From bd3e494732cec25f9d1bed99a16ef6ea53466b23 Mon Sep 17 00:00:00 2001
From: Guilhem Lavaux <guilhem.lavaux@gmail.com>
Date: Tue, 23 Oct 2012 10:30:13 -0400
Subject: [PATCH] Opportunity to change the unit of gadget file

---
 mytools/generateMock.cpp | 12 +++++++++++-
 mytools/generateMock.ggo |  3 ++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/mytools/generateMock.cpp b/mytools/generateMock.cpp
index c1e686b..60675ac 100644
--- a/mytools/generateMock.cpp
+++ b/mytools/generateMock.cpp
@@ -18,6 +18,8 @@ using namespace CosmoTool;
 
 #define LIGHT_SPEED 299792.458
 
+static double gadgetUnit=1e-3;
+
 SimuData *doLoadRamses(const char *basename, int baseid, int velAxis, bool goRedshift)
 {
   SimuData *d, *outd;
@@ -65,7 +67,13 @@ SimuData *doLoadRamses(const char *basename, int baseid, int velAxis, bool goRed
 
 SimuData *myLoadGadget(const char *fname, int id, int flags)
 {
-  return loadGadgetMulti(fname, id, flags);
+  SimuData *sim = loadGadgetMulti(fname, id, flags);
+  sim->BoxSize *= gadgetUnit;
+  for (int j = 0; j < 3; j++)
+    for (long i = 0; i < sim->NumPart; i++)
+      sim->Pos[j][i] *= gadgetUnit;
+
+  return sim;
 }
 
 SimuData *doLoadSimulation(const char *gadgetname, int velAxis, bool goRedshift, SimuData *(*loadFunction)(const char *fname, int id, int flags))
@@ -490,6 +498,8 @@ int main(int argc, char **argv)
   
   generateMock_conf_print_version();
 
+  gadgetUnit=args_info.gadgetUnit_arg;
+
   if (args_info.ramsesBase_given || args_info.ramsesId_given)
     {
       if (args_info.ramsesBase_given && args_info.ramsesId_given)  
diff --git a/mytools/generateMock.ggo b/mytools/generateMock.ggo
index e530df9..c048e20 100644
--- a/mytools/generateMock.ggo
+++ b/mytools/generateMock.ggo
@@ -29,4 +29,5 @@ option "cosmo"	- "Apply cosmological redshift" flag on
 
 option "subsample" - "Subsample the input simulation by the specified amount" double optional
 
-option "inputParameter" - "Input geometry (optional, warning!)" string optional
\ No newline at end of file
+option "inputParameter" - "Input geometry (optional, warning!)" string optional
+option "gadgetUnit" - "Unit of length in gadget file in Mpc/h" double optional default="0.001"