0E-99) .and. (datpix > 0.0)) datpixTruncated = 1.0E-99
- where(datpix < -9.999999E99) datpixTruncated = -9.999999E99
- where(datpix > 9.999999E99) datpixTruncated = 9.999999E99
-#endif
+ nSmallNegative = count((datpixTruncated > sN) .and. (datpixTruncated < 0.0))
+ nSmallPositive = count((datpixTruncated < sP) .and. (datpixTruncated > 0.0))
+ nLargeNegative = count(datpixTruncated < lN)
+ nLargePositive = count(datpixTruncated > lP)
+ where((datpixTruncated > sN) .and. (datpixTruncated < 0.0)) datpixTruncated = sN
+ where((datpixTruncated < sP) .and. (datpixTruncated > 0.0)) datpixTruncated = sP
+ where(datpixTruncated < lN) datpixTruncated = lN
+ where(datpixTruncated > lP) datpixTruncated = lP
 
  write(fmtstring,"(a,i6,a)",iostat=ierr) '(',npixx,'(1pe14.6))'
  if (ierr /= 0) then
@@ -277,7 +271,7 @@ subroutine write_pixmap_ppm(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,label,
  real, intent(in), dimension(npixx,npixy) :: datpix
  real, intent(in), dimension(npixx,npixy), optional :: brightness
  real, intent(in) :: xmin,ymin,dx,datmin,datmax
- real :: datminTruncated,datmaxTruncated
+ real(kind=8) :: datminTruncated,datmaxTruncated
  character(len=*), intent(in) :: label
  integer, intent(in) :: istep
  character(len=120) :: filename
@@ -304,7 +298,7 @@ subroutine write_pixmap_ppm(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,label,
     return
  endif
 
- call truncateHeaderMinMax(datmin,datmax,datminTruncated,datmaxTruncated)
+ call truncateHeaderMinMax(real(datmin,kind=8),real(datmax,kind=8),datminTruncated,datmaxTruncated)
 
  write(*,"(a)",ADVANCE='NO') '> writing pixel map to file '//trim(filename)//' ...'
 !

From 0a3ef8d5759ff751289330ad0b4668d7c4056b2b Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Fri, 10 Jul 2026 15:03:43 +1000
Subject: [PATCH 10/13] In Makefile, changed extension of write_pixmap back to
 .f90.

---
 build/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/build/Makefile b/build/Makefile
index 05b4f868..b9aa1a26 100644
--- a/build/Makefile
+++ b/build/Makefile
@@ -473,7 +473,7 @@ SOURCES= $(PLOTLIB) globaldata.f90 physcon.f90 utils_vectors.f90 \
          interpolate3D_proj_geom.f90 \
          interpolate3D_opacity.f90 interpolate_vec.f90 interpolate3D.f90 \
          units.f90 limits.f90 geomutils.f90 dataread_utils.f90 \
-         write_data_gadget.f90 write_data_phantom.f90 write_pfm.f90 write_pixmap.F90 \
+         write_data_gadget.f90 write_data_phantom.f90 write_pfm.f90 write_pixmap.f90 \
          labels_chem.f90 write_griddata.f90 write_sphdata.f90 read_composition.F90 \
          $(SYSTEMFILE) system_utils.f90 \
          cubicsolve.f90 discplot.f90 fparser.f90 parsetext.f90 \

From f0effd8af1c6f1a05dbf0d27b348171713a08d90 Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Fri, 10 Jul 2026 15:05:17 +1000
Subject: [PATCH 11/13] In .depends, changed extension of write_pixmap back to
 .f90.

---
 build/.depends | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/build/.depends b/build/.depends
index ae980be4..efe4b84f 100644
--- a/build/.depends
+++ b/build/.depends
@@ -165,5 +165,5 @@ write_data_phantom.o : write_data_phantom.f90
 write_fits.o : write_fits.f90 
 write_griddata.o : write_griddata.F90 asciiutils.o 
 write_pfm.o : write_pfm.f90 
-write_pixmap.o : write_pixmap.F90 asciiutils.o colours.o labels.o write_pfm.o globaldata.o 
+write_pixmap.o : write_pixmap.f90 asciiutils.o colours.o labels.o write_pfm.o globaldata.o 
 write_sphdata.o : write_sphdata.f90 geomutils.o globaldata.o write_data_gadget.o write_data_phantom.o globaldata.o globaldata.o units.o labels.o asciiutils.o 

From a70b5f931a76c387d9c25879b8816fddadb1ddd3 Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Fri, 10 Jul 2026 15:11:39 +1000
Subject: [PATCH 12/13] Fixed an #ifdef and #endif that I accidentally left in
 write_pixmap.f90.

---
 src/write_pixmap.f90 | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/write_pixmap.f90 b/src/write_pixmap.f90
index d138fceb..b9c49131 100644
--- a/src/write_pixmap.f90
+++ b/src/write_pixmap.f90
@@ -238,7 +238,6 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  close(iunit)
  print "(a)",'OK'
 
-#ifdef DP
  if (nSmallNegative > 0) then
     print "(a,i9,a)","  WARNING: ",nSmallNegative," pixel values are between -1.0E-99 and 0, setting them to -1.0E-99"
  endif
@@ -251,7 +250,6 @@ subroutine write_pixmap_ascii(datpix,npixx,npixy,xmin,ymin,dx,datmin,datmax,labe
  if (nLargePositive > 0) then
     print "(a,i9,a)","  WARNING: ",nLargePositive," pixels values are larger than 9.999999E99, setting them to 9.999999E99"
  endif
-#endif
  
  return
 

From 97d21390b5a61cca645f964aabf1fc076de79b3d Mon Sep 17 00:00:00 2001
From: Stephen Neilson <36410751+s-neilson@users.noreply.github.com>
Date: Fri, 10 Jul 2026 15:24:03 +1000
Subject: [PATCH 13/13] In write_pixmap.f90, changed the values of sN,sP,lN and
 lP to double precision literals.

---
 src/write_pixmap.f90 | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/write_pixmap.f90 b/src/write_pixmap.f90
index b9c49131..fd9d8588 100644
--- a/src/write_pixmap.f90
+++ b/src/write_pixmap.f90
@@ -39,10 +39,10 @@ module write_pixmap
  public :: readpixmap
 
  !The limits for numbers that can be written with the formatting string "1pe14.6"
- real(kind=8), parameter, private :: sN = -1.0E-99
- real(kind=8), parameter, private :: sP = 1.0E-99
- real(kind=8), parameter, private :: lN = -9.999999E99
- real(kind=8), parameter, private :: lP = 9.999999E99
+ real(kind=8), parameter, private :: sN = -1.0d-99
+ real(kind=8), parameter, private :: sP = 1.0d-99
+ real(kind=8), parameter, private :: lN = -9.999999d99
+ real(kind=8), parameter, private :: lP = 9.999999d99
 
  private